Variations in extratropical cyclone activity in northern East Asia |
| |
| Authors: | Xinmin Wang Panmao Zhai Cuicui Wang |
| |
| Institution: | Meteorological Observatory in Henan Province, Zhengzhou 450003;Chinese Academy of Meteorological Sciences, Beijing 100081;Chinese Academy of Meteorological Sciences, Beijing 100081 |
| |
| Abstract: | Based on an improved objective cyclone detection and tracking algorithm, decadal variations
in extratropical cyclones in northern East Asia are studied by using the ECMWF 40 Year Reanalysis
(ERA-40) sea-level pressure data during 1958--2001. The results reveal that extratropical cyclone
activity has displayed clear seasonal, interannual, and decadal variability in northern East Asia.
Spring is the season when cyclones occur most frequently. The spatial distribution of extratropical
cyclones shows that cyclones occur mainly within the 40o--50oN latitudinal band in northern
East Asia, and the most frequent region of occurrence is in Mongolia. Furthermore, this study also reveals
the fact that the frequency of extratropical cyclones has significantly decreased in the lower
latitude region of northern East Asia during 1958--2001, but decadal variability has dominated in
higher latitude bands, with frequent cyclone genesis. The intensity of extratropical cyclones has
decreased on an annual and seasonal basis. Variation of the annual number of cyclones in northern
East Asia is associated with the mean intensity of the baroclinic frontal zone, which is influenced
by climate warming in the higher latitudes. Moreover, the dipole structure of extratopical cyclone
change, with increases in the north and decreases in the southern part of northern East Asia, is
related to the northward movement of the baroclinic frontal zone on either side of 110oE. |
| |
| Keywords: | ERA-40 SLP extratropical cyclones variability East Asia cyclone detection and tracking algorithms |
| 本文献已被 CNKI 维普 万方数据 SpringerLink 等数据库收录！ |
| 点击此处可从《大气科学进展》浏览原始摘要信息 |
| 点击此处可从《大气科学进展》下载免费的PDF全文 |
|
