摘要
The spatial distribution, radiative forcing, and climatic effects of tropospheric ozone in China during summer were investigated by using the regional climate model Reg CM4. The results revealed that the tropospheric ozone column concentration was high in East China, Central China, North China, and the Sichuan basin during summer. The increase in tropospheric ozone levels since the industrialization era produced clear-sky shortwave and clear-sky longwave radiative forcing of 0.18 and 0.71 W m^(–2), respectively, which increased the average surface air temperature by 0.06 K and the average precipitation by 0.22 mm day^(–1) over eastern China during summer. In addition, tropospheric ozone increased the land–sea thermal contrast, leading to an enhancement of East Asian summer monsoon circulation over southern China and a weakening over northern China. The notable increase in surface air temperature in northwestern China, East China, and North China could be attributed to the absorption of longwave radiation by ozone, negative cloud amount anomaly, and corresponding positive shortwave radiation anomaly. There was a substantial increase in precipitation in the middle and lower reaches of the Yangtze River. It was related to the enhanced upward motion and the increased water vapor brought by strengthened southerly winds in the lower troposphere.
The spatial distribution, radiative forcing, and climatic effects of tropospheric ozone in China during summer were investigated by using the regional climate model Reg CM4. The results revealed that the tropospheric ozone column concentration was high in East China, Central China, North China, and the Sichuan basin during summer. The increase in tropospheric ozone levels since the industrialization era produced clear-sky shortwave and clear-sky longwave radiative forcing of 0.18 and 0.71 W m^(–2), respectively, which increased the average surface air temperature by 0.06 K and the average precipitation by 0.22 mm day^(–1) over eastern China during summer. In addition, tropospheric ozone increased the land–sea thermal contrast, leading to an enhancement of East Asian summer monsoon circulation over southern China and a weakening over northern China. The notable increase in surface air temperature in northwestern China, East China, and North China could be attributed to the absorption of longwave radiation by ozone, negative cloud amount anomaly, and corresponding positive shortwave radiation anomaly. There was a substantial increase in precipitation in the middle and lower reaches of the Yangtze River. It was related to the enhanced upward motion and the increased water vapor brought by strengthened southerly winds in the lower troposphere.
基金
Supported by the National Key Research and Development Plan of China(2016YFC0203303)
National(Key)Basic Research and Development(973)Program of China(2014CB441203)
National Natural Science Foundation of China(91544230,41621005,41575145,and 41205109)
REgional climate–air QUAlity interactions(REQUA)project of Marie Curie Actions International Research Staff Exchange Scheme(IRSES)under the 7th Framework Programme of the European Community(PIRSES-GA-2013-612671)