论文部分内容阅读
利用1982—2009年全球热带云团数据集、NCEP/NCAR再分析资料和英国Hadley中心海温资料,并引入热带云团生成率(Genesis Productivity,GP)来分析EP(Eastern Pacific)El Nio和CP(Central Pacific)El Nio事件与西北太平洋热带云团发展的相关性。研究表明,1)夏秋两季GP与Nio3指数在东南区(SE)均为显著正相关,在西南区(SW)仅秋季呈显著正相关;GP与EMI(El Nio Modoki Index)指数在夏季SE区域为显著正相关,在秋季南中国海(South China Sea,SCS)区呈负相关。2)在EP El Nio年,夏季SE区域的GP增大与低层涡度、高层散度以及低层相对湿度的相对增大一致。夏季SW区域与秋季SE区域的GP增大与有利的高低空配置相关,La Nia年则与之相反。3)在CP El Nio年,夏季SE区域的GP增大伴随着低层涡度和高层散度的增加,同时与充足的水汽及弱风切变相吻合;而秋季SCS区域的GP下降源于正涡度带、正散度带以及水汽带的东移。
EP (Eastern Pacific) El Nio was analyzed using global tropical cloud data from 1982-2009, NCEP / NCAR reanalysis data and sea temperature data from Hadley Center, England, and the introduction of Genesis Productivity (GP) And CP (Central Pacific) El Nio event and the development of the tropical Pacific Northwest Pacific. The results showed that there was a significant positive correlation between GP and Ni o3 index in the SE region in summer and autumn, and significant positive correlation in autumn only in the SW region. GP and EMI (El Ni o Modoki Index) The index was significantly positively correlated in summer SE and negatively correlated in autumn South China Sea (SCS). 2) During the EP El Niño year, the GP increase in the summer SE region is consistent with the relative increase in low-level vorticity, high-level divergence, and low-level relative humidity. The increase of GP in summer SW and autumn SE is related to the favorable altitude configuration, while La Nia is the opposite. 3) During the CP El Nio year, the increase of GP in the summer SE region was accompanied by the increase of low-level vorticity and high-level divergence, coinciding with sufficient water vapor and weak wind shear. In autumn, the GP of SCS decreased from Positive vorticity zone, positive divergence zone and water vapor zone eastward.