一次沙尘天气过程中沙尘气溶胶对辐射的影响  

Dust Aerosol Influence on Radiation During a Dust Weather Process

作　　者：周旭[1] 张镭[1] 孙乃秀 高兴艾 

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

出　　处：《干旱气象》2016年第5期763-771,共9页Journal of Arid Meteorology

基　　金：国家自然科学基金创新研究群体科学基金"干旱半干旱气候变化机理"(41521004);国家自然基金面上项目(41475008)共同资助

摘　　要：沙尘气溶胶对辐射有显著影响,利用耦合了Shao2004起沙参数化方案的WRF/Chem(大气/化学全耦合模式),模拟分析了沙尘天气过程中沙尘气溶胶对辐射的影响。结果发现沙尘气溶胶可以导致地面向下的短波辐射通量减小42.51%,平均减小-3.30^-49.46 W·m^(-2),最大可达-162.67 W·m^(-2);沙尘气溶胶可以通过自身向外发射长波辐射,导致地面向下的长波辐射通量增大,地面向下的长波辐射通量平均增加为17.49~50.49 W·m^(-2),最大可达99.17 W·m^(-2)。当PM10浓度为10~20 mg·m-3,沙尘气溶胶能够减小地面向下的长波辐射通量,即沙尘气溶胶在该地区对大气具有"保温"作用;白天沙尘气溶胶主要增加大气层顶向上的长波辐射通量,夜间则减少大气层顶向上的长波辐射通量,大气层顶向外的长波辐射通量平均变化为-25.29~28.83 W·m^(-2),最大可达87.22 W·m^(-2)。Dust aerosols play an important role in radiation budget. Aerosol-radiation interactions during dust storms were studied by implementing dust emission scheme by Shao（ 2004）（ hereinafter referred to as Shao 2004 scheme） in Weather Research and Forecasting with Chemistry（ WRF / Chem）. Downward short wave radiation flux at ground surface was reduced by an average of 42. 51%,with hourly average range from-3. 30 to-49. 46 W·m-2,and the instantaneous maximum was-162. 67 W·m-2. Dust aerosol radiation emission enhanced the downward long wave radiation flux at ground surface,with hourly average range from 17. 49 to 50. 49 W·m-2,and the instantaneous maximum was 99. 17 W · m-2. The downward long wave radiation flux at ground surface was reduced in the region with PM10 concentrations ranging from 10 to 20 mg·m-3,and the reduced radiation was reserved in the atmosphere and kept the air warm. Daytime dust aerosols mainly enhanced the outgoing radiation flux at the top of atmosphere（ TOA）,while nighttime theymainly reduced outgoing radiation flux at TOA. The outgoing radiation flux at TOA ranged from-25. 29 to ＋ 28. 83 W·m-2,with an instantaneous maximum of 87. 22 W·m-2.

关 键 词：沙尘气溶胶 短波辐射通量 长波辐射通量 向外长波辐射通量 

分 类 号：P422.9[天文地球—大气科学及气象学]