3套资料中西北太平洋热带气旋活动特征的比较分析

本文使用中国气象局、美国联合台风预警中心和日本气象厅的3套热带气旋最佳路径资料(CMA资料、JTWC资料和RSMC资料)分析了1951—2016年西北太平洋热带气旋活动特征。3套资料反映的结果如下:热带气旋主要发生在10°N—25°N范围内,且1980年前其位置点在纬度上有南移的变化趋势,1980年后则相反;移速主要分布在2~6 m/s区间,在25°N左右移速明显加快,1980年前移速呈显著减小趋势;最大持续风速主要分布在10~15 m/s区间,1980年前最大持续风速有减小趋势;在风速较大的区域热带气旋最大风速半径较小,2001—2016年热带气旋和台风最大风速半径每年分别减小0.46 km和0.54 km。CMA和RSMC资料的结果高度一致,而JTWC资料结果与它们都存在一定的差异。热带气旋位置点频数和强度的变化受资料间差异的影响较大,而其位置及移速的变化则受影响较小。

Comparative analysis on the characteristics of tropical-cyclone activities over the western North Pacific in three datasets

The characteristics of tropical-cyclone(TC) activities over the western North Pacific during 1951-2016 were analyzed using three TC best track datasets(CMA, JTWC and RSMC). The consistent conclusions in three datasets are as follows: TCs mainly occurred in the latitude of 10°N-25°N. Before 1980, there was a southward latitude shift of TC position points, while it was the opposite after 1980. The TC translation speed was mostly distributed in the 2~6 m/s, and TCs significantly sped up near 25°N. The TC translation speed had a significant decrease trend before 1980. The maximum wind speed was mainly distributed in the range of 10~15 m/s, and it decreased before 1980. The radius of maximum wind speed was relatively smaller in the region with larger maximum wind speed. The radius of maximum wind speed of TCs and typhoons decreased by 0.46 km and 0.54 km per year respectively during 2001-2016. The results of CMA and RSMC were highly consistent, while the results of JTWC were different from them to some extent. The difference between the three datasets had a great influence on the change of TC intensity and the numbers of position points, but had a little influence on the change of the TC location and translation speed.