摘要
东北冷涡是影响我国东北地区天气和气候的重要环流系统。本文在前人研究工作基础上,构建了本文的东北冷涡识别与追踪方法。利用2000~2019年NCEP/NCAR再分析资料,对东北冷涡开展客观识别与追踪,进而分析东北冷涡的时空分布特征、持续时间、强度和尺度等,最后利用国家地面气象站小时降水观测数据,探讨了东北冷涡影响期间东北区域的暖季降水分布特征。东北区域内,东北冷涡频数和影响天数无明显长期变化趋势,但存在明显的年际变化和月际变化,东北冷涡更易发生在暖季;东北冷涡的持续时间主要集中在48~72小时,半径尺度范围主要分布在600~1200 km,冷季平均尺度大于暖季,冷季冷涡中心强度也强于暖季;东北冷涡中心活动高频区沿45°~55°N呈东—西走向带状分布;东北冷涡影响期间的暖季降水量占比基本在20%以上,不同强度降水档(0.1~5 mm h^(-1),5~10 mm h^(-1),10~20 mm h^(-1)和≥20 mm h^(-1))中,占比空间分布不同,强降水局地性特征显著;东北冷涡影响期间的暴雨日降水量占比最大可超过70%。
The Northeast China Cold Vortex(NCCV)is a circulation system that significantly affects the weather and climate in northeastern China(NEC).Based on previous studies,a method for identifying and tracking NCCVs is constructed in this study.National Centers for Atmospheric Prediction/National Center for Atmospheric Research reanalysis data from 2000 to 2019 are used to objectively identify and track NCCVs.The temporal and spatial distribution characteristics,duration,intensity,and size of NCCVs are analyzed on this basis,and the relationship between NCCVs and precipitation in NEC during the warm season(May–September)is discussed using the hourly precipitation observation data from 216 national automatic weather stations.NCCVs in NEC have no discernible long-time trend,but there is significant interannual variability and a distinct seasonal variation,which is more likely to occur during the warm season.The duration of NCCVs is generally 48–72 hours,and the size range is mainly distributed in 600–1200 km.The mean size and intensity of NCCVs are both larger in the cold season than in the warm season.The high occurrence of NCCVs presents an east–west zonal distribution along the latitude of 45°–55°N.NCCVs contribute more than 20%of the precipitation in the warm season in NEC.Spatial distribution of precipitation proportion varies in four classes:0.1–5 mm h^(-1),5–10 mm h^(-1),10–20 mm h^(-1),and≥20 mm h^(-1),and the local characteristic of heavy precipitation is remarkable.The maximum contribution of NCCVs to rainstorms can exceed 70%.
作者
黄丽君
崔晓鹏
HUANG Lijun;CUI Xiaopeng(Key Laboratory of Cloud–Precipitation Physics and Severe Storms,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029;Institute of Atmospheric Environment,China Meteorological Administration,Shenyang 110166;Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters,Nanjing University of Information Science&Technology,Nanjing 210044;University of Chinese Academy of Sciences,Beijing 100049)
出处
《大气科学》
CSCD
北大核心
2023年第6期1925-1938,共14页
Chinese Journal of Atmospheric Sciences
基金
中国气象局沈阳大气环境研究所基本科研业务费重点项目2020SYIAEZD4。
关键词
东北冷涡
客观识别与追踪
统计特征
降水
Northeast China Cold Vortex
Objective identification and tracking
Statistical characteristics
Precipitation
