Long-range atmospheric transport Beryllium-7 to region the Sea of Japan

摘要

Concentrations of cosmogenic beryllium-7(Be-7) and atmospheric aerosols were measured in the atmosphere of the coastal zone of Vladivostok in 2013-2014. The 7Be concentrations ranged from 0.5 to 4.1 mBq/m(3), with the lowest values in summer and the highest in spring and autumn; the mean value was 2.2 mBq/m(3). Analysis of meteorological data in the synoptic scale showed an inverse correlation with wet deposition rates R = -0.55 (p = 0.0001) and H2O mixing ratio R = -0.49 (p = 0.0001) and a positive with an average maximum height of 120-h backward trajectories of air masses R = 0.65 (p = 0.0001). Angular cluster analysis showed the Be-7 concentration to be dependent on the northwestern (R = 0.53, p = 0.001) and eastern winds (R = -0.7, p = 0.0001 for 2013 and R = -0.49, p = 0.002 for 2014). The multiple regression analysis identified five factors in Be-7 concentration: altitudes (b = 0.44), air temperature (b = 0.36), a portion of trajectories in the pacific (North-East direction) cluster (b = -0.32), aerosol concentrations (b = 0.28) and wet precipitation rates (b = -0.24). The model has a good correlation with the data (adjusted R-2 = 0.55). It was found that the direction and height of the air masses trajectories in the lower troposphere strongly influence the concentration of Be-7. (C) 2016 Published by Elsevier Ltd.