北太平洋爆发性气旋的统计特征  

Statistical Features of Explosive Cyclones over the Northern Pacific

作　　者：张树钦[1] 傅刚[1] 

机构地区：[1]中国海洋大学海洋与大气学院海洋气象系,山东青岛266100

出　　处：《中国海洋大学学报（自然科学版）》2017年第8期13-22,共10页Periodical of Ocean University of China

基　　金：国家自然科学家基金项目(41275049)资助~~

摘　　要：利用FNL(Final Analyses)全球格点资料,对2000—2015年冷季(10月至来年4月)发生于北太平洋(20°N^65°N,110°E^100°W)的爆发性气旋进行了分析研究。依据爆发性气旋的空间分布特征和高时间分辨率的资料,将爆发性气旋定义修订为海表面中心气压(地转调整到45o N)12h平均加深率达到1hPa/h以上的气旋。根据爆发性气旋最大加深率的大小,在强度上将其划分为4类:弱、中、强和超强。日本海、西北太平洋、中西太平洋、中东太平洋和东北太平洋为北太平洋爆发性气旋的5个多发区域,发生于各区域的爆发性气旋依次称之为:JOS(Japan-Okhotsk Sea)、NWP(Northwestern Pacific)、WCP(West-Central Pacific)、ECP(East-Central Pacific)和NEP(Northeastern Pacific)爆发性气旋。北太平洋爆发性气旋发生频数自西向东逐渐减少,呈现出"西多东少"的分布特征。爆发性气旋的统计特征因发生区域不同而呈现出较大差异,NWP爆发性气旋多发生于冬季和早春,而NEP爆发性气旋多发生于秋季和早春;相对于NEP爆发性气旋,NWP爆发性气旋发展较为剧烈,中心最低气压较低,爆发史长和发展史长较长。NWP爆发性气旋的移动路径多为西南-东北向,随着爆发强度的增强,其移动路径更趋于集中。NEP爆发性气旋的移动路径因生成位置的不同而呈现出较大差异,在中西太平洋和中太平洋海域生成的NEP爆发性气旋,其移动路径前期多为偏东向,后期折向西北;而在中东太平洋海域生成的NEP爆发性气旋,其移动路径多为西南-东北向。海洋暖流为NWP和NEP爆发性气旋的急剧发展提供了有利的海洋物理环境场。The climatological features of explosive cyclones （ECs） over the Northern Pacific （20°N^65°N,110°E^100°W） during the recent 15 cold-seasons from October 2000 to April 2015 are analyzed by using Final Operational Global Analysis （FNL） data. According to the meridional distribution of maximum deepening rate position and the temporal resolution of FNL data, the definition of EC is modified into a cyclone whose central sea level pressure decrease normalized at 45°N is greater than 12 hPa within 12 h. These ECs are classified into four categories according to their intensities= weak, moderate, strong and super ECs. Additionally, according to the five high occurrence number centers of the maximum deepe- ning rate position, ECs are further classified into five regions= the Japan-Okhotsk Sea （JOS）, the Northwestern Pacific （NWP）, the West-Central Pacific （WCP）, the East-Central Pacific （ECP）, and the Northeastern Pacific （NEP）. The statistical analyses show that the occurrence number of ECs de- creases eastward over the Northern Pacific. The features of ECs are strongly related to their explosive- developing regions. NWP ECs are most frequent in winter and early spring season, while NEP ECs mainly occur in autumn and early spring season. Comparing with NEP ECs, NWP ECs exhibit stronger intensification rate, lower minimum central sea level pressure, longer developing and explosive-develo- ping lifetimes. The tracks of NWP ECs are typically northeastward direction and their tracks show more uniform characteristics with intensity. The direction of moving tracks for NEP ECs is depended on their formation regions. Those NEP ECs originating from the West-Central Pacific and Central Pacific usually move eastward in early stage and turn to northeastward in later stage. While those NEP ECs forming o- ver the East-Central Pacific usually move northeastward. The warm oceanic current provides favorable environmental conditions for the rapid development of ECs.

关 键 词：北太平洋 爆发性气旋 统计分析 移动路径 

分 类 号：P732[天文地球—海洋科学]