Bimonthly

ISSN 1006-9585

CN 11-3693/P

+Advanced Search 中文版
Dipole Mode of the Sea Level Pressure Anomalies in Asia-Pacific Region and the Relation to Winter Climate Anomaly in China
Author:
Affiliation:

Fund Project:

  • Article
  • |
  • Figures
  • |
  • Metrics
  • |
  • Reference
  • |
  • Related
  • |
  • Cited by
  • |
  • Materials
    Abstract:

    Using the global monthly mean sea level pressure data, geopotential height, and wind field data as well as the rainfall and temperature data from 160 stations in China, the authors further analyze the temporal variation characters of dipole modes and the relationship between dipole modes and winter climate anomalies in China after studied spatial structure of the sea level pressure anomaly dipole oscillations (dipole modes) over the Asia-Pacific region (20°N-70°N,40°E-120°W) in winter (December to February). The results show that: During the past half century, the winter sea level pressure anomalies (SLPA) over the Asia-Pacific region mainly character with a negative anomalies of meridionaltype dipole mode (ME) and a positive anomalies of zonaltype dipole mode (ZO), while the later one occurrs in a higher frequency. Corresponding to MEmode, there are similarities between geopotential height anomalies and the correlation coefficient distribution of height field and the MEI; on the other side, it takes a consistency feature with a high correlation center over the Aleutian region corresponding to ZOmode, which manifest that the variation of Aleutian Low plays an important role for them. The MEmode is close related to precipitation anomalies and temperature anomalies in the eastern of China in winter. However, because of the relatively weak influence of the ZOmode on the atmospheric circulation anomalies over East Asia, the ZOmode only affected the rainfall anomalies in Northeast China. This result challenges the traditional concerning about the zonal pressure difference (mainly represent ZOmode) in winter and means we should pay more attention to the MEmode. After analyzing of the atmospheric circulation, the authors found that when the MEI is positive anomaly, which means that the pressure field shows a positive anomaly over the northern half of Siberia-Mongolia high and a negative anomaly over subtropical Northwestern Pacific region, this is helpful to enhance and deepen of the East Asia trough, then the East Asian winter monsoon will be stronger, too. However, at this time, the Eastern China region is mainly controlled by sinking air and the warm humid air can not continuously be transported to there, which results in the lack of rainfall over there, especially over the Yangtze River basin. On the contrary, when it is in MEI negative phase, the atmospheric circulation anomaly is conducive to result in a wide range of precipitation in eastern China.

    Reference
    Related
    Cited by
Get Citation

赵巧莲,李崇银.2012.亚洲—太平洋地区冬季海平面气压异常偶极模与我国冬季气候异常的关系[J].气候与环境研究,17(1):1-12. ZHAO Qiaolian, LI Chongyin.2012. Dipole Mode of the Sea Level Pressure Anomalies in Asia-Pacific Region and the Relation to Winter Climate Anomaly in China[J]. Climatic and Environmental Research (in Chinese],17(1):1-12.

Copy
Share
Article Metrics
  • Abstract:
  • PDF:
  • HTML:
  • Cited by:
History
  • Received:
  • Revised:
  • Adopted:
  • Online: February 02,2012
  • Published: