干旱区研究 ›› 2011, Vol. 28 ›› Issue (5): 885-890.

• 气候及预报方法 • 上一篇    下一篇

河西走廊东部低温气候特征及预报方法

 丁文魁1,2, 杨晓玲2, 杨金虎3, 周文霞2   

    1. 中国气象局兰州干旱气象研究所 甘肃省干旱气候变化与减灾重点实验室 中国气象局干旱气候变化与减灾重点开放实验室,甘肃 兰州 730020
    2. 甘肃省武威市气象局,甘肃 武威 733000
    3. 甘肃省定西市气象局,甘肃 定西 743000
  • 收稿日期:2010-09-20 修回日期:2010-12-17 出版日期:2011-09-15 发布日期:2011-10-16
  • 作者简介:丁文魁(1970-),男,甘肃古浪人,工程师,主要从事应用气象及研究工作. E- mail: wwqxj6150343@163.com
  • 基金资助:

    甘肃省气象局第五批“十人计划”资助

Study on Climatic Characteristics of Low Temperature in the East Hexi Corridor and Forecast Method

 DING  Wen-Kui1,2, YANG  Xiao-Ling2, YANG  Jin-Hu3, ZHOU  Wen-Xia2   

    1. 1. Lanzhou Institute of Arid Meteorology, China Meteorological Administration, Gansu Province Key Laboratory of  Arid Climatic Change and Disaster Reduction, Key Open Laboratory of Arid Climate Change and Disaster Reduction of China Meteorological Administration, Lanzhou 730020, China
    2. Wuwei Meteorological Bureau, Wuwei 733000, Gansu Province, China
    3.  Dingxi Meteorological Bureau, Dingxi 743000, Gansu Province, China
  • Received:2010-09-20 Revised:2010-12-17 Online:2011-09-15 Published:2011-10-16

摘要: 利用河西走廊东部武威市1960-2009年5个气象站低温(日最低气温≤-20 ℃)资料,系统分析该区低温的时空分布、强度、持续性等气候特征。结果表明:河西走廊东部低温天气具有明显的地域特征,海拔较高的山区和北部沙漠边缘低温日数明显多于绿洲平原区。随着气候变暖,年代、年低温日数明显减少,强度减弱。低温天气主要发生在1月、2月、12月。低温天气具有持续性特征,持续2 d以上的低温次数占总次数的41.4%~64.4%,强低温大多出现在低温持续时段内。同时,运用2003-2007年1月、2月、11月、12月逐日20时ECMWF格点场资料,采用Press准则进行因子初选,逐步回归预报方法进行因子精选,使用最优子集回归建立1月、2月、11月、12月最低气温预报方程,采用CSC双评分准则确定了最低气温预报全局最优的显著性方程,预报方程通过了[WTBX]α=0.01[WTBZ]显著性水平检验。预报方程回代拟合率为70.7%~76.5%,预报准确率为63.5%~68.9%,为低温的业务预报提供了客观有效的指导产品。采用最大靠近原则确定低温预报临界值和低温预报的级别。 

关键词: 低温, 时空分布, 气候特征, ECMWF, 数值预报, 河西走廊

Abstract: In this study, the spatiotemporal distribution, intensity and duration of low temperature in Wuwei in the east Hexi Corridor during the period of 1960-2009 were systematically analyzed using low temperature data (the lowest temperature ≤-20 ℃) observed by 5 meteorological stations. The results show that low temperature occurrence was regional, and low temperature days in high mountains and the marginal zone of north desert were obviously more than those in oases. Days and intensity of low temperature were significantly decreased with climate warming. Low temperature occurred mainly in January, February and December. Proportion of low temperature duration more than 2 days varied in a range of 41.4%-64.4% of the total, and severe low temperature occurred in low temperature process. The factors were initially elected with Press criterion and chosen with stepwise regression forecast method by selecting the ECMWF grid field data in January, February, November and December during the period of 2003-2007, the equations were developed with the optimal subset regression for forecasting the minimum temperature in January, February, November and December. The optimal significance equations for forecasting the minimum temperature were determined with the CSC double grading criterion, and the forecast equations passed through a significance test at level of  α=0.01. Back substitution fitting rate of the prognostic equations varied in a range of 70.7%-76.5%, and the forecast accuracy rate was in a range of 63.5%-68.9%. An objective and effective instruction product was provided for forecasting low temperature. Forecast marginal value and forecast rank of low temperature were determined with the highest approach principle.

Key words: low temperature, climate characteristic, ECMWF, numerical forecast, Hexi Corridor

中图分类号: 

  • P467