东亚副热带西风急流变化多模式模拟结果分析  

Multi-model ensemble simulated changes in the subtropical westerly jet over east Asia under the global warming condition

作　　者：张耀存[1] 郭兰丽[1] 

机构地区：[1]南京大学大气科学学院,南京210093

出　　处：《气象科学》2010年第5期694-700,共7页Journal of the Meteorological Sciences

基　　金：公益性行业(气象)科研专项(GYHY200806006)

摘　　要：利用政府间气候变化委员会第四次评估报告(IPCC AR4)中等强度温室气体排放情景试验(SRES A1B)多个耦合模式的输出结果,通过多模式集合的方法分析全球变暖背景下东亚副热带西风急流的变化特征,发现在多模式集合平均结果中,随着温室气体增多、温室效应进一步加剧,冬季急流强度增强,急流位置向北移动,夏季急流强度也呈现出增强的趋势,位置却向南移动。在全球变暖背景下,冬季北半球从低纬到中高纬度对流层中高层温度将增加,但低纬增温强、高纬增温弱,导致副热带地区温度梯度增加,夏季增温幅度比冬季大,且强增温区向北移,造成急流轴北侧区域温度梯度增大,并通过热成风关系使得急流区纬向风增强。The effect of enhanced greenhouse warming on the changes of subtropical westerly jet in location and intensity over east Asia is examined,using the multi-model monthly mean output simulated by coupled climate models participating in the IPCC AR4（Fourth Assessment Report） diagnostic exercise.Results are presented for the A1B scenarios which were produced using a moderate increasing levels of greenhouse gases.For the enhanced greenhouse warming experiments,the muti-model ensemble simulated an intensification in the westerly jet intensity and a northward migration of jet axis in winter,compared with 20th century simulation results.In summer,the westerly jet intensifies and migrates southward.The temperature increase in low latitudes is stronger than that in the high latitudes,leading to an intensification in the meridional temperature gradient in the lower troposphere over subtropical region.This meridional temperature gradient is responsible for the changes in the location and intensity of the westerly jet over east Asia.

关 键 词：东亚副热带西风急流 多模式集合模拟 全球增暖 

分 类 号：P412[天文地球—大气科学及气象学]