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Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from Atmospheric Aerosols in a Remote Tropical Region in East Asia

Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... The Arctic Oscillation (AO) accounts for a large fraction of recent decadal climate trends in Northern Hemisphere (NH) high latitudes. In East Asia, an elevated AO index (AOI) was associated with warmer temperatures in middle- to high-latitude regions, colder temperatures over low-latitude regions, and elevated ozone intrusion from the stratosphere. Elevated beryllium-7 ( Be) is produced in the stratosphere. Few studies have discussed the relationship between Be and the AO. Here, we identify the AO signature in Be and lead (Pb)-210 observed at a tropical ambient monitoring site in Nanning (22.8°N, 108.5°E) during the 7 210 December 2014–December 2017 period. Our results show that the Be and Pb concentrations are positively and significantly 7 210 correlated with the AOI (P < 0.01). These results show that elevated Be and Pb are associated with an increase in the AOI, reflecting air masses originating from NH high latitudes and vertically from the high-latitude upper troposphere and lower stratosphere regions to tropical latitudes in East Asia. These results have been verified with ozonesonde data without seasonality and with two meteorological data sets. Our results are also confirmed by observational data over the Pacific regions. We conclude that the AO exerts impacts over the tropical regions in East Asia, and Be can be used as a tracer to track the impacts of the AO. . . . . Keywords Beryllium-7 Lead-210 Arctic oscillation Atmospheric aerosols Nanning 1 Introduction winter and spring (Thompson and Wallace 2000;Hurrell et al. 2003). Its variability is commonly manifested by a sea- The Arctic Oscillation (AO) is the primary reason for the level pressure (SLP) difference between stations in the Azores interannual variability in the troposphere and lower strato- (Portugal) and Iceland (Thompson and Wallace 1998; Cutlip sphere. The AO affects the extratropical surface climate vari- 2000; Thompson and Wallace 2000; Thompson and Wallace ability in the Northern Hemisphere (NH), especially during 2001; Thompson and Lorenz 2004). The AO initially ema- nates from the stratosphere and ultimately alters surface weather, subsequently affecting the temperature and precipi- Responsible Editor: Jong-Seong Kug. tation in most NH areas. Hence, the AO is closely related to the frequency and intensity of extreme weather events * Kuo-Ying Wang (Thompson and Wallace 1998; Thompson and Wallace kuoying@mail.atm.ncu.edu.tw 2000; Thompson and Wallace 2001; Black 2002;Thompson and Lorenz 2004). School of Marine Sciences, Guangxi University, Nanning 530004, China In particular, the AO accounts for a large fraction of recent decadal climate trends in high northern latitudes (Hurrell College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China 1995;Thompson et al. 2000). Thompson et al. (2001) found 3 that in recent decades, the continuous high trend of the North Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Nanning 530004, China Atlantic Oscillation (NAO, which can be viewed as an AO subset (Jevrejeva and Moore 2001)) is an important reason for Radiation-Environment Management and Monitoring Station of Guangxi Zhuang Autonomous Region, Nanning 530222, China winter warming in the NH. In East Asia, as the winter AO index increases from low to high, the temperatures in the Department of Atmospheric Sciences, National Central University, Chung-Li District Taoyuan City, Taiwan middle- and high-latitude regions of the Asian continent Korean Meteorological Society X. Chen et al. become warmer, the low-latitude regions become colder, and this can produce radium, (Ra)-226, and radon, (Rn)-222, vice versa (Wu and Wang 2002;Gongetal. 2001; Jeong and which are precursors of lead, (Pb)-210 ( Pb). Due to the 222 210 Ho 2005;Chen etal. 2013). continental origin of Rn, Pb is considered a tracer of Beryllium-7 ( Be) is a sensitive indicator of stratospheric air masses with continental origins (Balkanski et al. 1983; air intrusion into the troposphere and this radionuclide is clas- Turekian et al. 1983;Baskaran 2011). Rn emanates sically applied in the stratosphere-troposphere exchange primarily from rocks and minerals in the crust. (STE) (Dibb et al. 1992; Bonasonietal. 1999, 2000a, b; Therefore, the spatial variability of Pb is strongly de- Cristofanelli et al. 2007, 2006, 2009). In contrast, Pb has pendent on the geographical types of terrestrial surfaces, been used as a continental tracer of air masses and long-range and the Rn flux from the ocean is negligible (San transport of chemical constituents (derived from continental Miguel et al. 2019). 210 210 sources) (Balkanski et al. 1983;Turekianetal. 1983; Po and Pb nuclides are concentrated in the air Baskaran 2011). The cosmogenic radionuclide Be (its half- over inland cities and industrial areas because of artificial life is 53.3 days) is produced by high-energy spallation inter- sources, such as industrial mining, automobile exhaust actions between galactic cosmic-ray (GCR)-produced neu- and construction dust (burning of coal, use of phosphate trons and protons (secondary particles) and atmospheric nu- fertilizers, car exhaust, and fires) (Jaworowski et al. 1980; clei (primarily nitrogen, oxygen and argon) (Lal and Peters Hotzl and Winkler 1987;Lozanoetal. 2013). Once 7 210 210 1967;UNSCEAR 2000; Usoskin and Kovaltsov 2008; formed in the air, Be, Pb, and Po are rapidly com- Papastefanou 2009;see Fig. S1). bined with submicron-sized aerosol particles (Maenhaut Increased ozone over much of Asia results from the posi- et al. 1979; Bondietti et al. 1987; Papastefanou 2009). tive phase of the AO combined with changes in the Hence, their concentrations in air are similar to those of stratosphere-troposphere exchange (STE; Holton et al. 1995; aerosol particles and depend on atmospheric transport and Wang et al. 2002; Wang and Kau 2015) that are responsible wet and dry removal (Papastefanou and Ioannidou 1995; for the correlation pattern between ozone and AO at 800 hPa Baskaran 2011). (Lamarque and Hess 2004). This study shows that the tropo- Because of the different sources of the two radionu- 7 210 spheric ozone concentration over Asia is affected by the in- clides, simultaneous measurements of Be and Pb and trusion of stratospheric ozone. Similar to air containing ele- their ratios can be implemented to identify the origin of vated ozone levels in the stratosphere, an elevated Be level air masses (Graustein and Turekian 1996;Bonasonietal. occurs in the stratosphere. Hence, Be is a stratospheric tracer 2000a, b; Zheng et al. 2005) and to study the vertical that can be directly or indirectly influenced by the AO. motion of air masses and convective activity in the tropo- Similar to Be, ozone from the stratosphere is consid- sphere (Brost et al. 1991;Kochetal. 1996; Lee et al. ered an indicator of the Arctic Oscillation (Thompson and 2004; Tositti et al. 2004; Lee et al. 2007). Moreover, Wallace 2000; Lamarque and Hess 2004;Dibbetal. temporal and spatial variations in this ratio reflect both 1992). However, few studies have discussed the relation- vertical and horizontal transport in the atmosphere ship between Be and the Arctic Oscillation. It is worth (Koch et al. 1996;Baskaran 2011). Due to their half- 7 210 7 discussing whether Be can be used as a tracer to track the lives (22.3 years for Pb and53.2daysfor Be), both Arctic Oscillation and whether the signal of the Arctic natural radionuclides can persist long enough for long- Oscillation can be discovered through aerosol data in the range transport in the atmosphere (Zhang et al. 2015; tropics to study the mechanism of climate teleconnection. Grossi et al. 2016;San Migueletal. 2019). Production of Be is the highest in the stratosphere (75%), In this paper, we report a three-year (2014/10–2017/12) 7 210 while the remaining part (25%) is produced in the upper study conducted on the abundance of Be, Pb, and troposphere (Johnson and Viezee 1981; UNSCEAR 2000; Po in the surface air over tropical urban site Nanning, Usoskin and Kovaltsov 2008). Be production increases China (22.8°N, 108.5°E). In addition, the interrelationship with altitude and geomagnetic latitude and is also associ- among these nuclides and a suite of related environmental ated with the 11-year solar cycle that modulates cosmic- factors, such as the AO, precipitation, cosmic rays, and ray penetration through the Earth’s magnetic field (Lal earthquakes, are also investigated. This paper adopts the and Peters 1967; Bhandari and Lal 1970;Dibbetal. Hybrid Single-Particle Lagrangian Integrated Trajectory 1992;UNSCEAR 2000; Usoskin and Kovaltsov 2008). (HYSPLIT) model to calculate the origins of air masses The polar stratosphere experiences the highest production reaching the Nanning sampling site, compares the rate, and the tropical lower troposphere exhibits the low- Nanning results to Environmental Measurements est production rate (Feely et al. 1989). Laboratory (EML) observations, and applies a regression Pb (with a half-life of 22.3 years) and its progeny model to study the correlations among the variables of polonium, (Po)-210, originate from the naturally occur- AOI, precipitation, air mass origin (latitude, longitude, 7 210 ring radionuclide uranium, (U)-238, in the environment; and altitude), Be, and Pb. Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... Table 1 Abundances of Be, 210 210 7 3 210 210 Code Start time* Finish time* Po(mBq/ Pb(mBq/ Be (mBq/m ) Pb, and Po in ambient 3 3 m ) m ) aerosols over Nanning 1 09.10.2014, / 10.10.2014, / 0.55 3.92 12.7 2 04.11.2014, / 05.11.2014, / 0.52 1.62 9.09 3 08.12.2014,09:19 09.12.2014,10:00 0.3 3.63 10.3 4 05.01.2015,10:38 06.01.2015,10:39 0.48 0.71 6.08 5 02.02.2015,09:28 03.02.20150,9:40 0.34 3.3 1.1 6 04.03.2015,08:25 05.03.2015,08:35 0.84 1.9 3.36 7 13.04.2015,10:30 14.04.2015,10:30 0.9 2.13 9.37 8 04.05.2015,09:10 05.05.2015,09:48 0.76 0.83 1.48 9 16.06.2015,08:58 17.06.2015,09:05 0.8 0.88 1.03 10 22.07.2015,09:04 23.07.2015,10:18 0.59 0.36 0.9 11 10.08.2015,09:45 11.08.2015,09:50 0.74 0.77 1.97 12 23.09.2015,09:27 24.09.2015,10:24 0.52 1.58 2.61 13 19.10.2015,10:08 20.10.2015,10:23 0.69 2.43 7.56 14 02.11.2015,16:07 03.11.2015,16:46 0.61 2.63 4.91 15 16.12.2015,10:51 17.12.2015,14:57 0.72 2.79 7.83 16 19.01.2016,10:39 20.01.2016,11:19 1.19 3.12 8.41 17 16.02.2016,10:32 17.02.2016,10:45 0.43 1.26 8.5 18 01.03.2016,10:05 02.03.2016,16:07 1.16 1.67 8.98 19 06.04.2016,14:50 07.04.2016,15:07 0.34 0.92 4.66 20 03.05.2016,10:13 04.05.2016,10:35 0.24 2.47 3.47 21 27.06.2016,09:50 28.06.2016,10:11 0.19 0.23 0.84 22 18.07.2016,08:40 19.07.2016,08:52 0.31 0.34 2.47 23 08.08.2016,11:35 09.08.2016,11:12 0.8 0.83 1.1 24 18.09.2016,16:00 19.09.2016,16:20 0.67 1.28 3.55 25 09.10.2016,09:01 10.10.2016,08:56 0.87 1.71 3.52 26 14.11.2016,11:10 15.11.2016,11:35 0.18 0.61 0.78 27 07.12.2016,10:42 08.12.2016,10:32 1 1.62 9.66 28 03.01.2017,11:50 04.01.2017,12:05 0.869 2.309 5.76 29 13.02.2017,10:38 13.02.2017,10:38 0.515 1.412 6.55 30 02.03.2017,15:52 03.03.2017,15:08 1.679 2.622 7.69 31 17.04.2017,10:56 18.04.2017,11:24 0.393 0.854 1.21 32 03.05.2017,17:15 04.05.2017,17:22 0.223 1.129 2.14 33 20.06.2017,11:00 21.06.2017,09:45 0.625 0.669 0.484 34 20.07.2017,09:45 21.07.2017,09:15 0.227 0.238 0.765 35 07.08.2017,11:25 08.08.2017,11:16 0.517 0.372 0.743 36 29.09.2017,16:35 30.09.2017,17:15 0.235 0.265 0.387 37 30.10.2017,09:00 31.10.2017,17:05 0.905 1.314 0.781 38 17.11.2017,16:10 19.11.2017,11:50 0.172 0.298 0.649 39 09.12.2017,20:12 10.12.2017,19:33 0.538 2.054 0.646 *The local time of Nanning is given in the following format: DDMMYY, HH:MM (day, month, year, hour, minute; 08.12.2014 is read as 8 December 2014) In this work, we show that air movement in the polar strato- mechanism driving air movement variations in the sphere affects the tropical troposphere based on observations stratosphere-troposphere coupling system. We adopt Be as of radioactive materials near the ground in the tropics. These a tracer for the stratosphere and Pb as a tracer for the tro- chemical observations further strengthen the dynamic aspects posphere. With this framework, this work addresses the fol- of stratosphere-troposphere coupling processes (Hoskins et al. lowing issues. (1) A significant correlation has been observed 1985). In this paper, we consider the AO as the main between Be and AOI, proving that the impact of the AO from Korean Meteorological Society X. Chen et al. the NH polar stratosphere can be observed near the surface of system containing a model BE3830 detector (CANBERRA) the tropical troposphere. (2) The good linear correlations be- with a crystal size of Φ 80 mm × 30 mm. The counting error 7 210 tween Be and Pb indicate that the stratosphere and tropo- for radioactivity measurements was approximately 10% at the sphere are coupled. 1 sigma level (Lee et al. 2004). The linear energy scale of the analyzer was calibrated with photon peaks from a Co-60 source (1332 keV) with the full width at half maximum (FWHM) of energy no higher than 1.80 keV and with a 2 Data and Methods 50.9% relative efficiency. The measurement time was longer than 86,400 s, and the minimum detection limits for Be, 2.1 Observational Data 210 210 3 Pb, and Po were 0.017–0.022 mBq/m ,0.01–0.03 3 3 mBq/m and 0.001–0.005 mBq/m , respectively. The uncer- 2.1.1 Site Description 210 7 tainties of Pb and Be activities were controlled to below 5%, and the uncertainties of Po were approximately 13%. The sampling site is an automatic environmental station in 7 210 In this paper, the Be and Pb activities were determined Nanning city, China (22.8°N, 108.5°E). Nanning has a humid with γ rays of 477.6 keV (Pγ = 10.43%) and 46.5 keV (Pγ = subtropical monsoon climate with an average temperature of 4.05%), respectively. The detection efficiency was obtained 21.7 °C and abundant rainfall (Deng et al. 2018). The average with laboratory source calibration software (LabSOCS). annual rainfall is 1298 mm, and Nanning has a humid summer LabSOCS was considered reliable for gamma ray detector and a slightly dry winter with distinctive dry and wet seasons efficiency calibrations, and the deviation of detection efficien- (which result from the impact of the Asian monsoon). cy calculated by this method was less than 10% (Bronson 2003;Liand Geng, 2010;Done et al. 2016). The γ energy 2.1.2 Sample Collection spectrum data were analyzed with Genie-2000 spectrum anal- ysis software to obtain the activities and uncertainties of Pb Aerosol samples are collected with a PM-800 large-flow aero- 7 3 and Be in the aerosol samples (mBq/m ) (Rastogi and Sarin sol sampler with a mounted HB1 polypropylene fiber filter 2008; Baskaran and Shaw 2001;Leppänenetal. 2010; membrane and an electric tablet press (Fig. 1). The collection Dueñas et al. 2011;Duet al. 2020). efficiency of the HB1 filter membrane for 0.5 μm aerosol After gamma spectrometry analysis, each sample was particles is approximately 99%. The operational flow of the 3 spiked with Po as a tracer, and the polonium in the sample sampler is set to 600 m /h to ensure that the standard- 3 was then dissolved with concentrated nitric acid. The residue condition volume of sampling is not smaller than 10,000 m . was dissolved/leached with hydrochloric acid, and ascorbic After sampling, the volume of air and the start and end times acid was added thereafter. In the hydrochloric acid system, are recorded. The sampling frequency is one sample over ap- polonium was self-plated onto a silver disc and determined proximately 24 h every month from October 2014 to with an alpha spectrometry (Canberra, 7200–4 PIPS) instru- December 2017. The total number of samples is 39. Each ment connected to an Alpha Analyst to calculate the activity aerosol sample is compressed into a cylinder with a diameter of Po (Carvalho 1995; Huh and Su 1999; Baskaran and of 70 mm and a length of 10 mm (Bourcier et al. 2011; Zhang Shaw 2001; Daish et al. 2005;Matthews et al. 2007). et al. 2015). 2.1.3 Sample Analysis 2.2 The HYSPLIT Model After encapsulation, the radioactivity was measured with a In this work, we apply the National Oceanic and Atmospheric high-purity germanium gamma (HPGe-γ) spectrometer Administration (NOAA) HYSPLIT model (Stein et al. 2016) Fig. 1 a The aerosol collector is installed in the integrated automatic monitoring station, and the sampling port is approximately 2 m from ground level; b theinsideofthe aerosol collector where the filter membrane is placed; c the filter membrane, where the black areas are aerosols Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... to produce back trajectories in the filtering sampling periods To rank the effects of the above parameters on the surface- with a duration of 168 h (7 days). Back trajectories are calcu- observed X, we apply a linear regression model to compute the lated every six hours over a specific sampling period. The statistical correlations between both the observed X and vari- source site is located in Nanning (latitude: 22.8°N; longitude: ables and among the variables (Wang and Chau 2013). The 108.5°E), and the height is 100 m above ground level because correlations between two variables are measured by the cal- the air below 100 m can be regarded as a uniform mixing culated correlation coefficient R. The statistical significance of layer. The vertical motion calculation method relies on a ver- a correlation is tested by computing Student’s t test probability tical velocity model, for which we use the meteorology over P(Press et al. 1992). the sampling period from the National Centers for Environmental Prediction (NCEP) GDAS0p5 (Global Data 2.4 The US EML Global Air Sampling Data Assimilation System 0.5 degrees longitude-latitude). Since the number of samples is 39 and the duration of each sampling The US EML has a network of air sampling sites that measure 7 210 period is longer than 20 h, there are a total of 144 back Be, Pb, and other nuclides on a global scale (Larsen et al. trajectories. 1995). The global coverage of EML surface sites is excellent for comparing and testing the results obtained from the analysis of local measurements performed in Nanning. It is important to test 2.3 Linear Regression Search whether the results obtained from Nanning are specific only to Nanning or whether they are general features on a global scale. In For a surface-observed variable X, we can define X = X(φ, λ, h, this context, the EML data serve as a testbed for verifying the H, P, A, C). Here, φ, λ, h and H are determined from the results obtained from the Nanning data. HYSPLIT back trajectories, φ indicates the maximum and min- imum latitudes, λ gives the maximum and minimum longitudes, h represents the maximum and minimum altitudes, H is the 3 Results mixing depth of the planetary boundary layer, and P is the 24- h precipitation rate obtained from the United Kingdom 3.1 Time-Series Measurements Meteorological Office (UKMO) Hadley Centre. The data ana- 7 210 210 lyzed in this work are HadISD version 3.1.0.201911p (Dunn Time-series measurements of Be, Pb, and Po over et al. 2012, 2014, 2016). A is the AOI, which is the daily mean 39 months from 2014 to 2017 are shown in Fig. 2(a).The 7 3 data obtained from the National Centers for Environmental average specific activity of Be is 4.21 mBq/m and is in the Prediction (NCEP)/National Center for Atmospheric Research range of 0.39–12.70 mBq/m . The average specific activity of 210 3 (NCAR) reanalysis (Zhou et al. 2001), and C indicates the Pb is 1.51 mBq/m and is in the range of 0.23–3.92 mBq/ 3 210 3 ground-level cosmic ray observations obtained from the cosmic m . The average specific activity of Po is 0.61 mBq/m and 3 7 ray station of the Sodankyla Geophysical Observatory, is in the range of 0.17–1.68 mBq/m . The activity level of Be University of Oulu, Finland (Mishev et al. 2014). is higher than the global average level of 2.45 mBq/m3 based The daily AO index is obtained from the National Oceanic on long-term observations of more than 70 stations around the and Atmospheric Administration (NOAA) Climate Prediction world (Koch et al. 1996). The activity of Be is comparable to Center (ftp://ftp.cpc.ncep.noaa.gov/cwlinks/norm.daily.ao. that determined at other observation stations (EML data, as 210 210 index.b500101.current.ascii). The daily AO index is shown in Fig. 5). The activities of Pb and Po in the calculated via methods similar to Thompson and Wallace ambient aerosols mostly exceed the simulated values at 0.5 (2000) and Thompson et al. (2000). The daily AO index is and 0.05 mBq/m , respectively (UNSCEAR 2000). However, 210 210 determined by projecting the daily 1000 hPa height anomalies the activity levels of Pb and Po at Nanning are compa- at latitudes north of 20°N onto the leading empirical orthogo- rable to those over other cities in China (Pan et al. 2017). The nal function (EOF) (https://www.cpc.ncep.noaa.gov/products/ three nuclides exhibit a seasonal variation pattern: higher ac- precip/CWlink/daily_ao_index/ao.shtml). The monthly mean tivity in winter and lower activity in summer. The overall 7 210 210 1000 hPa height anomalies north of 20°N are used to construct concentration of Be is higher than that of Pb and Po, the EOF. The daily AO index is normalized by the standard and its fluctuation is also more notable. Rainfall is the main deviation of the monthly index (based on the 1979–2000 pe- process of aerosol removal from the atmosphere. Rainfall is riod). NCEP/NCAR reanalysis data at 2.5 degree longitude- abundant in the summertime in Nanning, which decreases 210 210 7 latitude resolution are used in the construction of the monthly Pb and Po, similar to Be. Although the production rate EOF (https://www.cpc.ncep.noaa.gov/products/precip/ of Be at any given latitude in the atmosphere does not change CWlink/daily_ao_index/history/method.shtml). The positive with the season, the seasonal intrusion of lower stratospheric AO index corresponds to negative height anomalies over the air and washout of atmospheric aerosols carrying Be leads to polar region, and vice versa (Thompson et al. 2000). the enrichment of Be during late winter and early spring, Korean Meteorological Society X. Chen et al. 210 210 (a) The activities of Pb and its progeny Po exhibit sea- sonal variation, with low concentrations in summer and high concentrations in winter. The back trajectory maps of Pb and Po are shown in Fig. 2(b). The back trajectories of the higher concentrations are overwhelmingly distributed over the land area. Oceanic air masses from the South China Sea play a dominant role in affecting the weather in Nanning in summer with negligible Rn activity, while the back trajectories of the land air masses in winter indicate higher Rn activity. 222 210 210 Therefore, the activity of the Rn, Pb and Po progenies exhibits the same seasonal distribution in aerosols (Carvalho 1995;Dueñas etal. 2011). 3.2 Correlation Analysis Figure 3(a) shows that the correlation between Be and the AOI is the most significant, with an R = 0.26, and the P value is 0.0268, followed by Pb, with an R = 0.20 and a P value of 0.0826. The correlation between Po and the AO is an R value of 0.29 and a P value of 0.0138. More noteworthy dis- (b) cussions are presented below. As a tracer of the STE, the 7 210 correlation of Be versus Pb is significant, with R = 0.62 and a P value <0.01 (Fig. 3(c)). Precipitation is negatively correlated with the Be concentration, with R = 0.30 and a P value = 0.11 (Fig. 3(b)). Note that Fig. 3(a) also shows that 7 2 low levels of Be (less than 1 mBq/m ) are also associated with a high AOI, indicating the involvement of multiple pro- Nanning 7 210 210 Be Pb Po cesses in the scatter diagram. 7 210 7 Fig. 2 a Time series of the activity of the three nuclides ( Be, Pb, and Figure 3(b) shows negative correlations between Be, Po), the AOI, earthquake events, cosmic rays, and precipitation in Pb and precipitation. The negative correlation between Nanning from 9/10/2014 to 10/12/2017; b trajectory map for (i) Be: 3 3 Pb and precipitation is characterized by R = 0.35 and a P green (0–3.0 mBq/m ), blue (3.0–6.0 mBq/m ), and red (6.0–9.0 mBq/ 3 210 3 3 value of 0.06, while Po shows no clear correlation with m ); (ii) Pb: green (0–1.0 mBq/m ), blue (1.0–2.0 mBq/m ), and red 3 210 3 210 (2.0–3.0 mBq/m ); (iii) Po: green (0–0.5 mBq/m ), blue (0.5–1.0 mBq/ precipitation. An earthquake is the source event for Pb 3 3 m ), and red (1.0–1.5 mBq/m ). The Nanning monitoring site is and Po. Due to crustal rupture, a high concentration of highlighted by bold white stars and arrows and is indicated in the central Rn can diffuse from crustal soil to the atmosphere. figure Therefore, seismic events may be able to explain the short- 210 210 term and sudden high-activity events of Pb and Po as which does not occur in summer (Marenco and Fontan 1974; long half-life progenies of Rn. However, seismic signals Feely et al. 1989;Du et al. 2020). are relatively complex and are not explained in this work. 7 7 Be is a cosmogenic radionuclide that is mainly produced To clarify the effect of the AO on Be, we perform a series in the stratosphere. Due to cosmic rays, Be is continuously of sensitivity tests with various durations (from 2 to 7 days) of produced. Ground-level cosmic ray observations revealed a the back trajectories. The test results reveal that the 6–7day persistent increasing trend from October 2014 to December back trajectories result in the most significant correlation (R = 7 7 2017. Despite increasing cosmic rays, the activity of Be in the 0.46 and P value <0.01) between Be and height. Hence, near-surface air did not persistently increase. Hence, the var- correlation analysis is performed on these four variables 7 7 iations in ground-level Be concentrations are more associated (AOI, Be, latitude, and altitude) by considering three AOI with AO patterns than with changes in the incoming cosmic cases (all, positive phase, and negative phase (see Fig. 4)). rays. The back trajectory analysis (Fig. 2(b)) clearly shows For data reliability, a comparison between the EML and that almost all of the higher concentrations of Be originate Nanning observation data is conducted via scatter plot analy- 7 210 7 from middle and high latitudes. Some of the trajectories start sis of Be versus AOI and of Pb versus Be. in polar regions. These back trajectories indicate that Be ob- Figure 4(a) shows that 63% (90/142) of the back trajecto- served near the ground in Nanning was affected by air from ries in the case of AOI > 0 originate in the NH polar region and middle and high northern latitudes mid-latitude regions. The back trajectories for AOI < 0 (37%) Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... 210 210 Fig. 3 Scatter plots of the observed variables versus the AOI. a The three Pb (central panel), and Po (right panel)) versus precipitation. c 7 210 210 210 7 210 radionuclides ( Be (left panel), Pb (central panel), and Po (right Correlations between Pb and Be (left panel) and between Po and 7 7 panel)) versus the AOI. b The three radionuclides ( Be (left panel), Be (right panel) are confined to latitudes south of 50°N. Both Be and the AOI panel). The correlation coefficient R increased to R = 0.48 in exhibit a significant correlation with the maximum altitudes the case of AOI > 0 (P value <0.01; Fig. 4(b),middle panel). and latitudes of the HYSPLIT back trajectories (Fig. 4(b, c, d, In terms of the AOI versus altitude, the R = 0.10 in the case of e)). Especially in the case of AO > 0, all the correlations are all AOI data (Fig. 4(c), left panel). The correlation coefficient more notable. Regarding the AOI versus latitude, the R = 0.28 R increased to R = 0.32 in the case of AO > 0 (P value<0.01; in the case of all AOI data (P value <0.01; Fig. 4(b), left Fig. 4(c),middle panel). Korean Meteorological Society X. Chen et al. Fig. 4 Scatter plots of Be measurements versus the highest altitudes and latitude. c All AOIs (left panel), positive AOIs (central panel), and latitudes of the air mass back trajectories from HYSPLIT. a Spatial negative AOIs (right panel) versus altitude. d Altitude versus Be for all distribution of the back trajectories: all AOIs (left panel), positive AOIs AOIs (left panel), positive AOIs (central panel), and negative AOIs (right (middle panel), and negative AOIs (right panel). b All AOIs (left panel), panel). e Latitude versus Be (left panel) and altitude versus latitude (right positive AOIs (central panel), and negative AOIs (right panel) versus panel) for positive AOIs The correlation between altitude and Be is significant, (P value <0.01; Fig. 4(d), middle panel). These results prove with R = 0.40 in the case of all AOI data (Fig. 4(d),leftpanel). that the sources of the elevated Be are located at high alti- The correlation coefficient is R = 0.37 in the case of AOI > 0 tudes. The correlations between latitude and Be (R = 0.56 in Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... Fig. 4 (continued). the case of AOI > 0, with a P value <0.01; Fig. 4(e),left panel) well as from the high to low latitudes. These processes explain 7 7 prove that elevated Be is associated with higher latitudes in why the AOI exhibits good correlations with Be. These four the NH. The latitude versus altitude correlations (R = 0.61, aspects ( Be, AOI, latitude, and altitude) are notably correlat- with a P value <0.01; Fig. 4(e), right panel) demonstrate that ed through analysis of the back trajectories. the high-latitude air masses originated from the NH high In summary, Fig. 4 demonstrates that elevated Be is asso- latitudes. ciated with air coming from high latitudes (polar regions) and The polar stratosphere exhibits the highest Be production high altitudes (lower stratosphere). In the case of AOI > 0, rate, while the tropical lower troposphere experiences the low- strong and positive regression correlations exist between lati- 7 7 est Be production rate (Feely et al. 1989). The variations in tude and altitude versus Be and between altitude versus lati- the AO exhibit chains of coupled flow pattern changes from tude. In the case of AOI < 0, a weak positive regression is the polar stratosphere downward toward the lower-latitude observed. All correlation coefficients are statistically signifi- troposphere. With the AO as a key mechanism, air parcels cant (P value<0.01 for positive phases of the AO). These move from higher latitudes and altitudes (the polar strato- results indicate that the air masses enriched in Be originate sphere that is rich in Be) to lower latitudes and altitudes from polar regions and the lower stratosphere. The distur- (the tropical troposphere) when the AO is positive, and East bance and variability of the polar vortex, exhibited as the Asia experiences a more notable STE. Therefore, it is easy to AOI, are the main causes of the elevated Be observed at the understand that with the higher altitudes and latitudes of the tropical Nanning site. HYSPLIT trajectories, it is more likely for the air enriched in The back-trajectory computation strongly supports our Be to be transported from the stratosphere to troposphere, as findings of the dominant role of the AO in controlling the Korean Meteorological Society X. Chen et al. Fig. 5 Scatter plots of EML data versus Nanning data. a At 7 210 Barrow, Be versus Pb, and (b) AOI versus Be. Panels (c)and (d)are thesameas (a) and (b)but for Montgomery, Alabama. Red crosses represent Nanning data, and red straight lines are linear regression model results. Blue crosses represent EML data, and blue straight lines are linear regression model results 7 7 abundance of Be (Fig. 3(a)) and the significant correlation In Perth (32°S), Australia, Be is correlated with the AOI 7 210 210 7 between Be and Pb (Fig. 3(c)). Moreover, based on the with an R = 0.11, and Pb is correlated with Be with an R = meteorology along the back trajectories, we perform further 0.36 (P < 0.01). In Tasmania (40.73°S), Australia, the Be correlation analyses (Fig. 4) and prove that the air masses versus AOI correlation has an R-value of 0.11, and the Pb 7 7 enriched in Be originate from the polar regions and the lower versus Be correlation has an R-value of 0.21 (p <0.01). On 210 7 stratosphere. Reunion Island (21.10°S), the Pb versus Be correlation has an R-value of 0.36 (P < 0.01). The comparisons show that similar latitudes exhibit similar ranges of Be concentrations 3.3 Comparisons with EML Data and correlation coefficients between 210Pb and Be (R = 0.31, P < 0.01), while the Pb correlation coefficient range is half For data reliability and to test our results, scatter plot of that at the Nanning site (due to abundant fossil fuel burn- 7 210 7 analysis of Be versus AOI and Pb versus Be was ing). The patterns from the 5 Australian sites are consistent, again performed on the EML data, which contains more which verifies that they are correct. than 6000 observations on a global scale. Figure 5 shows In the NH, many sites exhibit a very good linear correlation 210 7 the sites in the NH that have similar patterns as Nanning. between Pb and Be and are geographically associated with Figures 6 and 7 show the sites in the Southern large mountain ranges in the NH, such as the Himalayas, Alps, Hemisphere (SH) that exhibit both positive correlations and Rocky Mountains (Fig. 8(a)). The downwind areas of 7 7 210 between the AOI and Be and between Be and Pb. high mountains easily experience vertical air oscillations, thus The correlation analysis results are statistically significant. intensifying the instability of tropospheric air and increasing Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... Fig. 6 The same as Fig. 5, but for sites in the SH. Panels (a) and (b) are for Reunion Island. Panels (c) and (d) are for Norfolk, Australia. Panels (e) and (f) are for Perth, Australia 7 210 advection and the disturbance between the troposphere and between Be and Pb indicates that the disturbance of the stratosphere. As a tracer of the STE, the good coherence air due to high mountains can promote the coupling of the Korean Meteorological Society X. Chen et al. Fig. 7 The same as Fig. 6, but for sites in the SH. Panels (a) and (b) are for Tasmania, Australia. Panels (c) and (d) are for Chatham, New Zealand. Panels (e)and (f) are for Mawson, Antarctica stratosphere and troposphere. Interestingly, Nanning exhibit- that were higher than those at all the EML sites. Nanning is 7 210 7 ed correlations of both Be versus AOI and Pb versus Be located in the westerly disturbance area on the leeward side of Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... Fig. 8 Spatial distribution of EML sites with statistically significant correlations for the analyzed pairs: (a) Be versus 210 7 Pb and (b) AOI versus Be 7 7 210 the Himalayas, which is the highest mountain range on Earth. paired AOI versus Be and Be versus Pb represent the Hawaii, affected by the Himalayas, is downwind of Nanning. AO-initialized stratosphere-troposphere coupled effect. Montgomery, Alabama, is on the east coast of the US and experiences a relatively severe air disturbance due to the Rocky Mountains. In Barrow, Alaska, which is affected by 4 Discussion and Conclusions the Alaska Mountain Range, the correlations between Pb 7 7 and Be are also notable with R = 0.59 and a P value <0.01, In this work, we showed that the ground levels of Be and 210 210 and the lower Pb activity may be due to its coastal location. Pb at the Nanning and EML stations in Alaska (Barrow), The Montgomery site (32°N) in Alabama exhibits a good Montgomery (Alabama), Australia (Perth, Tasmania, and 210 7 correlation between Pb and Be, with R = 0.49 (P <0.01). Norfolk), New Zealand (Chatham), and American Samoa Figure 8(b) shows the sites that exhibit statistical signifi- were positively and statistically significantly correlated with 7 210 cance in the linear regression analysis of Be versus Pb. an increase in the positive AOI. What are the mechanisms 7 210 This figure shows the sites that are the most responsive and resulting in the surface Be and Pb being positively corre- reflect the highest degree of coupling between the stratosphere lated with the AOI? What processes that lead to Be were and troposphere during the positive phases of the AO. positively correlated with Pb at these sites? 7 7 At these sites, the correlations between Be and AOI and The production rates of Be are higher in the upper tropo- 210 7 7 −1 between Pb and Be are significant with P-values that are sphere and lower stratosphere (25–50 Be atoms s (gram of −1 7 −1 less than 0.05; these sites include Barrow, Alaska and air) ) than in the lower troposphere (1–5 Be atoms s (gram −1 Montgomery, Alabama in the USA, and Perth and Tasmania of air) ;Koch etal. 1996). Approximately two-thirds of the 7 7 in Australia. Note that Fig. 7(e) shows that both Nanning and Be is produced in the stratosphere, and one-third of the Be is Mawson Station in Antarctica have similar measurements of produced in the troposphere (Rehfeld and Heimann 1995). On 7 210 210 Be, but the Pb at Mawson is very low compared with that the other hand, Pb is produced from the radioactive decay 210 222 at Nanning. The higher Pb activity at the Nanning site is of Rn, which is released from terrestrial soil (Koch et al. mainly due to its location in an inland city as well as industrial 1996). Hence, only a small contribution of stratospheric air is influence. Mawson Station in Antarctica, which is far from needed to produce a large change in the observed Be in sur- continents, has very low Pb activity due to the reduction face air (Dutkiewicz and Husain, 1985). (decay and diffusion) in Pb during long-distance ground Figure 9 shows the difference in geopotential height (m) at dust transport from remote terrestrial areas. On the other hand, 850 hPa between years of positive AO (1989, 1990, 1992, the elevated Be over Mawson, Antarctica indicates the abun- 1993, 1997, and 2000) and years of negative AO (1980, dant sources of Be from the lower stratosphere over 1985, 1987, and 2001) calculated by Lamarque and Hess Antarctica. (2004). The positive geopotential anomalies are associated 7 210 The good correlations between Be and Pb represent the with the positive anomalies of high pressures and clockwise spatial distribution of observations dominated by stratosphere- circulations. Red curves encircle the regions of the anomalous troposphere coupled effects (Fig. 8(b)). The good correlations highs with high pressure centers highlighted by H ,H ,H , 1 2 3 between the AOI and Be represent the spatial distribution of and H .H is centered at approximately 120°E and 45°N 4 1 sites with the AO-initiated stratospheric effect in the tropo- (eastern Asian continent). H is centered around the North sphere (Fig. 8(a)). The combined good correlations of the Pacific, at 150°W and 60°N. The high-pressure systems are Korean Meteorological Society X. Chen et al. STE and downward transport of elevated potential vorticity (PV) and Be to the lower troposphere (Black 2002;James et al. 2003). The Nanning site is located downstream of the H high- pressure system, while the H high-pressure system influences the Barrow site in Alaska during the positive AO phases. The rest of the sites (Mauna Loa, three sites in Australia, two sites in New Zealand, and American Samoa) are located in regions with enhanced subsidence during the positive AO phases (Limpasuvan et al. 2005; Zhao and Miller 2005). The HYSPLIT model calculations show that the back tra- jectories tend to originate in the high altitudes of the tropo- sphere and with the origins of the trajectories in northern higher latitudes. These results are presented in the regression model analysis (altitudes are correlated with latitudes). The clockwise back trajectories are consistent with the subsidence of the flows associated with the high-pressure systems from northern high latitudes and high altitudes to the tropical Nanning site. Fig. 9 A schematic diagram showing the distribution of the anomalous We used NCEP reanalysis data to check the sensitivity of high- and low-pressure systems associated with differences between the the HYSPLIT results with respect to the meteorological data positive and negative AO years. The shaded colors indicate the distribu- tion of the anomalous high (red) and low (blue) pressure systems adapted used in this work. Fig. S2 compares the horizontal distribution from Lamarque and Hess (2004). The locations of the high-pressure sys- of the back trajectories calculated with the GDAS0p5 data tems are indicated by H ,H ,H ,and H . Schematic flow symbols indi- 1 2 3 4 (Fig. S2(a)) and with the NCEP reanalysis data (Fig. S2(b)). cate that the main low-pressure system, L, over the Arctic regions is We note that the GDAS0p5 data have a horizontal resolution added to demonstrate the flow patterns associated with the anomalous high- and low-pressure systems. The bottom panel shows a meridional of 0.5 degrees longitude-latitude and contain output data col- vertical circulation through the 120°E and 60°W cross-sections (indicated lected every 3 h on 55 hybrid sigma-pressure levels from the by the green line in the upper panel) associated with the anomalous high- surface to 13 hPa. The reanalysis data have a horizontal reso- and low-pressure systems lution of a 2.5 degree longitude-latitude grid, output data col- lected every 6 h, and 17 pressure levels (1000, 925, 850, 700, accompanied by subsidence flow from the upper troposphere 600, 500, 400, 300, 250, 200, 150, 100, 70, 50, 30, 20, and to the lower stratosphere. The lower panel of Fig. 9 shows 10 hPa). Fig. S2 shows that the general patterns of the gridded vertical circulations associated with the anomalous high- and distribution of the occurrence of back trajectories are similar. low-pressure systems. Hence, high-pressure systems are asso- However, the results calculated with GDAS0p5 data show a ciated with enhanced subsidence (Lee et al. 2004). They are more widespread distribution of the back trajectories than the conducive to the vertical transport of elevated Be from the results calculated with the reanalysis data. The GDAS0p5 data upper troposphere and lower stratosphere (UTLS) regions to have a higher horizontal and vertical resolution than the re- the lower troposphere. The subsidence associated with high- analysis data, resulting in a better representation of the vertical pressure systems also suppresses convection and precipitation velocity. The linear regression analysis of the AOI and Be processes in the atmospheric boundary layer, leading to the versus latitudes and altitudes calculated with the reanalysis enhancement of Pb at the surface (Rehfeld and Heimann data are consistent with the results calculated with the 1995;Koch etal. 1996;Wang et al. 1999). Hence, the devel- GDAS0p5 data. Elevated AOIs are associated with air origi- opment of the positive AOI is conducive to the transport of nating from northern higher latitudes (Fig. S3(a)). Elevated 7 7 elevated Be from the UTLS regions to the lower troposphere. Be is associated with air originating from northern higher The negative differences in the AOI are associated with the latitudes (Fig. S3(b)). The air from northern higher latitudes negative anomalies of the low pressure and anti-clockwise originates from elevated altitudes (Fig. S3(c)). Elevated AOIs circulations. They are associated with enhanced upward mo- are associated with air from higher altitudes (Fig. S3(d)). tion. The development of the anomalous low-pressure system, Elevated Be concentrations are associated with air originat- L, over the Arctic region acts to enhance the strength of the ing from higher altitudes (Fig. S3(e)). The altitudinal origins polar vortex (Thompson and Wallace 1998;Baldwin and of the air calculated with the reanalysis data are mostly limited Dunkerton 1999; Ambaum and Hoskins 2002). A developing to altitudes below 5 km (Fig. S3(d)), which are lower than the polar vortex produces atmospheric circulations similar to origins of the air calculated with the GDAS0p5 data (Fig. those of the AO patterns in Fig. 9 and is conducive for the 4(d)). These comparisons indicate that the vertical velocities Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... calculated from the coarse resolution of the reanalysis data are (Fig. S5(a)), and decreases in H O(Fig. S5(b)) and tempera- lower than the high resolution of the GDAS0p5 data. A sep- ture (Fig. S5(c)) occur in the troposphere. At Hong Kong, O arate study has evaluated the quality of the GDAS0p5 data for increases at altitudes below 7 km (Fig. S5(d)), and decreases back trajectory studies over East Asia. The calculations show in H O (Fig. S5(e)) and temperature (Fig. S5(f)) occur in the that elevated CO concentrations over North Pacific flight cor- troposphere. Hong Kong is located 580 km east of the ridors can be traced back to the ground level industrial areas Nanning site. Hong Kong has ozonesonde data that is closest over East Asia. In contrast, the back trajectories show that low to the Nanning site. In the middle of the North Pacific Hilo CO in the upper troposphere is associated only with the air in site, O increases at altitudes below 4 km and above 6 km in the upper troposphere, where the CO concentrations are low. the troposphere (Fig. S5(g)), H O decreases at altitudes below We note that Nanning has abundant precipitation leading to 2 km (Fig. S5(h)), and temperature decreases throughout the wet summers, and rainfall is the main removal process of troposphere (Fig. S5(i)). aerosols from the atmosphere. Therefore, the influence of re- We also used ozonesonde data from Hong Kong to test the moval of rainfall on radionuclides in aerosols should be taken sensitivity of the regression results when seasonal cycles were into account. Therefore, in Fig. 3(b), we considered the corre- excluded. The Be data cover 4 winters (2014, 2015, 2016, lation analysis of rainfall on the activity of the three nuclides. and 2017), while the ozonesonde data in Hong Kong cover a The negative correlations shown in Fig. 3(b) are consistent period of 20 years (2000–2020) and have 20 winters for anal- with previous works (e.g., Rehfeld and Heimann 1995; ysis. Fig. S5(d), (e), and (f) demonstrate that the profiles of O Koch et al. 1996), showing the wet scavenging effect of Be and H O trends and the increases in the AO over Hong Kong and Pb in Nanning. are consistent with the trends of 7Be that vary with AO over The dynamics of recent climate change have been linked to Nanning during the analysis period (December 2014– the Arctic (e.g., James et al. 2003). The North Atlantic December 2017). Analysis of the 20 years of data shows that Oscillation (NAO) and AO have become more positively biased O increased as the AO increased at altitudes below 7 km (Fig. since 1950 (e.g., Visbeck et al. 2001;Hurrell et al. 2004). As S6(a)), H O decreased as the AO increased at altitudes below 7 210 shown in this study, the levels of near-surface Be and Pb are 7km (Fig. S6(b)), and temperature decreased as the AO in- positively correlated with the increasing trends in the positive creased throughout the troposphere (Fig. S6(c)). When data 7 210 AO. Continuous measurements of near-surface Be and Pb only from the winter months (December, January, and can provide radioactive evidence for monitoring continuous February) are considered in the analysis, the results show that changes in the AO and the links to global warming. increases in O occur with increases in the AO at altitudes Based on previous works (Wang et al. 2002;Wangand below 3 km (Fig. S6(d)), and decreases in H O occur with Kau 2015 and references therein; and references cited in the increases in the AO at altitudes below 3 km (Fig. S6(e)). manuscript), we use the association between ground-level ob- Hence, the results in the lower troposphere show that the O served Be (a stratospheric tracer) and the AOI to indicate the and H O changes with the increases in AO are consistent changes in the STE associated with the AOI in this work. The between all data and winter-only data. Fig. S6(f) shows that air with stratospheric origins contains elevated Be, elevated temperatures are slightly increased in the troposphere with O ,low CO,and lowH O. Hence, we also analyze O ,H O, increases in the AO. This result is consistent with a longer 3 2 3 2 and temperature from ozonesonde measurements (WOUDC trend of increases in tropospheric temperatures associated 2021). Fig. S4 shows the linear regression model analysis of with global warming. O ,H O, and temperature versus AOI at three sites over the 3 2 North Pacific from 2014 to 2017. At an altitude of 3 km (to reduce the impact of ground-level photochemical O produc- Supplementary Information The online version contains supplementary tion), increases in O are associated with increases in the AOI material available at https://doi.org/10.1007/s13143-021-00237-2. at Taipei (25.00°N, 121.44°E; Fig. S4(a)), Hong Kong (22.31°N, 114.17°E; Fig. S4(d)), and Hilo, Hawaii Acknowledgments We gratefully acknowledge the NOAA Air (19.43°N, 155.04°W; Fig. S4(g)). In contrast, decreases in Resources Laboratory (ARL) for providing the HYSPLIT transport and dispersion model and/or the READY website http://www.arl.noaa.gov/ H O are associated with increases in the AOI at Taipei (Fig. ready.html used in this publication; the United States (US) Environmental S4(b)) and Hong Kong (Fig. S4(e)). H Oat Hilo (Fig. S4(h)) Measurements Laboratory (EML) for the global observational data was compounded by H O evaporation from the underlying (https://www.wipp.energy.gov/NAMP/EMLLegacy/databases.htm); the ocean. Additionally, an increase in AOIs are associated with United Kingdom Meteorological Office (UKMO) Hadley Centre HadISD version 3.1.0.201911p for the precipitation data (https://www. decreases in temperature in Taipei (Fig. S4(c)), Hong Kong metoffice.gov.uk/hadobs/hadisd/v310_201911p/download.html); the (Fig. S4(f)), and Hilo (Fig. S4(i)). Fig. S5 shows regression cosmic ray station of the Sodankyla Geophysical Observatory, analysis profiles throughout the troposphere, from the surface University of Oulu, Finland, for the cosmic ray data (https://cosmicrays. to an altitude of 10 km, with respect to increases in the AOI. oulu.fi/); and the China Earthquake Networks Center for the earthquake data (https://www.cenc.ac.cn/). The EML sample archives make At Taipei, O increases at altitudes of 3 km and above 5 km Korean Meteorological Society X. Chen et al. available environmental radiological data collected for programs funded health effects, ACS Symposium Series, 331, pp. 377–397. through the U.S. Atomic Energy Commission, the U. S. Energy Research American Chemical Society, Washington, D.C. (1987) and Development Administration and the U. S. Department of Energy. Bourcier, L., Masson, O., Laj, P., Pichon, J.M., Paulat, P., Freney, E., All of these programs have been terminated. The databases were last Sellegri, K.: Comparative trends and seasonal variation of 7Be, updated in 1999. No additional data will be added to these databases. 210Pb and 137Cs at two altitude sites in the central part of France. Any inquiries about these programs should be made to webmaster@ J. Environ. Radioact. 102(3), 294–301 (2011) eml.st.dhs.gov. We greatly benefited from the sampling support and Bronson, F.L.: Validation of the accuracy of the LabSOCS software for data provided by the Radiation-Environment Management and mathematical efficiency calibration of Ge detectors for typical lab- Monitoring Station of the Guangxi Zhuang Autonomous Region, oratory samples. J. Radioanal. Nucl. Chem. 255(1), 137–141 (2003) Nanning 530222, China (http://nnsa.mee.gov.cn/zjjg/pcjg/201501/ Brost, R.A., Feichter, J., Heimann, M.: Three-dimensional modeling of t20150107_305223.html; https://sthjt.gxzf.gov.cn). The Nanning data the concentration and deposition of Pb aerosols. J. Geophys. Res. reported in this work are shown in Table 1. KYW was funded under 96, 22,423–22,445 (1991) 222 210 210 108-2111-M-008-034. Carvalho, F.P.: Origins and concentrations of Rn, Pb, Bi and Po in the surface air at Lisbon, Portugal, at the Atlantic edge of the European continental landmass. Atmos. Environ. 29(15), 1809– Open Access This article is licensed under a Creative Commons 1819 (1995) Attribution 4.0 International License, which permits use, sharing, adap- Chen, W., Lan, X.Q., Wang, L., Ma, Y.: The combined effects of the tation, distribution and reproduction in any medium or format, as long as ENSO and the Arctic oscillation on the winter climate anomalies in you give appropriate credit to the original author(s) and the source, pro- East Asia. Chin. Sci. Bull. 58(12), 1355–1362 (2013). https://doi. vide a link to the Creative Commons licence, and indicate if changes were org/10.1007/s11434-012-5654-5 made. The images or other third party material in this article are included Cristofanelli, P., Bonasoni, P., Tositti, L., Bonafé, U., Calzolari, F., in the article's Creative Commons licence, unless indicated otherwise in a Evangelisti, F., Sandrini, S., Stohl, A.: A 6-year analysis of strato- credit line to the material. If material is not included in the article's spheric intrusions and their influence on ozone at Mt. Cimone (2165 Creative Commons licence and your intended use is not permitted by m above sea level). J. Geophys. Res. 111, D03306 (2006). https:// statutory regulation or exceeds the permitted use, you will need to obtain doi.org/10.1029/2005JD006553 permission directly from the copyright holder. To view a copy of this Cristofanelli, P., Bonasoni, P., Carboni, G., Calzolari, F., Casarola, L., licence, visit http://creativecommons.org/licenses/by/4.0/. Zauli Sajani, S., Santaguida, R.: Anomalous high ozone concentra- tions recorded at a high mountain station in Italy in summer 2003. Atmos. Environ. 41,1383–1394 (2007) References Cristofanelli, P., Calzolari, F., Bonafé, U., Duchi, R., Marinoni, A., Roccato, F., Tositti, L., Bonasoni, P.: Stratospheric intrusion index (SI2) from baseline measurement data. Theor. Appl. Climatol. 97, Ambaum, M.H., Hoskins, B.J.: The NAO troposphere-stratosphere con- 317–325 (2009) nection. J. Clim. 15,1969–1978 (2002) Cutlip, K.: Northern influence. Weatherwise. 53(2), 10–11 (2000) Baldwin, M.P., Dunkerton, T.J.: Propagation of the Arctic oscillation Daish, S.R., Dale, A.A., Dale, C.J., May, R., Rowe, J.E.: The temporal from the stratosphere to the troposphere. J. Geophys. Res. 210 210 variations of 7Be, Pb and Po in air in England. J. Environ. 104(D24), 30,937–30,946 (1999) Radioact. 84(3), 457–467 (2005). https://doi.org/10.1016/j.jenvrad. Balkanski, Y.J., Jacob, D.J., Gardner, G.M., Graustein, W.C., Turekian, 2005.05.003 K.K.: Transport and residence times or tropospheric aerosols in- Deng, Q., Wei, Y., Zhao, Y., Han, X., Yin, J.: Understanding the natural ferred from a global three-dimensional simulation of Pb. J. and socioeconomic factors behind regional longevity in Guangxi, Geophys. Res. 98, 20573–20586 (1983) 210 210 210 China: Is the centenarian ratio a good enough indicator for assessing Baskaran, M.: Po and Pb as atmospheric tracers and global Pb the longevity phenomenon? Int. J. Environ. Res. Public Health. fallout: a review. J. Environ. Radioact. 102,500–513 (2011) 15(5), pii: E938 (2018). https://doi.org/10.3390/ijerph15050938 Baskaran, M., Shaw, G.E.: Residence time of arctic haze aerosols using 210 210 Dibb, J.E., Talbot, R.W., Gregory, G.L.: Beryllium 7 and lead 210 in the the concentrations and activity ratios of Po, Pb and 7Be. J. western hemisphere Arctic atmosphere: observations from three re- Aerosol Sci. 32(4), 443–452 (2001). https://doi.org/10.1016/ cent aircraft-based sampling pograms. J. Geophys. Res. 97(D15), S0021-8502(00)00093-8 16709 (1992). https://doi.org/10.1029/91jd01807 Bhandari, N., Lal, D.: Vertical structure of the troposphere as revealed by radioactive tracer studies. J. Geophys. Res. 75,2974–2980 (1970) Done, L., Tugulan, L.C., Gurau, D., Dragolici, F., Alexandru, C.: Black, R.X.: Stratospheric forcing of surface climate in the artic oscilla- Comparison of LabSOCS and GESPECOR codes used in gamma- tion. J. Clim. 15(1), 268–277 (2002) ray spectrometry. International Conference on Radionuclide Metrology & Its Applications. 109,539–543 (2016) Bonasoni, P., Evanegelisti, F., Boanfé, U., Feldmann, H., 7 210 Du, J., Baskaran, M., Du, J.: Atmospheric deposition of Be, Pb and Memmesheimer, M., Stohl, A., Tositti, L.: Stratosphere- Po during typhoons and thunderstorm in Shanghai, China and troposphere exchanges: case studies recorded at Mt. Cimone during global data synthesis. Sci. China Earth Sci. 63(4), 602–614 (2020). VOTALP project. Physics and Chemistry of the Earth, Parts C. https://doi.org/10.1007/s11430-019-9481-9 24(5), 443–446 (1999) Bonasoni, P., Evangelisti, F., Bonafé, U., Ravegnani, F., Calzolari, F., Dueñas, C., Orza, J.A.G., Cabello, M., Fernández, M.C., Cañete, S., Stohl, A., Tositti, L., Tubertini, O., Colombo, T.: Stratospheric Pérez, M., Gordo, E.: Air mass origin and its influence on radionu- 7 210 ozone intrusion episodes recorded at Mt. Cimone during VOTALP clide activities ( Be and Pb) in aerosol particles at a coastal site in project: case studies. Atmos. Environ. 34,1355–1365 (2000a) the western Mediterranean. Atmos. Res. 101(1–2), 205–214 (2011). Bonasoni, P., Stohl, A., Cristofanelli, P., Calzolari, F., Colombo, T., https://doi.org/10.1016/j.atmosres.2011.02.011 Evangelisti, F.: Background ozone variations at Mt Cimone station. Dunn, R. J. H., Willett, K.M., Thorne, P.W., Wooley, E.V., Durre, I., Atmos. Environ. 34,5183–5189 (2000b) Dai., A., et al. (2012). HadISD: a quality-controlled global synoptic Bondietti, E.A., Papastefanou, C., Rangarajan, C.: Aerodynamic size as- report database for selected variables at long-term stations from sociations of natural radioactivity with ambient aerosols. In: Hopke, 1973–2011, Clim. Past, 8, 1649–1679, https://doi.org/10.5194/cp- P.K. (ed.) Radon and is decay products: occurrence, properties and 8-1649-2012 Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... Dunn, R.J.H., Willett, K.M., Morice, C.P., Parker, D.E.: Pairwise homo- model. J. Geophys. Res. Atmos. 101(13), 18651–18666 (1996). geneity assessment of HadISD. Clim. Past. 10,1501–1522 (2014). https://doi.org/10.1029/96jd01176 https://doi.org/10.5194/cp-10-1501-2014 Lal, D., & Peters, B. (1967). Cosmic ray produced radioactivity on the Dunn, R.J.H., Willett, K.M., Parker, D.E., Mitchell, L.: Expanding Earth. In: Sitte K. (Eds) Kosmische Strahlung II / Cosmic Rays II. HadISD: quality-controlled, sub-daily station data from 1931. Handbuch der Physik / Encyclopedia of Physics, Vol 9 / 46 / 2. Geoscientific Instrumentation Methods and Data Systems. 5,473– Springer, Berlin, Heidelberg 491 (2016). https://doi.org/10.5194/gi-5-473-2016 Lamarque, J.-F., Hess, P.G.: Arctic oscillation modulation of the northern Dutkiewicz, V. A., & Husain, L. (1985). Stratospheric and tropospheric hemisphere spring tropospheric ozone. Geophys. Res. Lett. 31(6), component of 7Be in surface air. J. Geophys. Res. 90,5783–5788. L06127 (2004). https://doi.org/10.1029/2003gl019116 Feely, H.W., Larsen, R.J., Sanderson, C.G.: Factors that cause seasonal Larsen, R.J., Sanderson, C.G., & Kada, J. (1995). EML surface air sam- variations in Beryllium-7 concentrations in surface air. J. Environ. pling program, 1990–1993 data. EML Report 572, 37–40, Radioact. 9(3), 223–249 (1989). https://doi.org/10.1016/0265- Environmental Measurements Laboratory, U.S. Department of 931X(89)90046-5 Energy, New York Gong, D.Y., Wang, S.W., Zhu, J.H.: East Asian winter monsoon and Lee, H.N., Wan, G., Zheng, X., Sanderson, C.G., Josse, B., Wang, et al.: 210 7 Arctic oscillation. Geophys. Res. Lett. 28,2073–2076 (2001) Measurements of Pb and Be in China and their analysis accom- 7 210 210 Graustein, W.C., Turekian, K.K.: Be and Pb indicate an upper tropo- panied with global model calculations of Pb. J. Geophys. Res. sphere source for elevated ozone in the summertime subtropical free 109, D22203 (2004). https://doi.org/10.1029/2004JD005061 troposphere of the eastern North Atlantic. Geophys. Res. Lett. 23, Lee, H.N., Tositti, L., Zheng, X., Bonasoni, P.: Analyses and compari- 7 210 7 210 539–542 (1996) sons of variations of Be, Pb, and Be/ Pb with ozone observa- tions at two global atmosphere watch stations from high mountains. Grossi, C., Ballester, J., Serrano, I., Galmarini, S., Camacho, A., Curcoll, J. Geophys. Res. 112, D05303 (2007). https://doi.org/10.1029/ R., Morguí, J.A., Rodò, X., Duch, M.A.: Influence of long-range 2006JD007421 atmospheric transport pathways and climate teleconnection patterns 210 7 on the variability of surface Pb and Be concentrations in south- Leppänen, A.P., Pacini, A.A., Usoskin, I.G., Aldahan, A., Echer, E., western Europe. J. Environ. Radioact. 165,103–114 (2016) Evangelista, H., Klemola, S., Kovaltsov, G.A., Mursula, K., Holton, J.R., Haynes, P.H., McIntyre, M.E., Douglass, A.R., Pfister, L.: Possnert, G.: Cosmogenic Be in air: a complex mixture of produc- Stratosphere-troposphere exchange. Rev. Geophys. 33(4), 403–439 tion and transport. J. Atmos. Sol. Terr. Phys. 72(13), 1036–1043 (1995) (2010). https://doi.org/10.1016/j.jastp.2010.06.006 Li, Y., Geng, X.C.: Effect of sample thickness on determination of Cs Hoskins, B.J., McIntyre, M.E., Robertson, A.W.: On the use and signif- and Pb using LabSOCS. Atomic Energy ence & Technology. icance of isentropic potential vorticity maps. Q. J. R. Meteorol. Soc. 44(1), 80–83 (2010) 111,877–946 (1985) 226 228 2l0 40 Hotzl, H., Winkler, R.: Activity concentrations of Ra, Ra, Pb, K Limpasuvan, V., Hartmann, D.L., Thompson, D.W.J., Jeev, K., Yung, and Be and their temporal variations in surface air. J. Environ. Y.L.: Stratosphere-troposphere evolution during polar vortex inten- Radioact. 5,445–5,458 (1987) sification. J. Geophys. Res. 110, D24101 (2005). https://doi.org/10. 1029/2005JD006302 Huh, C.A., Su, C.C.: Sedimentation dynamics in the East China Sea 210 137 239,240 elucidated from Pb, Cs and Pu. Mar. Geol. 160(1–2), Lozano, R.L., Hernández-Ceballos, M.A., Rodrigo, J.F., San Miguel, E.G., Casas-Ruiz, M., García-Tenorio, R., Bolívar, J.P.: Mesoscale 183–196 (1999). https://doi.org/10.1016/S0025-3227(99)00020-1 7 210 behavior of Be and Pb in superficial air along the gulf of Cadiz Hurrell, J.W.: Decadal trends in the North Atlantic oscillation region (south of iberian peninsula). Atmos. Environ. 80,75–84 (2013). temperatures and precipitation. Science. 269,676–679 (1995) https://doi.org/10.1016/j.atmosenv.2013.07.050 Hurrell, J. W., Kushnir, Y., Ottersen, G., & Visbeck, M. (2003). The Maenhaut, W., Zoller, W.H., Coles, D.G.: Radionuclides in the south North Atlantic oscillation: climate significance and environmental pole atmosphere. J. Geophys. Res. 84,3131–3138 (1979) impact. Geophysical monograph series, vol. 134, AGU, 7 32 90 210 Washington, D. C Marenco, A., Fontan, J.: Etude des variations des Be, P, Sr, Pb et Hurrell, J., Hoerling, M.P., Phillips, A.S., Xu, T.: Twentieth century Po dans la troposphere. Tetlus. 26,386–401 (1974) North Atlantic climate change. Part 1: assessing determinism. Matthews, K.M., Kim, C.K., Martin, P.: Determination of Po in envi- Clim. Dyn. 23,371–389 (2004) ronmental materials: a review of analytical methodology. Appl. Radiat. Isot. 65(3), 267–279 (2007). https://doi.org/10.1016/j. James, P., Stohl, A., Forster, C., Eckhardt, S., Seibert, P., Frank, A.: A 15- apradiso.2006.09.005 year climatology of stratosphere-troposphere exchange with a Lagrangian particle dispersion model. 2. Mean climate and seasonal Mishev, A.L., Kocharov, L.G., Usoskin, I.G.: Analysis of the ground variability. J. Geophys. Res. 108(D12), 8522 (2003). https://doi.org/ level enhancement on 17 May 2012 using data from the global 10.1029/2002JD002639 neutron monitoring network. J. Geophys. Res. Space Physics. 119, Jaworowski, Z., Kownacka, L., Bysiek, M.: Global distribution and 670–679 (2014). https://doi.org/10.1002/2013JA019253 sources of uranium, Radium-226, and Lead-210. In: Natural Pan, J.S., Wen, F.P., Chen, L., Ren, X.N., Zhang, J., Zhao, S.P., et al.: Radiation Environment III, vol. 1, pp. 383–404. Technical Preliminary analysis of activity concentration distributions of air- 210 210 Information Center, US Dept of Energy, Springfield (1980) borne Po and Pb in major cities in China. Radiation Protection. 37(6), 433–437 (2017) Jeong, J.H., Ho, C.H.: Changes in occurrence of cold surges over East Asia in association with Arctic oscillation. Geophys. Res. Lett. 32, Papastefanou, C.: Beryllium-7 aerosols in ambient air. Aerosol Air Qual. L14704 (2005) Res. 9(2), 187–197 (2009). https://doi.org/10.4209/aaqr.2009.01. Jevrejeva, S., Moore, J.: Singular spectrum analysis of Baltic Sea ice 0004 conditions and large-scale atmospheric patterns since 1708. Papastefanou, C., Ioannidou, A.: Aerodynamic size association of Be in Geophys. Res. Lett. 28(23), 4503–4506 (2001) ambient aerosols. J. Environ. Radioact. 26,273–282 (1995) Johnson, W., Viezee, W.: Stratospheric ozone in the lower troposphere: i. Press, W.H., Teukolsky, S.A., Vetterling, W.T., & Flannery, B.P. (1992). presentation and interpretation of aircraft measurements. Atmos. Numerical recipes in Fortran 77, 2nd ed., 933pp, Cambrideg Environ. 15,1309–1323 (1981) University Press, Cambridge, UK 210 7 Koch, D.M., Jacob, D.J., Graustein, W.C.: Vertical transport of tropo- Rastogi, N., Sarin, M.M.: Atmospheric Pb and Be in ambient aerosols 7 210 spheric aerosols as indicated by Be and Pb in a chemical tracer over low- and high-latitude sites in semiarid region: temporal Korean Meteorological Society X. Chen et al. variability and transport processes. J. Geophys. Res. Atmos. Visbeck, M.H., Hurrell, J.W., Polvani, L., Cullen, H.M.: The North 113(11), 1–14 (2008). https://doi.org/10.1029/2007JD009298 Atlantic oscillation: past, present, and future. Proc. Natl. Acad. Rehfeld, S., Heimann, M.: Three dimensional atmospheric transport sim- Sci. 98, (2001). https://doi.org/10.1073/pnas.231391598 ulation of the radioactive tracers 210Pb, 7Be, 10Be, and 90Sr. J. Wang, K.-Y., Chau, T.-T.: An association between air pollution and daily Geophys. Res. 100(D12), 26,141–26,161 (1995) outpatient visits for respiratory disease in a heavy industry area. San Miguel, E.G., Hernández-Ceballos, M.A., García-Mozo, H., Bolívar, PLoS One. 8(10), e75220 (2013). https://doi.org/10.1371/journal. J.P.: Evidences of different meteorological patterns governing Be pone.0075220 and Pb surface levels in the southern Iberian Peninsula. J. Wang, K.-Y., Kau, W.S.: Simulation of impact from stratospheric ozone Environ. Radioact. 198(December 2018), 1–10 (2019). https://doi. on global tropospheric ozone distribution with a chemistry transport org/10.1016/j.jenvrad.2018.12.007 model: a case study during the 1990-1991 period. Asia-Pac. J. Stein, A.F., Draxler, R.D., Rolph, G.D., Stunder, B.J.B., Cohen, M.D., Atmos. Sci. 51(2), 137–155 (2015) Nqan, F.: NOAA's HYSPLIT atmospheric transport and dispersion Wang, K.-Y., Pyle, J.A., Sanderson, M.G., Bridgeman, C.: modeling system. Bull. Am. Meteorol. Soc. 96,2059–2077 (2016) Implementation of a convective atmospheric boundary layer scheme Thompson, D.W.J., Lorenz, D.J.: The signature of the annular modes in in a tropospheric chemistry transport model. J. Geophys. Res. the tropical troposphere. J. Clim. 17(22), 4330–4342 (2004). https:// 104(D19), 23,729–23,745 (1999) doi.org/10.1175/3193.1 Wang, K.-Y., Shallcross, D.E., Pyle, J.A.: Seasonal variations and verti- Thompson, D.W.J., Wallace, J.M.: The Arctic oscillation signature in the cal movement of the tropopause in the UTLS region. Ann. Geophys. wintertime geopotential height and temperature fields. Geophys. 20(6), 871–874 (2002) Res. Lett. 25(9), 1297–1300 (1998). https://doi.org/10.1029/ WOUDC. (2021). Dataset information: OzoneSonde. Would Ozone and 98GL00950 Ultraviolet Radiation Data Centre. https://geo.woudc.org/def/data/ Thompson, D.W.J., Wallace, J.M.: Annular modes in the extratropical ozone/vertical-ozone-profile/ozonesonde, Version 1.30.0, doi: circulation. Part I: month-to-month variability. J. Clim. 13(5), 1000– https://doi.org/10.14287/10000008 1016 (2000) Wu, B.Y., Wang, J.: Winter Arctic oscillation, Siberian high and east Thompson, D.W.J., Wallace, J.M.: Regional climate impacts of the north- Asian winter monsoon. Geophys. Res. Lett. 29, 1897 (2002) ern hemisphere annular mode. Science. 293(5527), 85–89 (2001). Zhang, W., Chen, J., Ungar, K., Cooke, M.: Estimation of the Arctic https://doi.org/10.1126/science.1058958 aerosols from local and long-range transport using relationships be- Thompson, D.W., Wallace, J.M., Hegerl, G.C.: Annual modes in the 210 212 tween Pb and Pb atmospheric activity concentrations. J. extratropical circulation. Part II: Trends. J. Clim. 13,1018–1036 Environ. Radioact. 141,123–129 (2015) (2000) Zhao, S., Miller, A.J.: The interaction of the madden-Julian oscillation Tositti, L., Hübener, S., Kanter, H.J., Ringer, W., Sandrini, S., Tobler, L.: and the Arctic oscillation. J. Clim. 18,143–159 (2005) Intercomparison of sampling and measurement of Be in air at four Zheng, X., Wang, G., Tang, J., Zhang, X., Yang, W., Lee, H.N., et al.: high-altitude locations in Europe. Appl. Radiat. Isot. 61,1497–1502 7 210 Be and Pb radioactivity and implications on sources of surface (2004) 7 210 ozone at Mt. Waliguan. Chin. Sci. Bull. 50(2), 167–171 (2005) Turekian, K.K., Benninger, L.K., Dion, E.P.: Be and Pb total depo- sition fluxes at New Haven Connecticut and at Bermuda. J. Zhou, S., Miller, A.J., Wang, J., Angell, J.K.: Trends of NAO and AO Geophys. Res. 88,5411–5415 (1983) and their associations with stratospheric processes. Geophys. Res. UNSCEAR. (2000). Sources and effects of ionizing radiation, United Lett. 28,4107–4110 (2001) Nations Scientific Committee on the effects of atomic radiation UNSCEAR 2000 report to the general assembly, with scientific Publisher’sNote Springer Nature remains neutral with regard to jurisdic- annexes. In UNSCEAR 2000 Report: Vol. I tional claims in published maps and institutional affiliations. Usoskin, I.G., Kovaltsov, G.A.: Production of cosmogenic Be isotope in the atmosphere: full 3-D modeling. J. Geophys. Res. Atmos. 113(12), 1–12 (2008). https://doi.org/10.1029/2007JD009725 Korean Meteorological Society http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png "Asia-Pacific Journal of Atmospheric Sciences" Springer Journals

Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from Atmospheric Aerosols in a Remote Tropical Region in East Asia

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Abstract

The Arctic Oscillation (AO) accounts for a large fraction of recent decadal climate trends in Northern Hemisphere (NH) high latitudes. In East Asia, an elevated AO index (AOI) was associated with warmer temperatures in middle- to high-latitude regions, colder temperatures over low-latitude regions, and elevated ozone intrusion from the stratosphere. Elevated beryllium-7 ( Be) is produced in the stratosphere. Few studies have discussed the relationship between Be and the AO. Here, we identify the AO signature in Be and lead (Pb)-210 observed at a tropical ambient monitoring site in Nanning (22.8°N, 108.5°E) during the 7 210 December 2014–December 2017 period. Our results show that the Be and Pb concentrations are positively and significantly 7 210 correlated with the AOI (P < 0.01). These results show that elevated Be and Pb are associated with an increase in the AOI, reflecting air masses originating from NH high latitudes and vertically from the high-latitude upper troposphere and lower stratosphere regions to tropical latitudes in East Asia. These results have been verified with ozonesonde data without seasonality and with two meteorological data sets. Our results are also confirmed by observational data over the Pacific regions. We conclude that the AO exerts impacts over the tropical regions in East Asia, and Be can be used as a tracer to track the impacts of the AO. . . . . Keywords Beryllium-7 Lead-210 Arctic oscillation Atmospheric aerosols Nanning 1 Introduction winter and spring (Thompson and Wallace 2000;Hurrell et al. 2003). Its variability is commonly manifested by a sea- The Arctic Oscillation (AO) is the primary reason for the level pressure (SLP) difference between stations in the Azores interannual variability in the troposphere and lower strato- (Portugal) and Iceland (Thompson and Wallace 1998; Cutlip sphere. The AO affects the extratropical surface climate vari- 2000; Thompson and Wallace 2000; Thompson and Wallace ability in the Northern Hemisphere (NH), especially during 2001; Thompson and Lorenz 2004). The AO initially ema- nates from the stratosphere and ultimately alters surface weather, subsequently affecting the temperature and precipi- Responsible Editor: Jong-Seong Kug. tation in most NH areas. Hence, the AO is closely related to the frequency and intensity of extreme weather events * Kuo-Ying Wang (Thompson and Wallace 1998; Thompson and Wallace kuoying@mail.atm.ncu.edu.tw 2000; Thompson and Wallace 2001; Black 2002;Thompson and Lorenz 2004). School of Marine Sciences, Guangxi University, Nanning 530004, China In particular, the AO accounts for a large fraction of recent decadal climate trends in high northern latitudes (Hurrell College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China 1995;Thompson et al. 2000). Thompson et al. (2001) found 3 that in recent decades, the continuous high trend of the North Guangxi Laboratory on the Study of Coral Reefs in the South China Sea, Nanning 530004, China Atlantic Oscillation (NAO, which can be viewed as an AO subset (Jevrejeva and Moore 2001)) is an important reason for Radiation-Environment Management and Monitoring Station of Guangxi Zhuang Autonomous Region, Nanning 530222, China winter warming in the NH. In East Asia, as the winter AO index increases from low to high, the temperatures in the Department of Atmospheric Sciences, National Central University, Chung-Li District Taoyuan City, Taiwan middle- and high-latitude regions of the Asian continent Korean Meteorological Society X. Chen et al. become warmer, the low-latitude regions become colder, and this can produce radium, (Ra)-226, and radon, (Rn)-222, vice versa (Wu and Wang 2002;Gongetal. 2001; Jeong and which are precursors of lead, (Pb)-210 ( Pb). Due to the 222 210 Ho 2005;Chen etal. 2013). continental origin of Rn, Pb is considered a tracer of Beryllium-7 ( Be) is a sensitive indicator of stratospheric air masses with continental origins (Balkanski et al. 1983; air intrusion into the troposphere and this radionuclide is clas- Turekian et al. 1983;Baskaran 2011). Rn emanates sically applied in the stratosphere-troposphere exchange primarily from rocks and minerals in the crust. (STE) (Dibb et al. 1992; Bonasonietal. 1999, 2000a, b; Therefore, the spatial variability of Pb is strongly de- Cristofanelli et al. 2007, 2006, 2009). In contrast, Pb has pendent on the geographical types of terrestrial surfaces, been used as a continental tracer of air masses and long-range and the Rn flux from the ocean is negligible (San transport of chemical constituents (derived from continental Miguel et al. 2019). 210 210 sources) (Balkanski et al. 1983;Turekianetal. 1983; Po and Pb nuclides are concentrated in the air Baskaran 2011). The cosmogenic radionuclide Be (its half- over inland cities and industrial areas because of artificial life is 53.3 days) is produced by high-energy spallation inter- sources, such as industrial mining, automobile exhaust actions between galactic cosmic-ray (GCR)-produced neu- and construction dust (burning of coal, use of phosphate trons and protons (secondary particles) and atmospheric nu- fertilizers, car exhaust, and fires) (Jaworowski et al. 1980; clei (primarily nitrogen, oxygen and argon) (Lal and Peters Hotzl and Winkler 1987;Lozanoetal. 2013). Once 7 210 210 1967;UNSCEAR 2000; Usoskin and Kovaltsov 2008; formed in the air, Be, Pb, and Po are rapidly com- Papastefanou 2009;see Fig. S1). bined with submicron-sized aerosol particles (Maenhaut Increased ozone over much of Asia results from the posi- et al. 1979; Bondietti et al. 1987; Papastefanou 2009). tive phase of the AO combined with changes in the Hence, their concentrations in air are similar to those of stratosphere-troposphere exchange (STE; Holton et al. 1995; aerosol particles and depend on atmospheric transport and Wang et al. 2002; Wang and Kau 2015) that are responsible wet and dry removal (Papastefanou and Ioannidou 1995; for the correlation pattern between ozone and AO at 800 hPa Baskaran 2011). (Lamarque and Hess 2004). This study shows that the tropo- Because of the different sources of the two radionu- 7 210 spheric ozone concentration over Asia is affected by the in- clides, simultaneous measurements of Be and Pb and trusion of stratospheric ozone. Similar to air containing ele- their ratios can be implemented to identify the origin of vated ozone levels in the stratosphere, an elevated Be level air masses (Graustein and Turekian 1996;Bonasonietal. occurs in the stratosphere. Hence, Be is a stratospheric tracer 2000a, b; Zheng et al. 2005) and to study the vertical that can be directly or indirectly influenced by the AO. motion of air masses and convective activity in the tropo- Similar to Be, ozone from the stratosphere is consid- sphere (Brost et al. 1991;Kochetal. 1996; Lee et al. ered an indicator of the Arctic Oscillation (Thompson and 2004; Tositti et al. 2004; Lee et al. 2007). Moreover, Wallace 2000; Lamarque and Hess 2004;Dibbetal. temporal and spatial variations in this ratio reflect both 1992). However, few studies have discussed the relation- vertical and horizontal transport in the atmosphere ship between Be and the Arctic Oscillation. It is worth (Koch et al. 1996;Baskaran 2011). Due to their half- 7 210 7 discussing whether Be can be used as a tracer to track the lives (22.3 years for Pb and53.2daysfor Be), both Arctic Oscillation and whether the signal of the Arctic natural radionuclides can persist long enough for long- Oscillation can be discovered through aerosol data in the range transport in the atmosphere (Zhang et al. 2015; tropics to study the mechanism of climate teleconnection. Grossi et al. 2016;San Migueletal. 2019). Production of Be is the highest in the stratosphere (75%), In this paper, we report a three-year (2014/10–2017/12) 7 210 while the remaining part (25%) is produced in the upper study conducted on the abundance of Be, Pb, and troposphere (Johnson and Viezee 1981; UNSCEAR 2000; Po in the surface air over tropical urban site Nanning, Usoskin and Kovaltsov 2008). Be production increases China (22.8°N, 108.5°E). In addition, the interrelationship with altitude and geomagnetic latitude and is also associ- among these nuclides and a suite of related environmental ated with the 11-year solar cycle that modulates cosmic- factors, such as the AO, precipitation, cosmic rays, and ray penetration through the Earth’s magnetic field (Lal earthquakes, are also investigated. This paper adopts the and Peters 1967; Bhandari and Lal 1970;Dibbetal. Hybrid Single-Particle Lagrangian Integrated Trajectory 1992;UNSCEAR 2000; Usoskin and Kovaltsov 2008). (HYSPLIT) model to calculate the origins of air masses The polar stratosphere experiences the highest production reaching the Nanning sampling site, compares the rate, and the tropical lower troposphere exhibits the low- Nanning results to Environmental Measurements est production rate (Feely et al. 1989). Laboratory (EML) observations, and applies a regression Pb (with a half-life of 22.3 years) and its progeny model to study the correlations among the variables of polonium, (Po)-210, originate from the naturally occur- AOI, precipitation, air mass origin (latitude, longitude, 7 210 ring radionuclide uranium, (U)-238, in the environment; and altitude), Be, and Pb. Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... Table 1 Abundances of Be, 210 210 7 3 210 210 Code Start time* Finish time* Po(mBq/ Pb(mBq/ Be (mBq/m ) Pb, and Po in ambient 3 3 m ) m ) aerosols over Nanning 1 09.10.2014, / 10.10.2014, / 0.55 3.92 12.7 2 04.11.2014, / 05.11.2014, / 0.52 1.62 9.09 3 08.12.2014,09:19 09.12.2014,10:00 0.3 3.63 10.3 4 05.01.2015,10:38 06.01.2015,10:39 0.48 0.71 6.08 5 02.02.2015,09:28 03.02.20150,9:40 0.34 3.3 1.1 6 04.03.2015,08:25 05.03.2015,08:35 0.84 1.9 3.36 7 13.04.2015,10:30 14.04.2015,10:30 0.9 2.13 9.37 8 04.05.2015,09:10 05.05.2015,09:48 0.76 0.83 1.48 9 16.06.2015,08:58 17.06.2015,09:05 0.8 0.88 1.03 10 22.07.2015,09:04 23.07.2015,10:18 0.59 0.36 0.9 11 10.08.2015,09:45 11.08.2015,09:50 0.74 0.77 1.97 12 23.09.2015,09:27 24.09.2015,10:24 0.52 1.58 2.61 13 19.10.2015,10:08 20.10.2015,10:23 0.69 2.43 7.56 14 02.11.2015,16:07 03.11.2015,16:46 0.61 2.63 4.91 15 16.12.2015,10:51 17.12.2015,14:57 0.72 2.79 7.83 16 19.01.2016,10:39 20.01.2016,11:19 1.19 3.12 8.41 17 16.02.2016,10:32 17.02.2016,10:45 0.43 1.26 8.5 18 01.03.2016,10:05 02.03.2016,16:07 1.16 1.67 8.98 19 06.04.2016,14:50 07.04.2016,15:07 0.34 0.92 4.66 20 03.05.2016,10:13 04.05.2016,10:35 0.24 2.47 3.47 21 27.06.2016,09:50 28.06.2016,10:11 0.19 0.23 0.84 22 18.07.2016,08:40 19.07.2016,08:52 0.31 0.34 2.47 23 08.08.2016,11:35 09.08.2016,11:12 0.8 0.83 1.1 24 18.09.2016,16:00 19.09.2016,16:20 0.67 1.28 3.55 25 09.10.2016,09:01 10.10.2016,08:56 0.87 1.71 3.52 26 14.11.2016,11:10 15.11.2016,11:35 0.18 0.61 0.78 27 07.12.2016,10:42 08.12.2016,10:32 1 1.62 9.66 28 03.01.2017,11:50 04.01.2017,12:05 0.869 2.309 5.76 29 13.02.2017,10:38 13.02.2017,10:38 0.515 1.412 6.55 30 02.03.2017,15:52 03.03.2017,15:08 1.679 2.622 7.69 31 17.04.2017,10:56 18.04.2017,11:24 0.393 0.854 1.21 32 03.05.2017,17:15 04.05.2017,17:22 0.223 1.129 2.14 33 20.06.2017,11:00 21.06.2017,09:45 0.625 0.669 0.484 34 20.07.2017,09:45 21.07.2017,09:15 0.227 0.238 0.765 35 07.08.2017,11:25 08.08.2017,11:16 0.517 0.372 0.743 36 29.09.2017,16:35 30.09.2017,17:15 0.235 0.265 0.387 37 30.10.2017,09:00 31.10.2017,17:05 0.905 1.314 0.781 38 17.11.2017,16:10 19.11.2017,11:50 0.172 0.298 0.649 39 09.12.2017,20:12 10.12.2017,19:33 0.538 2.054 0.646 *The local time of Nanning is given in the following format: DDMMYY, HH:MM (day, month, year, hour, minute; 08.12.2014 is read as 8 December 2014) In this work, we show that air movement in the polar strato- mechanism driving air movement variations in the sphere affects the tropical troposphere based on observations stratosphere-troposphere coupling system. We adopt Be as of radioactive materials near the ground in the tropics. These a tracer for the stratosphere and Pb as a tracer for the tro- chemical observations further strengthen the dynamic aspects posphere. With this framework, this work addresses the fol- of stratosphere-troposphere coupling processes (Hoskins et al. lowing issues. (1) A significant correlation has been observed 1985). In this paper, we consider the AO as the main between Be and AOI, proving that the impact of the AO from Korean Meteorological Society X. Chen et al. the NH polar stratosphere can be observed near the surface of system containing a model BE3830 detector (CANBERRA) the tropical troposphere. (2) The good linear correlations be- with a crystal size of Φ 80 mm × 30 mm. The counting error 7 210 tween Be and Pb indicate that the stratosphere and tropo- for radioactivity measurements was approximately 10% at the sphere are coupled. 1 sigma level (Lee et al. 2004). The linear energy scale of the analyzer was calibrated with photon peaks from a Co-60 source (1332 keV) with the full width at half maximum (FWHM) of energy no higher than 1.80 keV and with a 2 Data and Methods 50.9% relative efficiency. The measurement time was longer than 86,400 s, and the minimum detection limits for Be, 2.1 Observational Data 210 210 3 Pb, and Po were 0.017–0.022 mBq/m ,0.01–0.03 3 3 mBq/m and 0.001–0.005 mBq/m , respectively. The uncer- 2.1.1 Site Description 210 7 tainties of Pb and Be activities were controlled to below 5%, and the uncertainties of Po were approximately 13%. The sampling site is an automatic environmental station in 7 210 In this paper, the Be and Pb activities were determined Nanning city, China (22.8°N, 108.5°E). Nanning has a humid with γ rays of 477.6 keV (Pγ = 10.43%) and 46.5 keV (Pγ = subtropical monsoon climate with an average temperature of 4.05%), respectively. The detection efficiency was obtained 21.7 °C and abundant rainfall (Deng et al. 2018). The average with laboratory source calibration software (LabSOCS). annual rainfall is 1298 mm, and Nanning has a humid summer LabSOCS was considered reliable for gamma ray detector and a slightly dry winter with distinctive dry and wet seasons efficiency calibrations, and the deviation of detection efficien- (which result from the impact of the Asian monsoon). cy calculated by this method was less than 10% (Bronson 2003;Liand Geng, 2010;Done et al. 2016). The γ energy 2.1.2 Sample Collection spectrum data were analyzed with Genie-2000 spectrum anal- ysis software to obtain the activities and uncertainties of Pb Aerosol samples are collected with a PM-800 large-flow aero- 7 3 and Be in the aerosol samples (mBq/m ) (Rastogi and Sarin sol sampler with a mounted HB1 polypropylene fiber filter 2008; Baskaran and Shaw 2001;Leppänenetal. 2010; membrane and an electric tablet press (Fig. 1). The collection Dueñas et al. 2011;Duet al. 2020). efficiency of the HB1 filter membrane for 0.5 μm aerosol After gamma spectrometry analysis, each sample was particles is approximately 99%. The operational flow of the 3 spiked with Po as a tracer, and the polonium in the sample sampler is set to 600 m /h to ensure that the standard- 3 was then dissolved with concentrated nitric acid. The residue condition volume of sampling is not smaller than 10,000 m . was dissolved/leached with hydrochloric acid, and ascorbic After sampling, the volume of air and the start and end times acid was added thereafter. In the hydrochloric acid system, are recorded. The sampling frequency is one sample over ap- polonium was self-plated onto a silver disc and determined proximately 24 h every month from October 2014 to with an alpha spectrometry (Canberra, 7200–4 PIPS) instru- December 2017. The total number of samples is 39. Each ment connected to an Alpha Analyst to calculate the activity aerosol sample is compressed into a cylinder with a diameter of Po (Carvalho 1995; Huh and Su 1999; Baskaran and of 70 mm and a length of 10 mm (Bourcier et al. 2011; Zhang Shaw 2001; Daish et al. 2005;Matthews et al. 2007). et al. 2015). 2.1.3 Sample Analysis 2.2 The HYSPLIT Model After encapsulation, the radioactivity was measured with a In this work, we apply the National Oceanic and Atmospheric high-purity germanium gamma (HPGe-γ) spectrometer Administration (NOAA) HYSPLIT model (Stein et al. 2016) Fig. 1 a The aerosol collector is installed in the integrated automatic monitoring station, and the sampling port is approximately 2 m from ground level; b theinsideofthe aerosol collector where the filter membrane is placed; c the filter membrane, where the black areas are aerosols Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... to produce back trajectories in the filtering sampling periods To rank the effects of the above parameters on the surface- with a duration of 168 h (7 days). Back trajectories are calcu- observed X, we apply a linear regression model to compute the lated every six hours over a specific sampling period. The statistical correlations between both the observed X and vari- source site is located in Nanning (latitude: 22.8°N; longitude: ables and among the variables (Wang and Chau 2013). The 108.5°E), and the height is 100 m above ground level because correlations between two variables are measured by the cal- the air below 100 m can be regarded as a uniform mixing culated correlation coefficient R. The statistical significance of layer. The vertical motion calculation method relies on a ver- a correlation is tested by computing Student’s t test probability tical velocity model, for which we use the meteorology over P(Press et al. 1992). the sampling period from the National Centers for Environmental Prediction (NCEP) GDAS0p5 (Global Data 2.4 The US EML Global Air Sampling Data Assimilation System 0.5 degrees longitude-latitude). Since the number of samples is 39 and the duration of each sampling The US EML has a network of air sampling sites that measure 7 210 period is longer than 20 h, there are a total of 144 back Be, Pb, and other nuclides on a global scale (Larsen et al. trajectories. 1995). The global coverage of EML surface sites is excellent for comparing and testing the results obtained from the analysis of local measurements performed in Nanning. It is important to test 2.3 Linear Regression Search whether the results obtained from Nanning are specific only to Nanning or whether they are general features on a global scale. In For a surface-observed variable X, we can define X = X(φ, λ, h, this context, the EML data serve as a testbed for verifying the H, P, A, C). Here, φ, λ, h and H are determined from the results obtained from the Nanning data. HYSPLIT back trajectories, φ indicates the maximum and min- imum latitudes, λ gives the maximum and minimum longitudes, h represents the maximum and minimum altitudes, H is the 3 Results mixing depth of the planetary boundary layer, and P is the 24- h precipitation rate obtained from the United Kingdom 3.1 Time-Series Measurements Meteorological Office (UKMO) Hadley Centre. The data ana- 7 210 210 lyzed in this work are HadISD version 3.1.0.201911p (Dunn Time-series measurements of Be, Pb, and Po over et al. 2012, 2014, 2016). A is the AOI, which is the daily mean 39 months from 2014 to 2017 are shown in Fig. 2(a).The 7 3 data obtained from the National Centers for Environmental average specific activity of Be is 4.21 mBq/m and is in the Prediction (NCEP)/National Center for Atmospheric Research range of 0.39–12.70 mBq/m . The average specific activity of 210 3 (NCAR) reanalysis (Zhou et al. 2001), and C indicates the Pb is 1.51 mBq/m and is in the range of 0.23–3.92 mBq/ 3 210 3 ground-level cosmic ray observations obtained from the cosmic m . The average specific activity of Po is 0.61 mBq/m and 3 7 ray station of the Sodankyla Geophysical Observatory, is in the range of 0.17–1.68 mBq/m . The activity level of Be University of Oulu, Finland (Mishev et al. 2014). is higher than the global average level of 2.45 mBq/m3 based The daily AO index is obtained from the National Oceanic on long-term observations of more than 70 stations around the and Atmospheric Administration (NOAA) Climate Prediction world (Koch et al. 1996). The activity of Be is comparable to Center (ftp://ftp.cpc.ncep.noaa.gov/cwlinks/norm.daily.ao. that determined at other observation stations (EML data, as 210 210 index.b500101.current.ascii). The daily AO index is shown in Fig. 5). The activities of Pb and Po in the calculated via methods similar to Thompson and Wallace ambient aerosols mostly exceed the simulated values at 0.5 (2000) and Thompson et al. (2000). The daily AO index is and 0.05 mBq/m , respectively (UNSCEAR 2000). However, 210 210 determined by projecting the daily 1000 hPa height anomalies the activity levels of Pb and Po at Nanning are compa- at latitudes north of 20°N onto the leading empirical orthogo- rable to those over other cities in China (Pan et al. 2017). The nal function (EOF) (https://www.cpc.ncep.noaa.gov/products/ three nuclides exhibit a seasonal variation pattern: higher ac- precip/CWlink/daily_ao_index/ao.shtml). The monthly mean tivity in winter and lower activity in summer. The overall 7 210 210 1000 hPa height anomalies north of 20°N are used to construct concentration of Be is higher than that of Pb and Po, the EOF. The daily AO index is normalized by the standard and its fluctuation is also more notable. Rainfall is the main deviation of the monthly index (based on the 1979–2000 pe- process of aerosol removal from the atmosphere. Rainfall is riod). NCEP/NCAR reanalysis data at 2.5 degree longitude- abundant in the summertime in Nanning, which decreases 210 210 7 latitude resolution are used in the construction of the monthly Pb and Po, similar to Be. Although the production rate EOF (https://www.cpc.ncep.noaa.gov/products/precip/ of Be at any given latitude in the atmosphere does not change CWlink/daily_ao_index/history/method.shtml). The positive with the season, the seasonal intrusion of lower stratospheric AO index corresponds to negative height anomalies over the air and washout of atmospheric aerosols carrying Be leads to polar region, and vice versa (Thompson et al. 2000). the enrichment of Be during late winter and early spring, Korean Meteorological Society X. Chen et al. 210 210 (a) The activities of Pb and its progeny Po exhibit sea- sonal variation, with low concentrations in summer and high concentrations in winter. The back trajectory maps of Pb and Po are shown in Fig. 2(b). The back trajectories of the higher concentrations are overwhelmingly distributed over the land area. Oceanic air masses from the South China Sea play a dominant role in affecting the weather in Nanning in summer with negligible Rn activity, while the back trajectories of the land air masses in winter indicate higher Rn activity. 222 210 210 Therefore, the activity of the Rn, Pb and Po progenies exhibits the same seasonal distribution in aerosols (Carvalho 1995;Dueñas etal. 2011). 3.2 Correlation Analysis Figure 3(a) shows that the correlation between Be and the AOI is the most significant, with an R = 0.26, and the P value is 0.0268, followed by Pb, with an R = 0.20 and a P value of 0.0826. The correlation between Po and the AO is an R value of 0.29 and a P value of 0.0138. More noteworthy dis- (b) cussions are presented below. As a tracer of the STE, the 7 210 correlation of Be versus Pb is significant, with R = 0.62 and a P value <0.01 (Fig. 3(c)). Precipitation is negatively correlated with the Be concentration, with R = 0.30 and a P value = 0.11 (Fig. 3(b)). Note that Fig. 3(a) also shows that 7 2 low levels of Be (less than 1 mBq/m ) are also associated with a high AOI, indicating the involvement of multiple pro- Nanning 7 210 210 Be Pb Po cesses in the scatter diagram. 7 210 7 Fig. 2 a Time series of the activity of the three nuclides ( Be, Pb, and Figure 3(b) shows negative correlations between Be, Po), the AOI, earthquake events, cosmic rays, and precipitation in Pb and precipitation. The negative correlation between Nanning from 9/10/2014 to 10/12/2017; b trajectory map for (i) Be: 3 3 Pb and precipitation is characterized by R = 0.35 and a P green (0–3.0 mBq/m ), blue (3.0–6.0 mBq/m ), and red (6.0–9.0 mBq/ 3 210 3 3 value of 0.06, while Po shows no clear correlation with m ); (ii) Pb: green (0–1.0 mBq/m ), blue (1.0–2.0 mBq/m ), and red 3 210 3 210 (2.0–3.0 mBq/m ); (iii) Po: green (0–0.5 mBq/m ), blue (0.5–1.0 mBq/ precipitation. An earthquake is the source event for Pb 3 3 m ), and red (1.0–1.5 mBq/m ). The Nanning monitoring site is and Po. Due to crustal rupture, a high concentration of highlighted by bold white stars and arrows and is indicated in the central Rn can diffuse from crustal soil to the atmosphere. figure Therefore, seismic events may be able to explain the short- 210 210 term and sudden high-activity events of Pb and Po as which does not occur in summer (Marenco and Fontan 1974; long half-life progenies of Rn. However, seismic signals Feely et al. 1989;Du et al. 2020). are relatively complex and are not explained in this work. 7 7 Be is a cosmogenic radionuclide that is mainly produced To clarify the effect of the AO on Be, we perform a series in the stratosphere. Due to cosmic rays, Be is continuously of sensitivity tests with various durations (from 2 to 7 days) of produced. Ground-level cosmic ray observations revealed a the back trajectories. The test results reveal that the 6–7day persistent increasing trend from October 2014 to December back trajectories result in the most significant correlation (R = 7 7 2017. Despite increasing cosmic rays, the activity of Be in the 0.46 and P value <0.01) between Be and height. Hence, near-surface air did not persistently increase. Hence, the var- correlation analysis is performed on these four variables 7 7 iations in ground-level Be concentrations are more associated (AOI, Be, latitude, and altitude) by considering three AOI with AO patterns than with changes in the incoming cosmic cases (all, positive phase, and negative phase (see Fig. 4)). rays. The back trajectory analysis (Fig. 2(b)) clearly shows For data reliability, a comparison between the EML and that almost all of the higher concentrations of Be originate Nanning observation data is conducted via scatter plot analy- 7 210 7 from middle and high latitudes. Some of the trajectories start sis of Be versus AOI and of Pb versus Be. in polar regions. These back trajectories indicate that Be ob- Figure 4(a) shows that 63% (90/142) of the back trajecto- served near the ground in Nanning was affected by air from ries in the case of AOI > 0 originate in the NH polar region and middle and high northern latitudes mid-latitude regions. The back trajectories for AOI < 0 (37%) Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... 210 210 Fig. 3 Scatter plots of the observed variables versus the AOI. a The three Pb (central panel), and Po (right panel)) versus precipitation. c 7 210 210 210 7 210 radionuclides ( Be (left panel), Pb (central panel), and Po (right Correlations between Pb and Be (left panel) and between Po and 7 7 panel)) versus the AOI. b The three radionuclides ( Be (left panel), Be (right panel) are confined to latitudes south of 50°N. Both Be and the AOI panel). The correlation coefficient R increased to R = 0.48 in exhibit a significant correlation with the maximum altitudes the case of AOI > 0 (P value <0.01; Fig. 4(b),middle panel). and latitudes of the HYSPLIT back trajectories (Fig. 4(b, c, d, In terms of the AOI versus altitude, the R = 0.10 in the case of e)). Especially in the case of AO > 0, all the correlations are all AOI data (Fig. 4(c), left panel). The correlation coefficient more notable. Regarding the AOI versus latitude, the R = 0.28 R increased to R = 0.32 in the case of AO > 0 (P value<0.01; in the case of all AOI data (P value <0.01; Fig. 4(b), left Fig. 4(c),middle panel). Korean Meteorological Society X. Chen et al. Fig. 4 Scatter plots of Be measurements versus the highest altitudes and latitude. c All AOIs (left panel), positive AOIs (central panel), and latitudes of the air mass back trajectories from HYSPLIT. a Spatial negative AOIs (right panel) versus altitude. d Altitude versus Be for all distribution of the back trajectories: all AOIs (left panel), positive AOIs AOIs (left panel), positive AOIs (central panel), and negative AOIs (right (middle panel), and negative AOIs (right panel). b All AOIs (left panel), panel). e Latitude versus Be (left panel) and altitude versus latitude (right positive AOIs (central panel), and negative AOIs (right panel) versus panel) for positive AOIs The correlation between altitude and Be is significant, (P value <0.01; Fig. 4(d), middle panel). These results prove with R = 0.40 in the case of all AOI data (Fig. 4(d),leftpanel). that the sources of the elevated Be are located at high alti- The correlation coefficient is R = 0.37 in the case of AOI > 0 tudes. The correlations between latitude and Be (R = 0.56 in Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... Fig. 4 (continued). the case of AOI > 0, with a P value <0.01; Fig. 4(e),left panel) well as from the high to low latitudes. These processes explain 7 7 prove that elevated Be is associated with higher latitudes in why the AOI exhibits good correlations with Be. These four the NH. The latitude versus altitude correlations (R = 0.61, aspects ( Be, AOI, latitude, and altitude) are notably correlat- with a P value <0.01; Fig. 4(e), right panel) demonstrate that ed through analysis of the back trajectories. the high-latitude air masses originated from the NH high In summary, Fig. 4 demonstrates that elevated Be is asso- latitudes. ciated with air coming from high latitudes (polar regions) and The polar stratosphere exhibits the highest Be production high altitudes (lower stratosphere). In the case of AOI > 0, rate, while the tropical lower troposphere experiences the low- strong and positive regression correlations exist between lati- 7 7 est Be production rate (Feely et al. 1989). The variations in tude and altitude versus Be and between altitude versus lati- the AO exhibit chains of coupled flow pattern changes from tude. In the case of AOI < 0, a weak positive regression is the polar stratosphere downward toward the lower-latitude observed. All correlation coefficients are statistically signifi- troposphere. With the AO as a key mechanism, air parcels cant (P value<0.01 for positive phases of the AO). These move from higher latitudes and altitudes (the polar strato- results indicate that the air masses enriched in Be originate sphere that is rich in Be) to lower latitudes and altitudes from polar regions and the lower stratosphere. The distur- (the tropical troposphere) when the AO is positive, and East bance and variability of the polar vortex, exhibited as the Asia experiences a more notable STE. Therefore, it is easy to AOI, are the main causes of the elevated Be observed at the understand that with the higher altitudes and latitudes of the tropical Nanning site. HYSPLIT trajectories, it is more likely for the air enriched in The back-trajectory computation strongly supports our Be to be transported from the stratosphere to troposphere, as findings of the dominant role of the AO in controlling the Korean Meteorological Society X. Chen et al. Fig. 5 Scatter plots of EML data versus Nanning data. a At 7 210 Barrow, Be versus Pb, and (b) AOI versus Be. Panels (c)and (d)are thesameas (a) and (b)but for Montgomery, Alabama. Red crosses represent Nanning data, and red straight lines are linear regression model results. Blue crosses represent EML data, and blue straight lines are linear regression model results 7 7 abundance of Be (Fig. 3(a)) and the significant correlation In Perth (32°S), Australia, Be is correlated with the AOI 7 210 210 7 between Be and Pb (Fig. 3(c)). Moreover, based on the with an R = 0.11, and Pb is correlated with Be with an R = meteorology along the back trajectories, we perform further 0.36 (P < 0.01). In Tasmania (40.73°S), Australia, the Be correlation analyses (Fig. 4) and prove that the air masses versus AOI correlation has an R-value of 0.11, and the Pb 7 7 enriched in Be originate from the polar regions and the lower versus Be correlation has an R-value of 0.21 (p <0.01). On 210 7 stratosphere. Reunion Island (21.10°S), the Pb versus Be correlation has an R-value of 0.36 (P < 0.01). The comparisons show that similar latitudes exhibit similar ranges of Be concentrations 3.3 Comparisons with EML Data and correlation coefficients between 210Pb and Be (R = 0.31, P < 0.01), while the Pb correlation coefficient range is half For data reliability and to test our results, scatter plot of that at the Nanning site (due to abundant fossil fuel burn- 7 210 7 analysis of Be versus AOI and Pb versus Be was ing). The patterns from the 5 Australian sites are consistent, again performed on the EML data, which contains more which verifies that they are correct. than 6000 observations on a global scale. Figure 5 shows In the NH, many sites exhibit a very good linear correlation 210 7 the sites in the NH that have similar patterns as Nanning. between Pb and Be and are geographically associated with Figures 6 and 7 show the sites in the Southern large mountain ranges in the NH, such as the Himalayas, Alps, Hemisphere (SH) that exhibit both positive correlations and Rocky Mountains (Fig. 8(a)). The downwind areas of 7 7 210 between the AOI and Be and between Be and Pb. high mountains easily experience vertical air oscillations, thus The correlation analysis results are statistically significant. intensifying the instability of tropospheric air and increasing Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... Fig. 6 The same as Fig. 5, but for sites in the SH. Panels (a) and (b) are for Reunion Island. Panels (c) and (d) are for Norfolk, Australia. Panels (e) and (f) are for Perth, Australia 7 210 advection and the disturbance between the troposphere and between Be and Pb indicates that the disturbance of the stratosphere. As a tracer of the STE, the good coherence air due to high mountains can promote the coupling of the Korean Meteorological Society X. Chen et al. Fig. 7 The same as Fig. 6, but for sites in the SH. Panels (a) and (b) are for Tasmania, Australia. Panels (c) and (d) are for Chatham, New Zealand. Panels (e)and (f) are for Mawson, Antarctica stratosphere and troposphere. Interestingly, Nanning exhibit- that were higher than those at all the EML sites. Nanning is 7 210 7 ed correlations of both Be versus AOI and Pb versus Be located in the westerly disturbance area on the leeward side of Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... Fig. 8 Spatial distribution of EML sites with statistically significant correlations for the analyzed pairs: (a) Be versus 210 7 Pb and (b) AOI versus Be 7 7 210 the Himalayas, which is the highest mountain range on Earth. paired AOI versus Be and Be versus Pb represent the Hawaii, affected by the Himalayas, is downwind of Nanning. AO-initialized stratosphere-troposphere coupled effect. Montgomery, Alabama, is on the east coast of the US and experiences a relatively severe air disturbance due to the Rocky Mountains. In Barrow, Alaska, which is affected by 4 Discussion and Conclusions the Alaska Mountain Range, the correlations between Pb 7 7 and Be are also notable with R = 0.59 and a P value <0.01, In this work, we showed that the ground levels of Be and 210 210 and the lower Pb activity may be due to its coastal location. Pb at the Nanning and EML stations in Alaska (Barrow), The Montgomery site (32°N) in Alabama exhibits a good Montgomery (Alabama), Australia (Perth, Tasmania, and 210 7 correlation between Pb and Be, with R = 0.49 (P <0.01). Norfolk), New Zealand (Chatham), and American Samoa Figure 8(b) shows the sites that exhibit statistical signifi- were positively and statistically significantly correlated with 7 210 cance in the linear regression analysis of Be versus Pb. an increase in the positive AOI. What are the mechanisms 7 210 This figure shows the sites that are the most responsive and resulting in the surface Be and Pb being positively corre- reflect the highest degree of coupling between the stratosphere lated with the AOI? What processes that lead to Be were and troposphere during the positive phases of the AO. positively correlated with Pb at these sites? 7 7 At these sites, the correlations between Be and AOI and The production rates of Be are higher in the upper tropo- 210 7 7 −1 between Pb and Be are significant with P-values that are sphere and lower stratosphere (25–50 Be atoms s (gram of −1 7 −1 less than 0.05; these sites include Barrow, Alaska and air) ) than in the lower troposphere (1–5 Be atoms s (gram −1 Montgomery, Alabama in the USA, and Perth and Tasmania of air) ;Koch etal. 1996). Approximately two-thirds of the 7 7 in Australia. Note that Fig. 7(e) shows that both Nanning and Be is produced in the stratosphere, and one-third of the Be is Mawson Station in Antarctica have similar measurements of produced in the troposphere (Rehfeld and Heimann 1995). On 7 210 210 Be, but the Pb at Mawson is very low compared with that the other hand, Pb is produced from the radioactive decay 210 222 at Nanning. The higher Pb activity at the Nanning site is of Rn, which is released from terrestrial soil (Koch et al. mainly due to its location in an inland city as well as industrial 1996). Hence, only a small contribution of stratospheric air is influence. Mawson Station in Antarctica, which is far from needed to produce a large change in the observed Be in sur- continents, has very low Pb activity due to the reduction face air (Dutkiewicz and Husain, 1985). (decay and diffusion) in Pb during long-distance ground Figure 9 shows the difference in geopotential height (m) at dust transport from remote terrestrial areas. On the other hand, 850 hPa between years of positive AO (1989, 1990, 1992, the elevated Be over Mawson, Antarctica indicates the abun- 1993, 1997, and 2000) and years of negative AO (1980, dant sources of Be from the lower stratosphere over 1985, 1987, and 2001) calculated by Lamarque and Hess Antarctica. (2004). The positive geopotential anomalies are associated 7 210 The good correlations between Be and Pb represent the with the positive anomalies of high pressures and clockwise spatial distribution of observations dominated by stratosphere- circulations. Red curves encircle the regions of the anomalous troposphere coupled effects (Fig. 8(b)). The good correlations highs with high pressure centers highlighted by H ,H ,H , 1 2 3 between the AOI and Be represent the spatial distribution of and H .H is centered at approximately 120°E and 45°N 4 1 sites with the AO-initiated stratospheric effect in the tropo- (eastern Asian continent). H is centered around the North sphere (Fig. 8(a)). The combined good correlations of the Pacific, at 150°W and 60°N. The high-pressure systems are Korean Meteorological Society X. Chen et al. STE and downward transport of elevated potential vorticity (PV) and Be to the lower troposphere (Black 2002;James et al. 2003). The Nanning site is located downstream of the H high- pressure system, while the H high-pressure system influences the Barrow site in Alaska during the positive AO phases. The rest of the sites (Mauna Loa, three sites in Australia, two sites in New Zealand, and American Samoa) are located in regions with enhanced subsidence during the positive AO phases (Limpasuvan et al. 2005; Zhao and Miller 2005). The HYSPLIT model calculations show that the back tra- jectories tend to originate in the high altitudes of the tropo- sphere and with the origins of the trajectories in northern higher latitudes. These results are presented in the regression model analysis (altitudes are correlated with latitudes). The clockwise back trajectories are consistent with the subsidence of the flows associated with the high-pressure systems from northern high latitudes and high altitudes to the tropical Nanning site. Fig. 9 A schematic diagram showing the distribution of the anomalous We used NCEP reanalysis data to check the sensitivity of high- and low-pressure systems associated with differences between the the HYSPLIT results with respect to the meteorological data positive and negative AO years. The shaded colors indicate the distribu- tion of the anomalous high (red) and low (blue) pressure systems adapted used in this work. Fig. S2 compares the horizontal distribution from Lamarque and Hess (2004). The locations of the high-pressure sys- of the back trajectories calculated with the GDAS0p5 data tems are indicated by H ,H ,H ,and H . Schematic flow symbols indi- 1 2 3 4 (Fig. S2(a)) and with the NCEP reanalysis data (Fig. S2(b)). cate that the main low-pressure system, L, over the Arctic regions is We note that the GDAS0p5 data have a horizontal resolution added to demonstrate the flow patterns associated with the anomalous high- and low-pressure systems. The bottom panel shows a meridional of 0.5 degrees longitude-latitude and contain output data col- vertical circulation through the 120°E and 60°W cross-sections (indicated lected every 3 h on 55 hybrid sigma-pressure levels from the by the green line in the upper panel) associated with the anomalous high- surface to 13 hPa. The reanalysis data have a horizontal reso- and low-pressure systems lution of a 2.5 degree longitude-latitude grid, output data col- lected every 6 h, and 17 pressure levels (1000, 925, 850, 700, accompanied by subsidence flow from the upper troposphere 600, 500, 400, 300, 250, 200, 150, 100, 70, 50, 30, 20, and to the lower stratosphere. The lower panel of Fig. 9 shows 10 hPa). Fig. S2 shows that the general patterns of the gridded vertical circulations associated with the anomalous high- and distribution of the occurrence of back trajectories are similar. low-pressure systems. Hence, high-pressure systems are asso- However, the results calculated with GDAS0p5 data show a ciated with enhanced subsidence (Lee et al. 2004). They are more widespread distribution of the back trajectories than the conducive to the vertical transport of elevated Be from the results calculated with the reanalysis data. The GDAS0p5 data upper troposphere and lower stratosphere (UTLS) regions to have a higher horizontal and vertical resolution than the re- the lower troposphere. The subsidence associated with high- analysis data, resulting in a better representation of the vertical pressure systems also suppresses convection and precipitation velocity. The linear regression analysis of the AOI and Be processes in the atmospheric boundary layer, leading to the versus latitudes and altitudes calculated with the reanalysis enhancement of Pb at the surface (Rehfeld and Heimann data are consistent with the results calculated with the 1995;Koch etal. 1996;Wang et al. 1999). Hence, the devel- GDAS0p5 data. Elevated AOIs are associated with air origi- opment of the positive AOI is conducive to the transport of nating from northern higher latitudes (Fig. S3(a)). Elevated 7 7 elevated Be from the UTLS regions to the lower troposphere. Be is associated with air originating from northern higher The negative differences in the AOI are associated with the latitudes (Fig. S3(b)). The air from northern higher latitudes negative anomalies of the low pressure and anti-clockwise originates from elevated altitudes (Fig. S3(c)). Elevated AOIs circulations. They are associated with enhanced upward mo- are associated with air from higher altitudes (Fig. S3(d)). tion. The development of the anomalous low-pressure system, Elevated Be concentrations are associated with air originat- L, over the Arctic region acts to enhance the strength of the ing from higher altitudes (Fig. S3(e)). The altitudinal origins polar vortex (Thompson and Wallace 1998;Baldwin and of the air calculated with the reanalysis data are mostly limited Dunkerton 1999; Ambaum and Hoskins 2002). A developing to altitudes below 5 km (Fig. S3(d)), which are lower than the polar vortex produces atmospheric circulations similar to origins of the air calculated with the GDAS0p5 data (Fig. those of the AO patterns in Fig. 9 and is conducive for the 4(d)). These comparisons indicate that the vertical velocities Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... calculated from the coarse resolution of the reanalysis data are (Fig. S5(a)), and decreases in H O(Fig. S5(b)) and tempera- lower than the high resolution of the GDAS0p5 data. A sep- ture (Fig. S5(c)) occur in the troposphere. At Hong Kong, O arate study has evaluated the quality of the GDAS0p5 data for increases at altitudes below 7 km (Fig. S5(d)), and decreases back trajectory studies over East Asia. The calculations show in H O (Fig. S5(e)) and temperature (Fig. S5(f)) occur in the that elevated CO concentrations over North Pacific flight cor- troposphere. Hong Kong is located 580 km east of the ridors can be traced back to the ground level industrial areas Nanning site. Hong Kong has ozonesonde data that is closest over East Asia. In contrast, the back trajectories show that low to the Nanning site. In the middle of the North Pacific Hilo CO in the upper troposphere is associated only with the air in site, O increases at altitudes below 4 km and above 6 km in the upper troposphere, where the CO concentrations are low. the troposphere (Fig. S5(g)), H O decreases at altitudes below We note that Nanning has abundant precipitation leading to 2 km (Fig. S5(h)), and temperature decreases throughout the wet summers, and rainfall is the main removal process of troposphere (Fig. S5(i)). aerosols from the atmosphere. Therefore, the influence of re- We also used ozonesonde data from Hong Kong to test the moval of rainfall on radionuclides in aerosols should be taken sensitivity of the regression results when seasonal cycles were into account. Therefore, in Fig. 3(b), we considered the corre- excluded. The Be data cover 4 winters (2014, 2015, 2016, lation analysis of rainfall on the activity of the three nuclides. and 2017), while the ozonesonde data in Hong Kong cover a The negative correlations shown in Fig. 3(b) are consistent period of 20 years (2000–2020) and have 20 winters for anal- with previous works (e.g., Rehfeld and Heimann 1995; ysis. Fig. S5(d), (e), and (f) demonstrate that the profiles of O Koch et al. 1996), showing the wet scavenging effect of Be and H O trends and the increases in the AO over Hong Kong and Pb in Nanning. are consistent with the trends of 7Be that vary with AO over The dynamics of recent climate change have been linked to Nanning during the analysis period (December 2014– the Arctic (e.g., James et al. 2003). The North Atlantic December 2017). Analysis of the 20 years of data shows that Oscillation (NAO) and AO have become more positively biased O increased as the AO increased at altitudes below 7 km (Fig. since 1950 (e.g., Visbeck et al. 2001;Hurrell et al. 2004). As S6(a)), H O decreased as the AO increased at altitudes below 7 210 shown in this study, the levels of near-surface Be and Pb are 7km (Fig. S6(b)), and temperature decreased as the AO in- positively correlated with the increasing trends in the positive creased throughout the troposphere (Fig. S6(c)). When data 7 210 AO. Continuous measurements of near-surface Be and Pb only from the winter months (December, January, and can provide radioactive evidence for monitoring continuous February) are considered in the analysis, the results show that changes in the AO and the links to global warming. increases in O occur with increases in the AO at altitudes Based on previous works (Wang et al. 2002;Wangand below 3 km (Fig. S6(d)), and decreases in H O occur with Kau 2015 and references therein; and references cited in the increases in the AO at altitudes below 3 km (Fig. S6(e)). manuscript), we use the association between ground-level ob- Hence, the results in the lower troposphere show that the O served Be (a stratospheric tracer) and the AOI to indicate the and H O changes with the increases in AO are consistent changes in the STE associated with the AOI in this work. The between all data and winter-only data. Fig. S6(f) shows that air with stratospheric origins contains elevated Be, elevated temperatures are slightly increased in the troposphere with O ,low CO,and lowH O. Hence, we also analyze O ,H O, increases in the AO. This result is consistent with a longer 3 2 3 2 and temperature from ozonesonde measurements (WOUDC trend of increases in tropospheric temperatures associated 2021). Fig. S4 shows the linear regression model analysis of with global warming. O ,H O, and temperature versus AOI at three sites over the 3 2 North Pacific from 2014 to 2017. At an altitude of 3 km (to reduce the impact of ground-level photochemical O produc- Supplementary Information The online version contains supplementary tion), increases in O are associated with increases in the AOI material available at https://doi.org/10.1007/s13143-021-00237-2. at Taipei (25.00°N, 121.44°E; Fig. S4(a)), Hong Kong (22.31°N, 114.17°E; Fig. S4(d)), and Hilo, Hawaii Acknowledgments We gratefully acknowledge the NOAA Air (19.43°N, 155.04°W; Fig. S4(g)). In contrast, decreases in Resources Laboratory (ARL) for providing the HYSPLIT transport and dispersion model and/or the READY website http://www.arl.noaa.gov/ H O are associated with increases in the AOI at Taipei (Fig. ready.html used in this publication; the United States (US) Environmental S4(b)) and Hong Kong (Fig. S4(e)). H Oat Hilo (Fig. S4(h)) Measurements Laboratory (EML) for the global observational data was compounded by H O evaporation from the underlying (https://www.wipp.energy.gov/NAMP/EMLLegacy/databases.htm); the ocean. Additionally, an increase in AOIs are associated with United Kingdom Meteorological Office (UKMO) Hadley Centre HadISD version 3.1.0.201911p for the precipitation data (https://www. decreases in temperature in Taipei (Fig. S4(c)), Hong Kong metoffice.gov.uk/hadobs/hadisd/v310_201911p/download.html); the (Fig. S4(f)), and Hilo (Fig. S4(i)). Fig. S5 shows regression cosmic ray station of the Sodankyla Geophysical Observatory, analysis profiles throughout the troposphere, from the surface University of Oulu, Finland, for the cosmic ray data (https://cosmicrays. to an altitude of 10 km, with respect to increases in the AOI. oulu.fi/); and the China Earthquake Networks Center for the earthquake data (https://www.cenc.ac.cn/). The EML sample archives make At Taipei, O increases at altitudes of 3 km and above 5 km Korean Meteorological Society X. Chen et al. available environmental radiological data collected for programs funded health effects, ACS Symposium Series, 331, pp. 377–397. through the U.S. Atomic Energy Commission, the U. S. Energy Research American Chemical Society, Washington, D.C. (1987) and Development Administration and the U. S. Department of Energy. Bourcier, L., Masson, O., Laj, P., Pichon, J.M., Paulat, P., Freney, E., All of these programs have been terminated. The databases were last Sellegri, K.: Comparative trends and seasonal variation of 7Be, updated in 1999. No additional data will be added to these databases. 210Pb and 137Cs at two altitude sites in the central part of France. Any inquiries about these programs should be made to webmaster@ J. Environ. Radioact. 102(3), 294–301 (2011) eml.st.dhs.gov. We greatly benefited from the sampling support and Bronson, F.L.: Validation of the accuracy of the LabSOCS software for data provided by the Radiation-Environment Management and mathematical efficiency calibration of Ge detectors for typical lab- Monitoring Station of the Guangxi Zhuang Autonomous Region, oratory samples. J. Radioanal. Nucl. Chem. 255(1), 137–141 (2003) Nanning 530222, China (http://nnsa.mee.gov.cn/zjjg/pcjg/201501/ Brost, R.A., Feichter, J., Heimann, M.: Three-dimensional modeling of t20150107_305223.html; https://sthjt.gxzf.gov.cn). The Nanning data the concentration and deposition of Pb aerosols. J. Geophys. Res. reported in this work are shown in Table 1. KYW was funded under 96, 22,423–22,445 (1991) 222 210 210 108-2111-M-008-034. Carvalho, F.P.: Origins and concentrations of Rn, Pb, Bi and Po in the surface air at Lisbon, Portugal, at the Atlantic edge of the European continental landmass. Atmos. Environ. 29(15), 1809– Open Access This article is licensed under a Creative Commons 1819 (1995) Attribution 4.0 International License, which permits use, sharing, adap- Chen, W., Lan, X.Q., Wang, L., Ma, Y.: The combined effects of the tation, distribution and reproduction in any medium or format, as long as ENSO and the Arctic oscillation on the winter climate anomalies in you give appropriate credit to the original author(s) and the source, pro- East Asia. Chin. Sci. Bull. 58(12), 1355–1362 (2013). https://doi. vide a link to the Creative Commons licence, and indicate if changes were org/10.1007/s11434-012-5654-5 made. The images or other third party material in this article are included Cristofanelli, P., Bonasoni, P., Tositti, L., Bonafé, U., Calzolari, F., in the article's Creative Commons licence, unless indicated otherwise in a Evangelisti, F., Sandrini, S., Stohl, A.: A 6-year analysis of strato- credit line to the material. If material is not included in the article's spheric intrusions and their influence on ozone at Mt. Cimone (2165 Creative Commons licence and your intended use is not permitted by m above sea level). J. Geophys. Res. 111, D03306 (2006). https:// statutory regulation or exceeds the permitted use, you will need to obtain doi.org/10.1029/2005JD006553 permission directly from the copyright holder. To view a copy of this Cristofanelli, P., Bonasoni, P., Carboni, G., Calzolari, F., Casarola, L., licence, visit http://creativecommons.org/licenses/by/4.0/. Zauli Sajani, S., Santaguida, R.: Anomalous high ozone concentra- tions recorded at a high mountain station in Italy in summer 2003. Atmos. Environ. 41,1383–1394 (2007) References Cristofanelli, P., Calzolari, F., Bonafé, U., Duchi, R., Marinoni, A., Roccato, F., Tositti, L., Bonasoni, P.: Stratospheric intrusion index (SI2) from baseline measurement data. Theor. Appl. Climatol. 97, Ambaum, M.H., Hoskins, B.J.: The NAO troposphere-stratosphere con- 317–325 (2009) nection. J. Clim. 15,1969–1978 (2002) Cutlip, K.: Northern influence. Weatherwise. 53(2), 10–11 (2000) Baldwin, M.P., Dunkerton, T.J.: Propagation of the Arctic oscillation Daish, S.R., Dale, A.A., Dale, C.J., May, R., Rowe, J.E.: The temporal from the stratosphere to the troposphere. J. Geophys. Res. 210 210 variations of 7Be, Pb and Po in air in England. J. Environ. 104(D24), 30,937–30,946 (1999) Radioact. 84(3), 457–467 (2005). https://doi.org/10.1016/j.jenvrad. Balkanski, Y.J., Jacob, D.J., Gardner, G.M., Graustein, W.C., Turekian, 2005.05.003 K.K.: Transport and residence times or tropospheric aerosols in- Deng, Q., Wei, Y., Zhao, Y., Han, X., Yin, J.: Understanding the natural ferred from a global three-dimensional simulation of Pb. J. and socioeconomic factors behind regional longevity in Guangxi, Geophys. Res. 98, 20573–20586 (1983) 210 210 210 China: Is the centenarian ratio a good enough indicator for assessing Baskaran, M.: Po and Pb as atmospheric tracers and global Pb the longevity phenomenon? Int. J. Environ. Res. Public Health. fallout: a review. J. Environ. Radioact. 102,500–513 (2011) 15(5), pii: E938 (2018). https://doi.org/10.3390/ijerph15050938 Baskaran, M., Shaw, G.E.: Residence time of arctic haze aerosols using 210 210 Dibb, J.E., Talbot, R.W., Gregory, G.L.: Beryllium 7 and lead 210 in the the concentrations and activity ratios of Po, Pb and 7Be. J. western hemisphere Arctic atmosphere: observations from three re- Aerosol Sci. 32(4), 443–452 (2001). https://doi.org/10.1016/ cent aircraft-based sampling pograms. J. Geophys. Res. 97(D15), S0021-8502(00)00093-8 16709 (1992). https://doi.org/10.1029/91jd01807 Bhandari, N., Lal, D.: Vertical structure of the troposphere as revealed by radioactive tracer studies. J. Geophys. Res. 75,2974–2980 (1970) Done, L., Tugulan, L.C., Gurau, D., Dragolici, F., Alexandru, C.: Black, R.X.: Stratospheric forcing of surface climate in the artic oscilla- Comparison of LabSOCS and GESPECOR codes used in gamma- tion. J. Clim. 15(1), 268–277 (2002) ray spectrometry. International Conference on Radionuclide Metrology & Its Applications. 109,539–543 (2016) Bonasoni, P., Evanegelisti, F., Boanfé, U., Feldmann, H., 7 210 Du, J., Baskaran, M., Du, J.: Atmospheric deposition of Be, Pb and Memmesheimer, M., Stohl, A., Tositti, L.: Stratosphere- Po during typhoons and thunderstorm in Shanghai, China and troposphere exchanges: case studies recorded at Mt. Cimone during global data synthesis. Sci. China Earth Sci. 63(4), 602–614 (2020). VOTALP project. Physics and Chemistry of the Earth, Parts C. https://doi.org/10.1007/s11430-019-9481-9 24(5), 443–446 (1999) Bonasoni, P., Evangelisti, F., Bonafé, U., Ravegnani, F., Calzolari, F., Dueñas, C., Orza, J.A.G., Cabello, M., Fernández, M.C., Cañete, S., Stohl, A., Tositti, L., Tubertini, O., Colombo, T.: Stratospheric Pérez, M., Gordo, E.: Air mass origin and its influence on radionu- 7 210 ozone intrusion episodes recorded at Mt. Cimone during VOTALP clide activities ( Be and Pb) in aerosol particles at a coastal site in project: case studies. Atmos. Environ. 34,1355–1365 (2000a) the western Mediterranean. Atmos. Res. 101(1–2), 205–214 (2011). Bonasoni, P., Stohl, A., Cristofanelli, P., Calzolari, F., Colombo, T., https://doi.org/10.1016/j.atmosres.2011.02.011 Evangelisti, F.: Background ozone variations at Mt Cimone station. Dunn, R. J. H., Willett, K.M., Thorne, P.W., Wooley, E.V., Durre, I., Atmos. Environ. 34,5183–5189 (2000b) Dai., A., et al. (2012). HadISD: a quality-controlled global synoptic Bondietti, E.A., Papastefanou, C., Rangarajan, C.: Aerodynamic size as- report database for selected variables at long-term stations from sociations of natural radioactivity with ambient aerosols. In: Hopke, 1973–2011, Clim. Past, 8, 1649–1679, https://doi.org/10.5194/cp- P.K. (ed.) Radon and is decay products: occurrence, properties and 8-1649-2012 Korean Meteorological Society Beryllium-7 and Lead-210 are Associated with an Increase in the Arctic Oscillation: Evidence from... Dunn, R.J.H., Willett, K.M., Morice, C.P., Parker, D.E.: Pairwise homo- model. J. Geophys. Res. Atmos. 101(13), 18651–18666 (1996). geneity assessment of HadISD. Clim. Past. 10,1501–1522 (2014). https://doi.org/10.1029/96jd01176 https://doi.org/10.5194/cp-10-1501-2014 Lal, D., & Peters, B. (1967). Cosmic ray produced radioactivity on the Dunn, R.J.H., Willett, K.M., Parker, D.E., Mitchell, L.: Expanding Earth. In: Sitte K. (Eds) Kosmische Strahlung II / Cosmic Rays II. HadISD: quality-controlled, sub-daily station data from 1931. Handbuch der Physik / Encyclopedia of Physics, Vol 9 / 46 / 2. Geoscientific Instrumentation Methods and Data Systems. 5,473– Springer, Berlin, Heidelberg 491 (2016). https://doi.org/10.5194/gi-5-473-2016 Lamarque, J.-F., Hess, P.G.: Arctic oscillation modulation of the northern Dutkiewicz, V. A., & Husain, L. (1985). Stratospheric and tropospheric hemisphere spring tropospheric ozone. Geophys. Res. Lett. 31(6), component of 7Be in surface air. J. Geophys. Res. 90,5783–5788. L06127 (2004). https://doi.org/10.1029/2003gl019116 Feely, H.W., Larsen, R.J., Sanderson, C.G.: Factors that cause seasonal Larsen, R.J., Sanderson, C.G., & Kada, J. (1995). EML surface air sam- variations in Beryllium-7 concentrations in surface air. J. Environ. pling program, 1990–1993 data. EML Report 572, 37–40, Radioact. 9(3), 223–249 (1989). https://doi.org/10.1016/0265- Environmental Measurements Laboratory, U.S. Department of 931X(89)90046-5 Energy, New York Gong, D.Y., Wang, S.W., Zhu, J.H.: East Asian winter monsoon and Lee, H.N., Wan, G., Zheng, X., Sanderson, C.G., Josse, B., Wang, et al.: 210 7 Arctic oscillation. Geophys. Res. Lett. 28,2073–2076 (2001) Measurements of Pb and Be in China and their analysis accom- 7 210 210 Graustein, W.C., Turekian, K.K.: Be and Pb indicate an upper tropo- panied with global model calculations of Pb. J. Geophys. Res. sphere source for elevated ozone in the summertime subtropical free 109, D22203 (2004). https://doi.org/10.1029/2004JD005061 troposphere of the eastern North Atlantic. Geophys. Res. Lett. 23, Lee, H.N., Tositti, L., Zheng, X., Bonasoni, P.: Analyses and compari- 7 210 7 210 539–542 (1996) sons of variations of Be, Pb, and Be/ Pb with ozone observa- tions at two global atmosphere watch stations from high mountains. Grossi, C., Ballester, J., Serrano, I., Galmarini, S., Camacho, A., Curcoll, J. Geophys. Res. 112, D05303 (2007). https://doi.org/10.1029/ R., Morguí, J.A., Rodò, X., Duch, M.A.: Influence of long-range 2006JD007421 atmospheric transport pathways and climate teleconnection patterns 210 7 on the variability of surface Pb and Be concentrations in south- Leppänen, A.P., Pacini, A.A., Usoskin, I.G., Aldahan, A., Echer, E., western Europe. J. Environ. Radioact. 165,103–114 (2016) Evangelista, H., Klemola, S., Kovaltsov, G.A., Mursula, K., Holton, J.R., Haynes, P.H., McIntyre, M.E., Douglass, A.R., Pfister, L.: Possnert, G.: Cosmogenic Be in air: a complex mixture of produc- Stratosphere-troposphere exchange. Rev. Geophys. 33(4), 403–439 tion and transport. J. Atmos. Sol. Terr. Phys. 72(13), 1036–1043 (1995) (2010). https://doi.org/10.1016/j.jastp.2010.06.006 Li, Y., Geng, X.C.: Effect of sample thickness on determination of Cs Hoskins, B.J., McIntyre, M.E., Robertson, A.W.: On the use and signif- and Pb using LabSOCS. Atomic Energy ence & Technology. icance of isentropic potential vorticity maps. Q. J. R. Meteorol. Soc. 44(1), 80–83 (2010) 111,877–946 (1985) 226 228 2l0 40 Hotzl, H., Winkler, R.: Activity concentrations of Ra, Ra, Pb, K Limpasuvan, V., Hartmann, D.L., Thompson, D.W.J., Jeev, K., Yung, and Be and their temporal variations in surface air. J. Environ. Y.L.: Stratosphere-troposphere evolution during polar vortex inten- Radioact. 5,445–5,458 (1987) sification. J. Geophys. Res. 110, D24101 (2005). https://doi.org/10. 1029/2005JD006302 Huh, C.A., Su, C.C.: Sedimentation dynamics in the East China Sea 210 137 239,240 elucidated from Pb, Cs and Pu. Mar. Geol. 160(1–2), Lozano, R.L., Hernández-Ceballos, M.A., Rodrigo, J.F., San Miguel, E.G., Casas-Ruiz, M., García-Tenorio, R., Bolívar, J.P.: Mesoscale 183–196 (1999). https://doi.org/10.1016/S0025-3227(99)00020-1 7 210 behavior of Be and Pb in superficial air along the gulf of Cadiz Hurrell, J.W.: Decadal trends in the North Atlantic oscillation region (south of iberian peninsula). Atmos. Environ. 80,75–84 (2013). temperatures and precipitation. Science. 269,676–679 (1995) https://doi.org/10.1016/j.atmosenv.2013.07.050 Hurrell, J. W., Kushnir, Y., Ottersen, G., & Visbeck, M. (2003). The Maenhaut, W., Zoller, W.H., Coles, D.G.: Radionuclides in the south North Atlantic oscillation: climate significance and environmental pole atmosphere. J. Geophys. Res. 84,3131–3138 (1979) impact. Geophysical monograph series, vol. 134, AGU, 7 32 90 210 Washington, D. C Marenco, A., Fontan, J.: Etude des variations des Be, P, Sr, Pb et Hurrell, J., Hoerling, M.P., Phillips, A.S., Xu, T.: Twentieth century Po dans la troposphere. Tetlus. 26,386–401 (1974) North Atlantic climate change. Part 1: assessing determinism. Matthews, K.M., Kim, C.K., Martin, P.: Determination of Po in envi- Clim. Dyn. 23,371–389 (2004) ronmental materials: a review of analytical methodology. Appl. Radiat. Isot. 65(3), 267–279 (2007). https://doi.org/10.1016/j. James, P., Stohl, A., Forster, C., Eckhardt, S., Seibert, P., Frank, A.: A 15- apradiso.2006.09.005 year climatology of stratosphere-troposphere exchange with a Lagrangian particle dispersion model. 2. Mean climate and seasonal Mishev, A.L., Kocharov, L.G., Usoskin, I.G.: Analysis of the ground variability. J. Geophys. Res. 108(D12), 8522 (2003). https://doi.org/ level enhancement on 17 May 2012 using data from the global 10.1029/2002JD002639 neutron monitoring network. J. Geophys. Res. Space Physics. 119, Jaworowski, Z., Kownacka, L., Bysiek, M.: Global distribution and 670–679 (2014). https://doi.org/10.1002/2013JA019253 sources of uranium, Radium-226, and Lead-210. In: Natural Pan, J.S., Wen, F.P., Chen, L., Ren, X.N., Zhang, J., Zhao, S.P., et al.: Radiation Environment III, vol. 1, pp. 383–404. Technical Preliminary analysis of activity concentration distributions of air- 210 210 Information Center, US Dept of Energy, Springfield (1980) borne Po and Pb in major cities in China. Radiation Protection. 37(6), 433–437 (2017) Jeong, J.H., Ho, C.H.: Changes in occurrence of cold surges over East Asia in association with Arctic oscillation. Geophys. Res. Lett. 32, Papastefanou, C.: Beryllium-7 aerosols in ambient air. Aerosol Air Qual. L14704 (2005) Res. 9(2), 187–197 (2009). https://doi.org/10.4209/aaqr.2009.01. Jevrejeva, S., Moore, J.: Singular spectrum analysis of Baltic Sea ice 0004 conditions and large-scale atmospheric patterns since 1708. Papastefanou, C., Ioannidou, A.: Aerodynamic size association of Be in Geophys. Res. Lett. 28(23), 4503–4506 (2001) ambient aerosols. J. Environ. Radioact. 26,273–282 (1995) Johnson, W., Viezee, W.: Stratospheric ozone in the lower troposphere: i. Press, W.H., Teukolsky, S.A., Vetterling, W.T., & Flannery, B.P. (1992). presentation and interpretation of aircraft measurements. Atmos. Numerical recipes in Fortran 77, 2nd ed., 933pp, Cambrideg Environ. 15,1309–1323 (1981) University Press, Cambridge, UK 210 7 Koch, D.M., Jacob, D.J., Graustein, W.C.: Vertical transport of tropo- Rastogi, N., Sarin, M.M.: Atmospheric Pb and Be in ambient aerosols 7 210 spheric aerosols as indicated by Be and Pb in a chemical tracer over low- and high-latitude sites in semiarid region: temporal Korean Meteorological Society X. Chen et al. variability and transport processes. J. Geophys. Res. Atmos. Visbeck, M.H., Hurrell, J.W., Polvani, L., Cullen, H.M.: The North 113(11), 1–14 (2008). https://doi.org/10.1029/2007JD009298 Atlantic oscillation: past, present, and future. Proc. Natl. Acad. Rehfeld, S., Heimann, M.: Three dimensional atmospheric transport sim- Sci. 98, (2001). https://doi.org/10.1073/pnas.231391598 ulation of the radioactive tracers 210Pb, 7Be, 10Be, and 90Sr. J. Wang, K.-Y., Chau, T.-T.: An association between air pollution and daily Geophys. Res. 100(D12), 26,141–26,161 (1995) outpatient visits for respiratory disease in a heavy industry area. San Miguel, E.G., Hernández-Ceballos, M.A., García-Mozo, H., Bolívar, PLoS One. 8(10), e75220 (2013). https://doi.org/10.1371/journal. J.P.: Evidences of different meteorological patterns governing Be pone.0075220 and Pb surface levels in the southern Iberian Peninsula. J. Wang, K.-Y., Kau, W.S.: Simulation of impact from stratospheric ozone Environ. Radioact. 198(December 2018), 1–10 (2019). https://doi. on global tropospheric ozone distribution with a chemistry transport org/10.1016/j.jenvrad.2018.12.007 model: a case study during the 1990-1991 period. Asia-Pac. J. Stein, A.F., Draxler, R.D., Rolph, G.D., Stunder, B.J.B., Cohen, M.D., Atmos. Sci. 51(2), 137–155 (2015) Nqan, F.: NOAA's HYSPLIT atmospheric transport and dispersion Wang, K.-Y., Pyle, J.A., Sanderson, M.G., Bridgeman, C.: modeling system. Bull. Am. Meteorol. Soc. 96,2059–2077 (2016) Implementation of a convective atmospheric boundary layer scheme Thompson, D.W.J., Lorenz, D.J.: The signature of the annular modes in in a tropospheric chemistry transport model. J. Geophys. Res. the tropical troposphere. J. Clim. 17(22), 4330–4342 (2004). https:// 104(D19), 23,729–23,745 (1999) doi.org/10.1175/3193.1 Wang, K.-Y., Shallcross, D.E., Pyle, J.A.: Seasonal variations and verti- Thompson, D.W.J., Wallace, J.M.: The Arctic oscillation signature in the cal movement of the tropopause in the UTLS region. Ann. Geophys. wintertime geopotential height and temperature fields. Geophys. 20(6), 871–874 (2002) Res. Lett. 25(9), 1297–1300 (1998). https://doi.org/10.1029/ WOUDC. (2021). Dataset information: OzoneSonde. Would Ozone and 98GL00950 Ultraviolet Radiation Data Centre. https://geo.woudc.org/def/data/ Thompson, D.W.J., Wallace, J.M.: Annular modes in the extratropical ozone/vertical-ozone-profile/ozonesonde, Version 1.30.0, doi: circulation. Part I: month-to-month variability. J. Clim. 13(5), 1000– https://doi.org/10.14287/10000008 1016 (2000) Wu, B.Y., Wang, J.: Winter Arctic oscillation, Siberian high and east Thompson, D.W.J., Wallace, J.M.: Regional climate impacts of the north- Asian winter monsoon. Geophys. Res. Lett. 29, 1897 (2002) ern hemisphere annular mode. Science. 293(5527), 85–89 (2001). Zhang, W., Chen, J., Ungar, K., Cooke, M.: Estimation of the Arctic https://doi.org/10.1126/science.1058958 aerosols from local and long-range transport using relationships be- Thompson, D.W., Wallace, J.M., Hegerl, G.C.: Annual modes in the 210 212 tween Pb and Pb atmospheric activity concentrations. J. extratropical circulation. Part II: Trends. J. Clim. 13,1018–1036 Environ. Radioact. 141,123–129 (2015) (2000) Zhao, S., Miller, A.J.: The interaction of the madden-Julian oscillation Tositti, L., Hübener, S., Kanter, H.J., Ringer, W., Sandrini, S., Tobler, L.: and the Arctic oscillation. J. Clim. 18,143–159 (2005) Intercomparison of sampling and measurement of Be in air at four Zheng, X., Wang, G., Tang, J., Zhang, X., Yang, W., Lee, H.N., et al.: high-altitude locations in Europe. Appl. Radiat. Isot. 61,1497–1502 7 210 Be and Pb radioactivity and implications on sources of surface (2004) 7 210 ozone at Mt. Waliguan. Chin. Sci. Bull. 50(2), 167–171 (2005) Turekian, K.K., Benninger, L.K., Dion, E.P.: Be and Pb total depo- sition fluxes at New Haven Connecticut and at Bermuda. J. Zhou, S., Miller, A.J., Wang, J., Angell, J.K.: Trends of NAO and AO Geophys. Res. 88,5411–5415 (1983) and their associations with stratospheric processes. Geophys. Res. UNSCEAR. (2000). Sources and effects of ionizing radiation, United Lett. 28,4107–4110 (2001) Nations Scientific Committee on the effects of atomic radiation UNSCEAR 2000 report to the general assembly, with scientific Publisher’sNote Springer Nature remains neutral with regard to jurisdic- annexes. In UNSCEAR 2000 Report: Vol. I tional claims in published maps and institutional affiliations. Usoskin, I.G., Kovaltsov, G.A.: Production of cosmogenic Be isotope in the atmosphere: full 3-D modeling. J. Geophys. Res. Atmos. 113(12), 1–12 (2008). https://doi.org/10.1029/2007JD009725 Korean Meteorological Society

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