ISSN 1006-9895

CN 11-1768/O4

A Numerical Study on the Relationship between the Spring-Winter Snow Cover Anomalies over the Northern and Southern Tibetan Plateau and Summer Precipitation in East China
Author:
Affiliation:

Fund Project:

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

    This study investigates the relationship between the spring-winter snow cover anomalies over the northern and southern Tibetan Plateau (TP) and summer precipitation in East China (EC) based on numerical experiments of CESM (Community Earth System Model). The results show that snow cover anomalies over the southern and northern TP can lead to two patterns of summer precipitation in EC. Larger snow cover in the southern TP leads to excessive rainfall in the Yangtze River basin and northeastern China and less precipitation in southern China; larger snow cover in the northern TP results in enhanced rainfall in northern and northeastern China and less rainfall in the south of the lower reaches of Yangtze River. The possible mechanism of the impacts of snow cover anomalies in the northern and southern TP on summer precipitation in EC is that, changes in the diabatic heating over TP in the summer caused by snow cover anomalies results in weakened temperature gradient and westerly jet on the northern side of TP, and subsequent anomaly of westerly in the exit region. These anomalies further influence the West Pacific Subtropical High (WPSH) in the mid-troposphere and lead to anomalous anticyclonic circulation over EC. Heavier snow cover in the southern TP leads to enhanced westerly jet in the exit region, while heavier snow cover in northern TP results in weakened westerly jet. The degree of the WPSH weakening caused by larger snow cover in the northern TP is greater than that caused by the larger snow cover in southern TP. Thereby the anomalous anticyclonic circulation is located more northward. As a result, the summer rainfall belt shifts northward.

    Reference
    Related
    Cited by
Get Citation
Share
Article Metrics
  • Abstract:
  • PDF:
  • HTML:
  • Cited by:
History
  • Received:January 15,2016
  • Revised:
  • Adopted:
  • Online: March 28,2017
  • Published: