摘要
根据高原特点修订后的对流指数公式,使用大气红外探测仪(AIRS)反演的温湿参量,对2013年5月3—5日发生于青藏高原东南部的1次强降水过程中的中尺度对流系统(MCSs)进行分析,得出AIRS资料的多产品、高精度、高空间分辨率的优势可在一定程度上弥补青藏高原上探空资料严重不足的缺点.K指数在MCSs发展过程中存在由大减小的特点,最大对流稳定度指数(BI)出现在MCSs的低值中心,并且低值中心随云顶亮温的低值中心移动;沙氏(SI)指数的低值区先于MCSs而形成,大致为0~5℃,说明在MCSs发展前高原大气就已出现热力不稳定,有利于强对流天气的形成.上述3个对流指数在MCSs发展过程中都出现了低值区,但低值中心并不重合,并呈现不同的变化特征,提示我们采取对流指数作为高原对流天气辅助分析预报信息时,需要综合加以应用.
Using the parameter of temperature and humidity inversed by Atmospheric Infrared Sounding （AIRS） and according to the formula of convective index that has been revised based on trait of the plateau,we have analyzed the Mesoscale Convective Systems （MCSs） in an heavy rainfall process happened in southeast of Tibetan Plateau on May 3 to 5,2013.The result is that because of the advantage of the AIRS data that multiproduct, high precision and high spatial resolution, it can make up for the shortage caused by serious deficiency of sounding data in Tibetan Plateau.The K index is characterized of variation from high to low, maximum convective stability index （BI） has the low center which moves towards low center of Black Body Temperature.The low value zone of Showalter Index （SI） tends to form before MCSs, approximately from 0 to 5 ℃ .It illustrates that the at- mosphere over the Tibetan Plateau is already unstable before the MCSs formation.It is favorable for the formation of strong convective weather.These three convective indexes all have the low area in the process of development of MCSs, but the low area is not misaligned, and presents three characteristics of change. These conclusions remind us to consider the convective index comprehensively, when using convective index as assistant information for analyzing and forecasting weather.
出处
《云南大学学报（自然科学版）》
CAS
CSCD
北大核心
2017年第1期88-97,共10页
Journal of Yunnan University(Natural Sciences Edition)
基金
国家自然科学基金(91337215
41675057)
财政部
科技部公益性行业(气象)科研专项(GYHY201206042)
