State Key Laboratory of Severe Weather and Key Laboratory of Atmospheric Chemistry of CMA, Chinese Academy of Meteorological Sciences, Beijing 100081, China.
National Meteorological Centre, Beijing 100081, China.
Sci Total Environ. 2019 Nov 25;693:133448. doi: 10.1016/j.scitotenv.2019.07.254. Epub 2019 Jul 21.
Upper air and surface data from 1960 to 2016, NCEP reanalysis from 1990 to 2016, air composition data from 2015 to 2016, and data from the drift automatic weather station in the Arctic from August 2012 to February 2013 are used to analyze the heavy foggy haze in China from a global perspective. Our findings show that sensitive foggy haze in winter is located in the eastern region of China because of the comprehensive effect of multi-factor meteorological conditions and the response to climate change under global warming as follows. (1) For the past half-century, two winter monsoon airflows blow from the East Asian continent and adjacent sea to North China. The airflow in the intermediate zone (North China) between the two winter monsoon airflows generates a retained circulation owing to the Earth's rotation because wind velocities over land and sea are different and their wind intensities are weakened. The circulation retention index has been on the rise in recent years, causing a "static stability" that retains or stabilizes air masses over this area. (2) Under global warming, polar ice has shrunk to a historical lowest over the years. The melting polar ice results in explosive heating and humidification in the lower troposphere leading to increased aerosol concentrations, which is conducive to maintaining or strengthening the Arctic haze. (3) The two winter monsoon pathways run over the Eurasian continent and the surface of the adjacent Sea of Okhotsk, thus affecting North China. These results are consistent with the airflow of the pollutant conveyor belt channeling from the Arctic haze zone. As a result, the pollutant conveyor belt from the Arctic haze zone as well as the pollutant conveyor belts from West Asia and North Africa contribute substantially to the high frequency of winter foggy haze over eastern China.
利用 1960 年至 2016 年的高空和地表数据、1990 年至 2016 年的 NCEP 再分析数据、2015 年至 2016 年的空气成分数据以及 2012 年 8 月至 2013 年 2 月北极漂流自动气象站的数据，从全球角度分析了中国的浓雾霾天气。我们的研究结果表明，由于多因素气象条件的综合影响以及全球变暖背景下对气候变化的响应，冬季敏感浓雾霾位于中国东部地区。（1）在过去的半个世纪里，东亚大陆和临近海域的两股冬季季风气流吹向中国北方。由于陆地和海洋风速不同且风速减弱，两股冬季季风气流之间的中纬度地区（华北地区）产生了保留环流。近年来，环流保留指数呈上升趋势，导致该地区出现“静稳”现象，保留或稳定了大气团。（2）在全球变暖的情况下，极地冰盖近年来已缩小到历史最低水平。极地冰的融化导致低层大气急剧升温加湿，气溶胶浓度增加，有利于维持或加强北极霾。（3）这两股冬季季风路径经过欧亚大陆和临近的鄂霍次克海表面，从而影响到华北地区。这些结果与污染物输送带从北极霾区输送污染物的气流一致。因此，来自北极霾区的污染物输送带以及来自西亚和北非的污染物输送带，对中国东部冬季频繁出现浓雾霾天气起到了重要作用。
