| 摘要: |
| 利用海温资料、NCEP/NCAR 53 a(1951～2003年)再分析资料和全国160个站的月降水资料,采用小波、合成和相关分析等方法,分析了春季黑潮区域海表温度异常与我国夏季(6～8月)降水及其与夏季500 hPa高度场、水汽输送的关系。结果表明:春季黑潮区域海表温度具有明显的年际和年代际变化特征,海温的增加趋势非常显著,存在不同尺度的周期振荡,其中23 a左右的周期最显著。春季黑潮海温偏高时,中高纬地区的槽和脊加深,西北太平洋副热带高压加强、西伸,导致副热带高压西侧的暖湿气流输送到长江中下游及华南地区,从而使长江中下游及华南地区的夏季降水增多;水汽输送合成场表明来自南海、西太平洋的水汽输送较气候平均年偏强,向长江流域以北的水汽输送减少,使长江中下游及华南地区夏季降水增多;相反,海温偏低时,长江中下游及华南地区的夏季降水减少。 |
| 关键词: 春季黑潮区域海温 中国夏季降水 西太平洋副热带高压 水汽输送 |
| DOI： |
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| 基金项目:国家重点基础研究发展计划项目(2004CB418303);“江苏省研究生培养创新工程”项目(E30000008098-2)共同资助 |
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| RELATION BETWEEN SPRING KUROSHIO SSTA AND SUMMER RAINFALL IN CHINA |
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ZHANG Tian-yu, SUN Zhao-bo, LI Zhong-xian, WANG Dong-yu
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Jiangsu Key Laboratory of Meteorological Disaster, NUIST, Nanjing 210044, China
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| Abstract: |
| Based on the data of SST and NCEP/NCAR reanalysis data, the relationship is analyzed of springSSTA in the Kuroshio region with summer precipitation in China, summer 500 hPa field and water vaportransport, using the methods of Morlet wave, correlation and composite analysis. The results show that annualand interdecadal change of spring SST in the Kuroshio region is distinct. Spring SST displays a significantlyincreasing trend and there exist different periodic oscillations in the Kuroshio region, with the 23-yearperiodic oscillation being the most obvious. Troughs and ridges in the mid- and higher- latitudes turn deeperin high Kuroshio SSTA years. At the same time, the Western Pacific subtropical high strengthens andstretches westwards. As a result, the warm/wet air from the west of the subtropical high locates in the midandlower- reaches of the Yangtze River and south China and summer rainfall in the above regions increasesaccordingly. Composite anomalous water vapor flux fields indicate that the vapor transport from the SouthChina Sea and western Pacific and the vapor from the north converge over the mid- and lower- reaches of theYangtze River and south China, which results in the increase of the summer rainfall in the mid- and lowerreachesof the Yangtze River and south China. On the contrary, the summer rainfall in the mid- and lowerreachesof the Yangtze River and south China decreases correspondently in low Kuroshio SSTA years. |
| Key words: Spring Kuroshio SST summer rainfall in China western Pacific subtropical high water vapor transport |
