State Key Laboratory of Severe Weather & Key Laboratory of Atmospheric Chemistry of CMA, Chinese Academy of Meteorological Sciences, Beijing 100081, China.
State Key Laboratory of Severe Weather & Key Laboratory of Atmospheric Chemistry of CMA, Chinese Academy of Meteorological Sciences, Beijing 100081, China; Center for Excellence in Regional Atmospheric Environment, IUE, CAS, Xiamen 361021, China.
Sci Total Environ. 2018 Jul 15;630:46-52. doi: 10.1016/j.scitotenv.2018.01.236. Epub 2018 Feb 20.
Winter is a season of much concern for aerosol pollution in China, but less concern for pollution in the summertime. There are even less concern and larger uncertainty about interdecadal changes in summer aerosol pollution, relative influence of meteorological conditions, and their links to climate change. Here we try to reveal the relation among interdecadal changes in summer's most important circulation system affecting China (East Asian Summer Monsoon-EASM), an index of meteorological conditions (called PLAM, Parameter Linking Air Quality and Meteorological Elements, which is almost linearly related with aerosol pollution), and aerosol optical depth (AOD) in the middle and lower reaches of the Yangtze River (M-LYR) in central eastern China during summertime since the 1960's. During the weak monsoon years, the aerosol pollution load was heavier in the M-LYR and opposite in the strong monsoon years mainly influenced by EASM and associated maintenance position of the anti-Hadley cell around 115°E. The interdecadal changes in meteorological conditions and their associated aerosol pollution in the context of such climate change have experienced four periods since the 1960's, which were a relatively large decreased period from 1961 to 1980, a large rise between 1980 and 1999, a period of slow rise or maintenance from 1999 to 2006, and a relatively rapid rise between 2006 and 2014. Among later three pollution increased periods, about 51%, 25% and 60% of the aerosol pollution change respectively come from the contribution of worsening weather conditions, which are found to be greatly affected by changes in EASM.
冬季是中国气溶胶污染的一个备受关注的季节，但夏季的污染则较少受到关注。对于夏季气溶胶污染的年代际变化、气象条件的相对影响及其与气候变化的联系，人们的关注更少，不确定性更大。在这里，我们试图揭示影响中国的最重要环流系统（东亚夏季风-EASM）、气象条件指数（称为 PLAM，气象要素与空气质量的参数关联，与气溶胶污染几乎呈线性相关）和中国中东部长江中下游地区（MLYR）夏季气溶胶光学深度（AOD）之间的关系。在东亚夏季风较弱的年份，MLYR 的气溶胶污染负荷较重，而在东亚夏季风较强的年份，气溶胶污染负荷较轻，主要受 EASM 及其在 115°E 左右的反哈德利环流维持位置的影响。自 20 世纪 60 年代以来，在气候变化背景下，气象条件及其相关气溶胶污染的年代际变化经历了四个时期，分别是：1961 年至 1980 年的相对较大下降期、1980 年至 1999 年的大幅上升期、1999 年至 2006 年的缓慢上升或维持期，以及 2006 年至 2014 年的相对快速上升期。在后三个污染上升期，气溶胶污染变化的约 51%、25%和 60%分别来自气象条件恶化的贡献，这发现受 EASM 变化的极大影响。
