期刊
ATMOSPHERIC ENVIRONMENT
卷 79, 期 -, 页码 299-307出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.atmosenv.2013.05.047
关键词
Rainwater; Sea-salt; Biomass burning; Backward trajectories; HYSPLIT; Long-range transport
资金
- FAPESP [03/01194]
- CAPES
- CNPq
The surface winds and backward trajectories were analyzed to investigate sources of sodium and potassium ions measured in rainwater in the metropolitan area of Sao Paulo (MASP), Brazil, from July-2002 to December-2005. In this study, we evaluated the chemical composition of 315 rainwater samples with focus on precipitation events with high concentrations of sodium and potassium, with cations concentrations, at least 1.5 times higher than the sulfate and nitrate concentrations. In the results from the total samples, the Na+ and K+ volume weighted mean (VWM) concentrations were 10.4 and 3.2 mu mol L-1, respectively, while for the excess events, the concentrations were 32.4 and 11.1 mu mol L-1. From the 31 sodium excess events, 45% showed an influence from ocean air masses by the wind direction evaluation while 57% of backward trajectories for 7 potassium excess events indicated a contribution of biomass burning air masses from the northwestern region of the Sao Paulo State. Although some excess events pointed the pattern of long-range transport, they represented less than 15% of total samples. The results suggest that the megacity itself is predominantly involved in the process of emission and removal of the compounds and the influence of external components are limited to circumstantial events. (C) 2013 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据