近22a人为气溶胶对东亚地区夏季风环流影响的数值模拟研究

运用区域气候模式RegCM3耦合入一个化学过程,对东亚地区三类人为排放气溶胶（硫酸盐、黑碳和有机碳）的时空分布特征及其对夏季风环流的影响进行了数值模拟研究.模拟结果显示,气溶胶的引入会引起东亚地区夏季850 hPa风场发生改变,我国江淮以东洋面上空出现了一个气旋式距平环流中心,中心以西的偏北风气流将削弱东亚地区夏季西南季风.通过讨论春季中国地区气溶胶浓度与夏季东亚地区850 hPa经向风的时滞关系,以及夏季中国地区气溶胶浓度与同期东亚地区850 hPa经向风的关系,可以发现,春、夏季中国地区气溶胶浓度均与夏季东亚地区850hPa经向风有很好的负相关关系,当春季中国北方和夏季中国南方地区气溶胶浓度增加时,中国东部地区夏季偏南季风减弱.这可能与气溶胶改变了大气层顶和地表的辐射强迫,进而引起了海陆气压差异和位势高度场的变化有关.

Simulation of anthropogenic aerosols＆#39; effect on East Asian summer monsoon in recent 22 years

The anthropogenic aerosols （ sulfate, black carbon and organic carbon） and their effects on the East Asian summer monsoon have been simulated by using a regional climate model RegCM3 coupled with a chemistry aerosol model.Results show that aerosol can change summer 850 hPa wind over East Asia.A cyclonic anomaly circulation center appears on the estuary of the Yangtze River and the northerly air flow on its west will weaken the summer southwestly monsoon in East Asian.Investigation has been conducted on the relationship between spring and summer aerosol column burden over China and summer 850 hPa meridional wind in East Asia.Evidence shows that the aerosol column burden in both spring and summer bears a close negative correlation with summer 850 hPa meridional wind in East A- sia.The summer southerly monsoon in East China weakens when the spring aerosol column burden overNorth China or the summer aerosol column burden over South China increases.The reasons may be the short wave radiative forcing caused by aerosol effects on the top of the atmosphere and the surface, which leads to the change of air pressure and potential height between sea and land.