江西地区气候变暖的增湿效应研究

应用江西地区近45 a的气温、降水、水汽压、蒸发量等常规观测资料,对比分析了气温与降水的关系,并试图在此基础上,利用第二类热成风螺旋度来理解江西地区自20世纪80年代中期以来气候变暖的湿旋转效应.研究结果发现,1959～1969年,江西地区气温降低时,第二类热成风螺旋度下降,导致降水量减少.1970～1983年,气温、降水和第二类热成风螺旋度的变化幅度均较小.1984～2003年,气温上升时,第二类热成风螺旋度上升,引起湿旋转作用加强,从而进一步加速大气中的水汽凝结,形成更多的降水;与此同时,地面蒸发量却减少,导致地表水增加,引发更多的地质灾害,造成更大的经济损失.

A PRIMARY ANALYSIS OF DAMP ROTATION EFFECT OF CLIMATIC WARMING OVER JIANGXI REGION

The relations among temperature,precipitation,water vapor and evaporation over Jiangxi region in the last 45 years are analyzed and second thermal wind helicity is used to understand the damp rotation effect of climatic warming from medium-term 1980s.It shows that from 1959 to 1969,precipitation is actually decreased when temperature and second thermal wind helicity are decreased,whereas temperature,precipitation and second thermal wind helicity are steady from 1970 to 1983,and precipitation is increased when temperature and second thermal wind helicity are increased from 1984 to 2003.Furthermore,it indicates that,climatic warming has induced increase of second thermal wind helicity,which lead to condensation of more and more water vapor,and then much water falls to the ground.The precipitation is increased while the evaporation is decreased,which has caused much flood and more mountain landslides.