科研进展
科研进展
您的当前位置:首页 > 科研成果 > 科研进展

A decadal abruption of midwinter storm tracks over North Pacific from 1951 to 2010

发布人:ljh  |  来自:本站  |  发布时间:2016-09-04 14:13:47  |  点击次数:964
全文下载连接:http://lageo.iap.ac.cn/uploads/160905061615rs82lbufca9f.pdf
Abstract

Based on 60-year (1951–2010) reanalysis data of the National Oceanic and Atmospheric Administration and extended reconstructed sea surface temperatures, a detailed investigation was conducted to explore the midwinter storm track changes over the North Pacific. The root-mean-square (rms) of subweekly (2.5–6 days) transient of 300 hPa geopotential height field was calculated to represent the storm track. A decadal abruption occurred in 1982/1983, according to the Mann–Kendall test result. The first two Empirical Orthogonal Function (EOF) spatial patterns of the North Pacific storm track during P1 (1955–1982) and P2 (1983–2010) revealed opposite results: The EOF1 during P1 and the EOF2 during P2 revealed changes of intensity of the midwinter storm track in the North Pacific, whereas the EOF2 during P1 and the EOF1 during P2 exhibited a southward/northward shift of its central axis. In addition, pronounced differences in the thermal influence of the ocean on the storm track during P1 and P2 existed. A strong and sustained ENSO signal contributed to a storm track variation through the westerly jet from1955 to 1982, as the storm track was observed to strengthen and shift equatorward during El Niño events. From 1983 to 2010, an apparent sea temperature frontal zone at approximately 40°N and the associated near-surface baroclinicity resulted in the organization of a prominent mid-latitude storm track throughout the depth of the troposphere.
 

摘要

风暴轴作为中纬度天气尺度瞬变涡动最强烈的区域,在中纬度天气和气候系统中扮演着至关重要的角色。本文通过Butterworth带通滤波、EOF分析及合成分析等气象统计方法,探究了1951–2010年北太平洋深冬(1月份)风暴轴的年代际变化及可能影响机制。根据Mann-Kendall突变检验结果,风暴轴在1982/1983左右有明显的年代际突变,突变前后EOF分布基本类似。P1时期(1955–1982年),热带西太平洋强烈且持续的ENSO信号通过西风急流来影响风暴轴,即在厄尔尼诺年间,风暴轴中心强度明显增强且向赤道方向移动,拉尼娜年恰好相反。P2时期(1983–2010年),位于风暴轴入口处的中纬度海洋锋区,由于其南北两侧感热通量的不同,引起局地近地层斜压增长,风暴轴强度增强。

  • 卫星数据中心
  • |
  • 大气物理所
  • |
  • 北京朝阳区华严里40号, 100029 电话:010-82995065,82995091 传真:010-82995073
    版权所有:中国科学院大气物理研究所中层大气和全球环境探测重点实验室
    京ICP备1234556号