河西走廊东部雷暴灾害时空分布特征及短时临近预报  

Temporal and spatial distribution characteristics and nowcasting of thunderstorm disaster in eastern Hexi Corridor

作　　者：杨晓玲 陈玲 刘蓉 丁文魁 

机构地区：[1]甘肃省武威市气象局,甘肃武威733099 [2]甘肃省永昌县气象局,甘肃永昌733200 [3]甘肃省民勤县气象局,甘肃民勤733300

出　　处：《干旱区地理》2015年第2期223-231,共9页Arid Land Geography

基　　金：科技部行业(气象)专项"农田水分利用效率对气候变化的响应与适应技术"(GYHY201106029);甘肃省干旱气象科学研究基金项目"石羊河流域干旱灾害风险评估及防御对策研究"(IAM201205)共同资助

摘　　要：雷暴天气是河西走廊东部多发的灾害天气之一。利用1961-2013年河西走廊东部5个气象站雷暴资料,运用统计学方法,分析了河西走廊东部雷暴天气的时空分布特征及变化趋势,同时选取1991-2010年4~10月逐日NCEP再分析资料,依据气流的南北配置对雷暴天气进行了环流分型,采用诊断方法、因子组合和日常的经验预报等方法对不同层次、不同物理量进行分析和计算,构建了具有经验性的预报因子库,利用线性相关、经验预报和最大靠近原则等诊断分析方法建立了雷暴天气诊断预报模式。结果表明：受海拔高度和地形地势的影响,河西走廊东部雷暴具有明显的地域特征,南部天祝山区雷暴日数远大于其他各地,占雷暴总日数的40.6%,是河西走廊东部雷暴天气的多发地带。年、年代雷暴日数总体呈减少趋势,天祝的递减趋势尤为显著,年雷暴日数的时间序列存在7~8 a的准周期变化;一年内6~8月是雷暴的高发期,雷暴日数共占年雷暴总日数的70.7%~78.4%。雷暴的日变化特征明显,一日内12~22时为雷暴多发时段,集中发生时段为13~17时,雷暴的平均持续时间为10~40 min。雷暴的环流形势分为三类：西北气流型、西南气流型和西风气流型,其中西北气流型最多。确定了各型雷暴预报模式的预报指标和阈值。诊断模式的预报准确率在75%以上,达到了一定的预报水平,填补了雷暴精细化预报的空白,可为雷暴的业务预报预警以及防雷减灾提供客观有效的指导产品。Thunderstorm is one of the most frequent disaster weather in eastem Hexi corridor. In this paper, us- ing thunderstorm data of five meteorological stations in eastern Hexi corridor during 1961-2013, temporal and spatial distribution characteristics and changing trend of thunderstorm weather were analyzed with statistical methods in eastern Hexi corridor. Besides, the thunderstorm weather circulation pattern were made according to north-south airflow configuration by the daily NCEP reanalysis data spacing at 6 h with the resolution of 1°× 1° from April to October during 1991-2010, different levels and different physical quantities were analyzed and cal- culated using the diagnosis method and factor combination and daily experience forecast method and the empiri- cal prediction factor database was constructed, the diagnostic forecast model of thunderstorm weather was built by diagnostic analysis methods which include linear correlation coefficient, empirical prediction and maximum proximity principle. Results show that： thunderstorm weather varies significantly in different places, thunder- storm days in mountain area of southern Tianzhu is far more than that of other parts, accounting for 40.6% of the total thunderstorm days, southern mountain Tianzhu is thunderstorm prone area of eastern Hexi corridor because of altitude and topography. Annual and age thunderstorm days tend to decrease, decreasing trend is the most sig- nificant in Tianzhu, and decreasing rate is -5.843 d· （10 a）-1. Time series of annual thunderstorm days has six to eight years quasi-periodic variation. Thunderstorm occurred mainly in the period from April to October, the peak period is from June to August in a year, which accounts for 70.7%-78.4% of the annual total thunderstorm days. Additionally, thunderstorm weather varies significantly from time to time in a day, mainly occurring from 12：00 to 22 ： 00, especially concentrating in 13 ： 00 to 17 ： 00, and its average duration is 10-40minutes, the longest dura- tion is 154 min

关 键 词：雷暴 时空分布特征 环流形势 短时临近预报 

分 类 号：P457.9[天文地球—大气科学及气象学]