›› 2015, Vol. 24 ›› Issue (4): 49204-049204.doi: 10.1088/1674-1056/24/4/049204

• GEOPHYSICS, ASTRONOMY, AND ASTROPHYSICS • 上一篇    下一篇

Objective identification research on cold vortex and mid-summer rainy periods in Northeast China

龚志强a, 封泰晨b, 房一禾c   

  1. a Laboratory for Climate Studies and Climate Monitoring and Diagnose, National Climate Center, China Meteorological Administration, Beijing 100081, China;
    b Atmosphere and Science College, Luanzhou University, Lanzhou 730000, China;
    c Regional Climate Center of Shenyang, Shenyang 110016, China
  • 收稿日期:2014-08-30 修回日期:2014-10-29 出版日期:2015-04-05 发布日期:2015-04-05
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 41205040 and 41375078), the State Key Development Program for Basic Research, China (Grant No. 2012CB955203), and the Special Scientific Research Project for Public Interest (Grant No. GYHY201306021).

Objective identification research on cold vortex and mid-summer rainy periods in Northeast China

Gong Zhi-Qiang (龚志强)a, Feng Tai-Chen (封泰晨)b, Fang Yi-He (房一禾)c   

  1. a Laboratory for Climate Studies and Climate Monitoring and Diagnose, National Climate Center, China Meteorological Administration, Beijing 100081, China;
    b Atmosphere and Science College, Luanzhou University, Lanzhou 730000, China;
    c Regional Climate Center of Shenyang, Shenyang 110016, China
  • Received:2014-08-30 Revised:2014-10-29 Online:2015-04-05 Published:2015-04-05
  • Contact: Gong Zhi-Qiang E-mail:gzq0929@126.com
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 41205040 and 41375078), the State Key Development Program for Basic Research, China (Grant No. 2012CB955203), and the Special Scientific Research Project for Public Interest (Grant No. GYHY201306021).

摘要: Considering the differences between the Northeast China Cold Vortex (CV) and the Mid-Summer (MS) rainy period and their corresponding atmospheric circulations are comprehensively analyzed, and the objective identification methods of defining the annual beginning and ending dates of Northeast China CV and MS rainy periods are developed respectively. The annual beginning date of the CV (MS) rainy period is as follows. In a period from April to August, if daily regional mean precipitation ryi is larger than yearly regional mean precipitation R (or 2R) on a certain day, the station precipitation rs is larger than the station yearly mean precipitation 〈r〉 (or 2〈r〉) in at least 50% of stations in Northeast China, and this condition is satisfied in the following 2 (7) days, then this date is defined as the beginning date of the CV (MS) rainy period. While the definition of the ending date of the MS rainy period shows the opposite process to its beginning date. With this objective identification method, the multi-year average (1981-2010) beginning date of the CV rainy period is May 3, the beginning date of the MS rainy period is June 27, the ending day of the CV rainy period is defined as the day before the beginning date of the MS rainy period, and the ending date of the MS rainy period is August 29. Meanwhile, corresponding anomaly analysis at a 500-hPa geopotential height, 850-hPa wind, Omega and relative humidity fields all show that the definitions of the average beginning and ending dates of the CV and MS rainy periods have a certain circulation meaning. Furthermore, the daily evolution of the CV index, meridional and zonal wind index, etc. all show that these objectively defined beginning and ending dates of the CV and MS rainy periods have climate significance.

关键词: Northeast China, cold vortex rainy period, mid-summer rain period, objective identification method

Abstract: Considering the differences between the Northeast China Cold Vortex (CV) and the Mid-Summer (MS) rainy period and their corresponding atmospheric circulations are comprehensively analyzed, and the objective identification methods of defining the annual beginning and ending dates of Northeast China CV and MS rainy periods are developed respectively. The annual beginning date of the CV (MS) rainy period is as follows. In a period from April to August, if daily regional mean precipitation ryi is larger than yearly regional mean precipitation R (or 2R) on a certain day, the station precipitation rs is larger than the station yearly mean precipitation 〈r〉 (or 2〈r〉) in at least 50% of stations in Northeast China, and this condition is satisfied in the following 2 (7) days, then this date is defined as the beginning date of the CV (MS) rainy period. While the definition of the ending date of the MS rainy period shows the opposite process to its beginning date. With this objective identification method, the multi-year average (1981-2010) beginning date of the CV rainy period is May 3, the beginning date of the MS rainy period is June 27, the ending day of the CV rainy period is defined as the day before the beginning date of the MS rainy period, and the ending date of the MS rainy period is August 29. Meanwhile, corresponding anomaly analysis at a 500-hPa geopotential height, 850-hPa wind, Omega and relative humidity fields all show that the definitions of the average beginning and ending dates of the CV and MS rainy periods have a certain circulation meaning. Furthermore, the daily evolution of the CV index, meridional and zonal wind index, etc. all show that these objectively defined beginning and ending dates of the CV and MS rainy periods have climate significance.

Key words: Northeast China, cold vortex rainy period, mid-summer rain period, objective identification method

中图分类号:  (Weather analysis and prediction)

  • 92.60.Wc