青藏高原东南部及其邻近地区FY-2E卫星晴空大气可降水量评估

EVALUATION OF TOTAL PRECIPITABLE WATER DERIVED FROM FY-2E SATELLITE DATA OVER THE SOUTHEAST OF TIBETAN PLATEAU AND ITS ADJACENT AREAS

为了解青藏高原东南部及邻近地区FY-2E卫星大气可降水量（FY-2ETPW）的可靠性,利用2010-2012年探空计算值（RS TPW）对其进行对比分析。结果表明：青藏高原地区月平均FY-2ETPW除7月偏小外,其余月份都偏大,相对偏差仅有6月和7月在25%以内,其余月份都在50%以上,尤其是1月高达780.45%,FY-2ETPW与RS TPW之间为负相关系数,FY-2ETPW在青藏高原地区不可靠;低海拔地区,6月和7月平均FY-2ETPW偏小,其余月份都偏大,5-8月相对偏差不足4%,但1月相对偏差却高达105.84%;低海拔地区4-10月,FY-2E TPW与RS TPW相关系数大于0.5,FY-2ETPW订正模型估计标准误差为6.57mm,个别站点误差较大,还有待进一步的改进。

In order to understand the reliability of total precipitable water vapor（TPW）derived from FY-2E satellite data over the Southeast of Tibetan Plateau and its adjacent areas,FY-2ETPWs are compared with the radiosonde（RS）TPWs during the period from 2010-2012.The results show that over the Tibetan Plateau the average monthly FY-2ETPWs are larger than RS TPWs except in July.The relative errors are less than 25% in June and July and more than 50% in other months,especially in January as high as780.45%.The correlation coefficient between FY-2E TPW and RS TPW is negative.Over the low altitudes the average monthly FY-2ETPWs are larger than RS TPWs in June and July and smaller in other months.The relative errors are less than 4%in May to August,but in January as high as 105.84%.The correlation coefficient is greater than 0.5during the period from April to October.The linear correction model of FY-2E TPW with a standard error of 6.57 mm could be improved to count error in individual sites.