区域海气耦合模式RIEMS2.0-POM2K模拟的黑碳气溶胶对东亚春夏气候的影响  

The Regional Sea Air Coupled Model(RIEMS2.0-POM2K)Simulated the Affecting of Black Carbon Aerosol on the Spring and Summer Climate over East Asia

作　　者：罗敏 吴涧[2] LUO Min;WU Jian(Key Laboratory for Semi-Arid Climate Change of the Ministry of Education,College of Atmospheric Sciences,Lanzhou University,Lanzhou 730000,Gansu,China;Department of Atmospheric Science,Yunnan University,Kunming 650091,Yunnan,China)

机构地区：[1]兰州大学大气科学学院半干旱气候变化教育部重点实验室,甘肃兰州730000 [2]云南大学资源环境与地球科学学院大气科学系,云南昆明650091

出　　处：《高原气象》2020年第4期870-888,共19页Plateau Meteorology

基　　金：国家自然科学基金项目(41675149,41675178)。

摘　　要：黑碳气溶胶的辐射强迫及其对东亚的气候效应仍有较大不确定性,同时在黑碳气溶胶气候效应的研究中对海洋的关注较少。为了量化分析黑碳气溶胶直接辐射效应和分析其通过海气相互作用对东亚夏季风的影响,用区域海气耦合模式进行黑碳气溶胶离线模拟的敏感试验。试验结果表明:东亚晴空大气顶和地面的净辐射强迫在春季分别为1.58 W·m^-2和-2.75 W·m^-2,在夏季分别为1.68 W·m^-2和-2.62 W·m^-2。受黑碳气溶胶辐射效应影响,大气变暖,大气热力稳定度增加,云量减少。春季黑碳气溶胶的"热泵效应"引起华南降水增加和夏季风提前爆发。夏季孟加拉湾海表降温,南支槽加深,引起华南降水增加;另外中纬度附近经向温度梯度增大,进而增强冷空气势力和水汽辐散,引起华北降水减少。华南降水正异常和华北降水负异常有利于"南涝北旱"。黑碳气溶胶辐射效应能通过海气相互作用增加热带海表温度,减小经向温度梯度和海陆热力差异,进而减弱夏季风。此外,黑碳气溶胶辐射效应也能增强局域哈德莱环流及北风,进而减弱夏季风。The radiative forcing of black carbon aerosol(BC)and its effects on the climate of East Asia still have significant uncertainties.Moreover,little attention has been paid to the ocean in the study of climate effects of BC.In order to quantitavely analyze the direct radiative forcing of BC and its effect on East Asia summer monsoon through the sea air interactions,here the sensitivity experiments of the off-line simulation of BC was carried out by using the regional air sea coupling model.The results of sensitivity experiments show that the clear sky net direct radiative forcing under clear-sky conditions over East Asia is 1.58 W·m^-2 at the top of atmosphere(TOA)and-2.75 W·m^-2 at the surface in spring respectively,and 1.68 W·m^-2 on TOA and-2.62 W·m^-2 on the surface in summer respectively.Effected by the radiative effects of BC,the atmosphere gets warmer,the thermal stability of atmosphere increases,while the cloud cover decreases.In spring,the"Elevated Heat Pump"effect of BC causes the increased precipitation over the South China(SC)and the advanced summer monsoon.In summer,the radiative effects of BC cause a cooling effect on the Bengal Bay and then reinforce the South Trough,which results in the increased precipitation over SC;Furthermore,the increased meridional temperature gradient around the middle latitude can enhance the force of cold air and the divergence of water vapor,which can induce the decreasing of the precipitation over the North China(NC).The positive anomaly of the precipitation over SC and the negative anomaly of the precipitation over NC favor the"southern flood and northern drought".The radiative effects of BC can raise the tropical sea surface temperature(SST)while decrease the meridional SST gradient and the sea land thermal contrast through the sea air interactions,that will lead to a weak summer monsoon.In addition,the radiative effects of BC can also enhance the local Hadley circulation and the northerly wind,and then weaken the summer monsoon.

关 键 词：黑碳气溶胶 直接辐射强迫 气候效应 夏季风 区域海气耦合模式 

分 类 号：P401[天文地球—大气物理学与大气环境]