Mesoscale behavior of 7Be and 210Pb in superficial air along the Gulf of Cadiz (south of Iberian Peninsula)

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210Pb and 7Be activity concentrations in surface air and in bulk deposition have been measured from November 2009 to December 2011 along the Gulf of Cadiz (Southwest of Spain). This area presents mesoscale variations in its meteorological conditions, with influence of air masses with different origins: maritime, either from the Atlantic Ocean or the Mediterranean Sea and continental, from Iberian Peninsula and north of Africa, which make possible this region to be suitable to analyse the mesoscale spatial and temporal variations of atmospheric compounds. The objective of this study is to determine if there are differences in 210Pb and 7Be activity concentrations in surface air and in bulk deposition at the mesoscale level in this complex area of southwestern Iberian Peninsula taking as reference two sites of the same geographical area but influenced by different meteorological conditions.The temporal evolution pattern of PM10 was different for each site (no correlation between both series was found), but the PM10 average concentrations were similar for both locations (differences were not found at 0.05 significance level). On the other hand, the temporal evolution of 7Be and 210Pb activity concentrations in surface air show a good correlation between both sites, indicating this fact a similar behaviour of these radionuclides in the area.Finally, for each location a strong correlation between 210Pb and 7Be depositional fluxes was also observed, showing that wet deposition plays a key role in the deposition fluxes of both radionuclides. The averages depositional fluxes for 7Be and 210Pb are 750 Bq m−2 y−1 and 60 Bq m−2 y−1 in both locations, respectively.This set of results allows to determine that both radionuclides (7Be and 210Pb) present similar atmospheric behaviours, although with mesoscale variations in the magnitude of the values along the entire southern coast of the Iberian Peninsula.