Influence of long-range atmospheric transport pathways and climate teleconnection patterns on the variability of surface 210Pb and 7Be concentrations in southwestern Europe

Abstract

The variability of the atmospheric concentration of the Be andPb radionuclides is strongly linked to the origin of air masses, the strength of their sources and the processes of wet and dry deposition. It has been shown how these processes and their variability are strongly affected by climate change. Thus, a deeper knowledge of the relationship between the atmospheric radionuclides variability measured close to the ground and these atmospheric processes could help in the analysis of climate scenarios. In the present study, we analyze the atmospheric variability of a 14-year time series of Be andPb in a Mediterranean coastal city using a synergy of different indicators and tools such as: the local meteorological conditions, global and regional climate indexes and a lagrangian atmospheric transport model. We particularly focus on the relationships between the main pathways of air masses and sun spots occurrence, the variability of the local relative humidity and temperature conditions, and the main modes of regional climate variability, such as the North Atlantic Oscillation (NAO) and the Western Mediterranean Oscillation (WeMO). The variability of the observed atmospheric concentrations of both Be andPb radionuclides was found to be mainly positively associated to the local climate conditions of temperature and to the pathways of air masses arriving at the station. Measured radionuclide concentrations significantly increase when air masses travel at low tropospheric levels from central Europe and the western part of the Iberian Peninsula, while low concentrations are associated with westerly air masses. We found a significant negative correlation between the WeMO index and the atmospheric variability of both radionuclides and no significant association was observed for the NAO index.

Determining the Sources and Transport of Brown Carbon Using Radionuclide Tracers and Modeling

“…These two radionuclides are immediately attached to submicron aerosol particles after entering the atmosphere and are removed mainly through depositional processes. The unambiguous sources and stable chemical properties make these radionuclides useful indicators of continental transport and the stratosphere‐troposphere exchange processes affecting submicron aerosols (Grossi et al., 2016; Hammer et al., 2007; Lin, Huh, et al., 2014).…”

“…210 Pb has a longer half‐life of 22.3 years and is the decay product of gaseous radon‐222. Radon‐222 is almost entirely produced from radium, which is ubiquitously present in soils, with marine systems contributing only 1% of soil‐emitted radon‐222 to the atmosphere (Grossi et al., 2016; Lin, Huh, et al., 2014). These two radionuclides are immediately attached to submicron aerosol particles after entering the atmosphere and are removed mainly through depositional processes.…”

Meteorological Factors Controlling 7Be Activity Concentrations in the Atmospheric Surface Layer in Northern Spain

“…However, the complexity of the interactions of all mechanisms modulating 7 Be concentrations near the surface makes it difficult to understand it's surface temporal and spatial variability. Previous studies have already described the connection of 7 Be concentrations in the lower troposphere and solar activity [10], wet scavenging [11], the exchange between the stratosphere and the troposphere [12], the tropospheric vertical mixing [13], and the horizontal transport [14].…”

“…Many studies have evaluated 7 Be concentrations in surface air and its relationship with meteorological factors at different scales across the Iberian Peninsula. Analysis carried out in the west (in Lisbon [15]), in the east (in Valencia [16]; in Barcelona [14]) and in the south (in Huelva [17]; in Huelva and Cordoba [18]; in Malaga [19,20]; in Granada [21]) provide a wide mosaic about the spatial distribution and the meteorological conditions regulating the temporal and seasonal variations of 7 Be in surface air in the Iberian Peninsula. In the northern part, where climatic conditions are quite different from those prevailing in more southern latitudes, the number of studies analyzing 7 Be activity concentrations, but its link with meteorological factors are scarce.…”

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

“…Moreover, temporal and spatial variations in this ratio reflect both vertical and horizontal transport in the atmosphere (Koch et al 1996;Baskaran 2011). Due to their halflives (22.3 years for 210 Pb and 53.2 days for 7 Be), both natural radionuclides can persist long enough for longrange transport in the atmosphere (Zhang et al 2015;Grossi et al 2016;San Miguel et al 2019).…”