G20峰会期间杭州市大气区域输送特征研究

Study on the Regional Air Transport Characteristics of Hangzhou During the G20 Summit

利用拉格朗日扩散模型评估G20峰会期间杭州市大气区域输送特征,结果表明,G20峰会开幕期间杭州市的气团来源由西南内陆转为杭州湾和东海地区,且传输速度较快,空气污染得到显著清除。保障期间污染情形下,苏北、安徽、江西等地的气团输送更强,浙北和苏南地区输送减弱。在管控情形下,浙北的PM2.5一次排放潜在贡献降低了15%,减排管控措施有效降低了周边地区一次排放对杭州市的空气污染输送。1981—2016年G20峰会历史同期,浙江省对杭州市的气团贡献年际变化幅度为26%~85%,平均贡献为63%。

Using the Lagrangian particle release model(LPDM)to evaluate the characteristics of atmospheric transport in Hangzhou during the G20 summit.The results show that during the opening of the summit,the source of air masses in Hangzhou changed from the southwestern inland to the Hangzhou Bay and the East China Sea.The transmission speed was faster,and the air pollution was significantly cleared.Under the situation of pollution during the period of the G20 summit,the air mass transportation was stronger in the northern Jiangsu,Anhui,Jiangxi and other places,and was weakened in the north Zhejiang and south Jiangsu.The potential concentration of PM2.5 in northern Zhejiang was reduced by 15%under control scenario,and the PM2.5 transport from surrounding areas to Hangzhou was effectively reduced by the emission reduction control measures.The annual variations of Zhejiang’s air mass contributions to Hangzhou were 26%-85%and the average contribution was 63%during the protection time and the G20 summit conference from 1981 to 2016.