Based on the reanalysis data of global 500hPa geopotential height (NCEP NCAR CDAS-1) and tropical Pacific SSTs, the characteristics of global subtropical highs and their response to tropical eastern Pacific SST are i...Based on the reanalysis data of global 500hPa geopotential height (NCEP NCAR CDAS-1) and tropical Pacific SSTs, the characteristics of global subtropical highs and their response to tropical eastern Pacific SST are investigated. Results show that global subtropical highs respond to SST consistently. Subtropical high intensity correlates to the 3 months leading SST maximally. The relationship between SST and 500hPa height stands out in low latitudes. The time for 500hPa height reaching maximuxn correlation to SST is 2 months later in latitude of 10 degree and 9 months in latitude of 30 degree than equatorial zone. And the response of atmospheric circulation over extratropic performs as wave train, and the response is more significant in the condition of warmer SST. Persistence of SSTs and subtropical highs changes obviously from season to season. Minimum persistence of subtropical highs in September and October may relate to the low persistence of SSTs in August and September.展开更多
基金supported by National Natural Science Foundation of China (49635190).
文摘Based on the reanalysis data of global 500hPa geopotential height (NCEP NCAR CDAS-1) and tropical Pacific SSTs, the characteristics of global subtropical highs and their response to tropical eastern Pacific SST are investigated. Results show that global subtropical highs respond to SST consistently. Subtropical high intensity correlates to the 3 months leading SST maximally. The relationship between SST and 500hPa height stands out in low latitudes. The time for 500hPa height reaching maximuxn correlation to SST is 2 months later in latitude of 10 degree and 9 months in latitude of 30 degree than equatorial zone. And the response of atmospheric circulation over extratropic performs as wave train, and the response is more significant in the condition of warmer SST. Persistence of SSTs and subtropical highs changes obviously from season to season. Minimum persistence of subtropical highs in September and October may relate to the low persistence of SSTs in August and September.