西北太平洋热带气旋对东亚大气环流的影响

使用1960-2015年6-10月上海台风研究所(CMA-STI)整编的热带气旋最佳路径数据集和NCEP/NCAR再分析资料,借助相关性分析、典型相关分析、耦合场分离方法等统计学方法研究了热带气旋对东亚大气环流的影响。主要结论如下:热带气旋活动增强使得对流层高层温度增加,低层温度降低;对位势高度场的影响主要是使得位势高度降低,最大的影响区在500 hPa;分析东亚大气环流与热带气旋之间的耦合相互作用发现,大气环流和热带气旋相互反馈作用较强的区域往往也是热带气旋对大气环流独立影响较强的区域。两者相互耦合影响部分的解释方差(4%~7%)明显小于单方面由热带气旋引起的大气环流变化部分的解释方差(12%~18%)。

Effects of tropical cyclone in the Northwest Pacific on East Asian atmospheric circulation

Based on the CMA-STI tropical cyclone best track data and NCEP/NCAR reanalysis data between July and October from 1960 to 2015,statistical approaches such as correlation analysis,canonical correlation analysis and coupled field separation methods were used to study the effects of tropical cyclones on East Asian atmospheric circulation.The main conclusions are summarized as follows.The increase of tropical cyclone activity increased the temperature of the upper troposphere and decreased the temperature of the lower layer.The influence on the geopotential height field is that the height of the potential is reduced.The largest affected area is at 500 hPa.The coupling interaction between East Asian atmospheric circulation and the tropical cyclone suggests that the regions with the strong mutual feedback between atmospheric circulation and the tropical cyclone are also the regions where the tropical cyclone have strong independent influences on the atmospheric circulation.The explanation variance(4%—7%)of the mutual coupling effect is significantly less than the explanation variance(12%—18%)of the atmospheric circulation changes caused by the unilateral forced by tropical cyclone.