中国物理B ›› 2014, Vol. 23 ›› Issue (6): 69203-069203.doi: 10.1088/1674-1056/23/6/069203

• GEOPHYSICS, ASTRONOMY, AND ASTROPHYSICS • 上一篇    

The two annual northward jumps of the West Pacific Subtropical High and their relationship with summer rainfall in Eastern China under global warming

叶天舒, 支蓉, 赵俊虎, 龚志强   

  1. College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China
  • 收稿日期:2013-12-27 修回日期:2014-02-16 出版日期:2014-06-15 发布日期:2014-06-15
  • 基金资助:
    Project supported by the National Basic Research Program of China (Grant Nos. 2012CB955902 and 2013CB430204), the National Natural Science Foundation of China (Grant Nos. 41175067 and 41105055), and the Special Scientific Research Fund of Public Welfare Profession of China (Grant No. GYHY201306021).

The two annual northward jumps of the West Pacific Subtropical High and their relationship with summer rainfall in Eastern China under global warming

Ye Tian-Shu (叶天舒), Zhi Rong (支蓉), Zhao Jun-Hu (赵俊虎), Gong Zhi-Qiang (龚志强)   

  1. College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, China
  • Received:2013-12-27 Revised:2014-02-16 Online:2014-06-15 Published:2014-06-15
  • Contact: Zhi Rong E-mail:z_rongphy@cma.gov.cn
  • Supported by:
    Project supported by the National Basic Research Program of China (Grant Nos. 2012CB955902 and 2013CB430204), the National Natural Science Foundation of China (Grant Nos. 41175067 and 41105055), and the Special Scientific Research Fund of Public Welfare Profession of China (Grant No. GYHY201306021).

摘要: The two northward jumps of summer West Pacific Subtropical High (WPSH) are defined based on the pentad-scale ridge data of the WPSH ridge in 1951 to 2012. The times of the northward jumps are found to have obvious inter-annual and decadal characteristics, i.e., the occurrence of the first northward jump of WPSH shows a "consistently early-consistently late" decadal pattern, with the transition around 1980; the occurrence of the second northward jump of WPSH shows a "consistently late-consistently early-consistently late" decadal pattern, with the transitions about 1955 and 1978, respectively, which is consistent with global warming. In the meantime, the times of the two northward jumps not only have a good correspondence to the beginning and ending dates of the rainy season, but also greatly influence the position of the main rain belt in Eastern China. When the first northward jump occurs early, the main rain belt is located from just north of 30° N to the south of North China, while the opposite situation appears when the first jump occurs late. When the second jump occurs early, more rain falls over North China and South China, but less falls in the Yangtze River region, while the opposite situation appears when the second jump occurs late. In the four cases when abnormalities occur in the same year as early or late northward jumps, the position of the main rain belt can be considered as a superposition of isolated abnormal effects of the two northward jumps. Moreover, the prophase and synchronous forces of the sea surface temperature in the Pacific has great influence on the times of the northward jumps, and the driving forces of the two jumps differ.

关键词: northward jumps of WPSH, interannual variation, interdecadal variation, precipitation in Eastern China

Abstract: The two northward jumps of summer West Pacific Subtropical High (WPSH) are defined based on the pentad-scale ridge data of the WPSH ridge in 1951 to 2012. The times of the northward jumps are found to have obvious inter-annual and decadal characteristics, i.e., the occurrence of the first northward jump of WPSH shows a "consistently early-consistently late" decadal pattern, with the transition around 1980; the occurrence of the second northward jump of WPSH shows a "consistently late-consistently early-consistently late" decadal pattern, with the transitions about 1955 and 1978, respectively, which is consistent with global warming. In the meantime, the times of the two northward jumps not only have a good correspondence to the beginning and ending dates of the rainy season, but also greatly influence the position of the main rain belt in Eastern China. When the first northward jump occurs early, the main rain belt is located from just north of 30° N to the south of North China, while the opposite situation appears when the first jump occurs late. When the second jump occurs early, more rain falls over North China and South China, but less falls in the Yangtze River region, while the opposite situation appears when the second jump occurs late. In the four cases when abnormalities occur in the same year as early or late northward jumps, the position of the main rain belt can be considered as a superposition of isolated abnormal effects of the two northward jumps. Moreover, the prophase and synchronous forces of the sea surface temperature in the Pacific has great influence on the times of the northward jumps, and the driving forces of the two jumps differ.

Key words: northward jumps of WPSH, interannual variation, interdecadal variation, precipitation in Eastern China

中图分类号:  (Climatology, climate change and variability)

  • 92.60.Ry