Analysis on vapor field for the drought over Southwest in 2009–2010

By using the regional climate model RegCM3 this paper simulated the drought over Southwest China during 2009 and 2010. By using to the NCEP reanalysis data this paper analyzed the impact of the atmospheric precipitable water, the water vapor transport and the water vapor budget. The result showed that: atmospheric precipitable water was less about 20% than normal years during the drought. The meridional water vapor transport was more than normal years and there was no big difference between the zonal water vapor transport before December 2009, but the situation after January 2010 was just contrary to it: the zonal water vapor transport was more and the meridional water vapor transport was similar to the normal years. The synthetic function of the zonal and meridional water vapor transport caused the water payout more than normal years during the drought.