Numerical Simulation of the Effect of Soil Moisture on a Case of Plateau Vortex over Qinghai-Tibetan Plateau
ZHANG Huan;FAN Guangzhou;ZHANG Yongli;LAI Xin;School of Atmospheric Sciences/Plateau Atmosphere and Environment Key Laboratory of Sichuan Province/Joint Laboratory of Climate and Environment Change ,Chengdu University of Information Technology;Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters ,Nanjing University of Information Science and Technology;
Using the National Centers for Environmental Predication Final Analyses( NCEP-FNL) reanalysis data,the temperature of brightness blackbody( TBB) data from FY-2 E meteorological satellite,and the Climate Prediction Center morphing technique( CMORPH) precipitation data,the effect of soil moisture on a plateau vortex occurring from 16 to 17 August 2014 over Qinghai-Tibetan Plateau were analyzed on the numerical simulation for a control experiment and four sensitivity experiments by employing the WRF model( version 3. 8. 1).The results show that the vortex center,the vortex intensity and the vortex precipitation at 500 h Pa were simulated in the control experiment successfully. The soil moisture plays a key role in the intensity and precipitation of the vortex,how ever,it has no significant influence on the nature and moving path of the plateau vortex. Meanw hile,the soil moisture mainly influences the vortex by changing the surface latent heat flux and the surface sensible heat flux. When the soil moisture increases,the surface latent heat flux increases,and the instability of the air in middle and low atmosphere increases as well,which provides energy for the development of convective systems and increases the convective precipitation,leading to the strengthening of vortex intensity by increasing the release of the condensation heating. On the contrary,the intensity and precipitation of the plateau vortex are both weakened. In the paper,the change of the surface sensible heat flux has little effect on the formation of vortex,hence we just considered its impact on the convective precipitation. When the soil moisture increases,the surface skin temperature gets lower,the surface sensible heat flux decreases and the planetary boundary layer height( PBLH) decreases,thus increasing the moist static energy per unit mass of air,which increases the convective precipitation. Otherw ise,the convective precipitation decreases.
【Fund】： 国家自然科学基金项目(91537214 41275079 41305077 41305042 41405069 41505078);; 公益性(气象)行业科研专项(GYHY201506001);; 四川省教育厅重点项目(16ZA0203);; 成都信息工程大学中青年学术带头人科研基金(J201516 J201518)
【CateGory Index】： P461
【CateGory Index】： P461