高温对海南岛西南部干旱影响研究

Analysis on the Effect of High Temperature on Drought in Southwestern Hainan Island

利用1966—2018年海南岛18个台站逐日降水和高温资料,对海南岛西南部干旱与高温进行相关分析。结果表明:海南岛西南部4—6月高温、干旱的空间分布较为相似,西南部高温多,也是干旱的易发地;降水极端偏少年与高温日数的极端偏多年有较好的一致性,均出现重大干旱灾害,这说明高温过程的出现会加重气象干旱的发展。利用NCEP/NCAR再分析资料对比分析4—6月极端旱年和涝年大气环流异常特征,发现阻塞高压、东亚大槽和阿留申低压偏弱,南亚高压偏强,海南岛上空为反气旋式异常环流,高层辐合、低层辐散,是造成4—6月海南岛西南部高温干旱的异常环流背景。

Based on the daily precipitation and high temperature data of 18 meteorological stations in Hainan Island from 1966 to 2018,the correlation between drought and high temperature in Southwestern Hainan Island was analyzed.The result shows that in Southwestern Hainan Island,with more frequency high temperature days and drought,the spatial distributions of high temperature and drought from April to June are comparatively similar,and the consistency between the years with extremely less precipitation and the years with extremely more high temperature days is good.In each of those years,there were severe drought disasters,which indicated that the high temperature contributed to the development of meteorological drought.NCEP/NCAR reanalysis monthly average data are used to compare and analyze the atmospheric circulation anomalies from April to June in extreme drought and flood years.It indicates that the weak blocking high,East Asian trough and Aleutian lower,strong South Asia high,and the abnormal anticyclonic air circulation over Hainan Island,high-level convergence and low-level divergence formed the abnormal circulation background of high temperature and drought weathers in Southwestern Hainan Island from April to June.