冬季黑潮延伸体异常增暖对东亚夏季风影响的数值试验  

NUMERICAL EXPERIMENT ON THE EFFECT OF THE WARMER SST IN THE KUROSHIO EXTENSION IN WINTER ON THE EAST ASIAN SUMMER MONSOON

作　　者：王晓丹[1,2] 钟中[1] 谭言科[1] 杜楠[3] 

机构地区：[1]解放军理工大学气象学院,江苏南京211101 [2]空军装备研究院,北京100085 [3]成都军区空军气象中心,四川成都610041

出　　处：《热带气象学报》2011年第4期569-576,共8页Journal of Tropical Meteorology

基　　金：国家重点基础研究发展计划项目(2007CB411805);国家自然科学基金项目(40675065)共同资助

摘　　要：利用NCAR CAM3全球大气环流模式数值试验,研究了冬季黑潮延伸体的海温异常增暖对东亚夏季风的影响。结果表明,冬季黑潮延伸体海温异常增暖将导致东亚夏季风增强北推。表征夏季风强度的EASMI(the East Asian Summer Monsoon Index)和LSTDI(the Land-Sea Thernal Difference Index)在夏季风爆发后都呈现了明显的增强趋势,且LSTDI对海温异常增暖的响应更为敏感。华北、南海和菲律宾以东的低空西南季风显著增强,副热带西风急流轴以北(南)西风加强(减弱)。日本群岛及周边海域和中国东部长江以南至秦岭一线的降水明显减少;华北、南海、东海、黄海和菲律宾以东的西太平洋上的降水增多。华北是东亚夏季风对黑潮延伸体的海温异常响应最敏感的区域。东亚地区近地面温度表现为一致的增温特征,而30～50°N之间对流层的整体升温导致了海陆热力差异的加大,这是促使东亚夏季风增强的重要原因。中国及周边地区环流和降水异常分布和西北太平洋副热带高压增强北抬有关。The effect of the warmer SST in the Kuroshio Extension in winter on the East Asian summer monsoon （EASM） is investigated by numerical simulations using global general circulation model NCAR CAM3 . The results show that the anomalous warmer SST in the Kuroshio Extension in winter induces the enhancement and northward advancing of EASM. EASMI and LSTDI that characterize the EASM intensity show significant trend of enhancement after onset of the EASM. Moreover, LSTDI is more sensitive to the warmer SST. The low-level southwesterly monsoon is clearly strengthened in North China, South China Sea and the east of Philippine, while the westerly in the north （south） of the subtropical westerly jet axis is strengthened （weakened）. Precipitation increases distinctly in North China, South China Sea, East China Sea, Yellow Sea and the east of Philippines, however, decreases obviously over Japan islands and adjacent sea area and the areas from the south of Yangtze River to Qinling in East China. North China is the key area most sensitive in the response of EASM to the positive SST anomaly in the Kuroshio Extension. The characteristic of surface air temperature shows consistently a warming trend. The whole rising of troposphere temperature between 30° and 50° enhances the land-sea thermal contrast, which plays an important role in the enhancement of EASM. Circulation and precipitation anomalies in China and its adjacent regions have a close correlation with the enhancement and northward extension of the subtropical high in the Western North Pacific.

关 键 词：气候学 东亚夏季风 数值试验 海温异常增暖 黑潮延伸体 

分 类 号：P435.2[天文地球—大气科学及气象学]