初夏东北冷涡指数的建立与分析(1961-2010)  

Establishment and Analysis of the Early Summer Northeast Cold Vortex Index(1961–2010)

作　　者：何丽烨[1] 马宁[1] 郭军[1] He,L.Y.;Ma,N.;Guo,J.(Tianjin Climate Center,Tianjin 300074,China)

机构地区：[1]天津市气候中心,天津300074

出　　处：《全球变化数据学报（中英文）》2024年第1期104-109,V0104-V0109,共12页Journal of Global Change Data & Discovery

基　　金：中华人民共和国科学技术部(GYHY201506001-1);天津市气象局(201628bsjj01)。

摘　　要：东北冷涡是东亚中高纬度地区的重要天气系统,其频繁活动能够导致明显的气温和降水异常,具有显著的“气候效应”。使用水平分辨率为2.5°×2.5°、时间分辨率为逐日的NCEP/NCAR(美国国家环境预报中心和国家大气研究中心)再分析资料,研究时段取1961–2010年。根据东北冷涡天气学定义,将符合下述条件的天气系统定义为一次冷涡天气过程:(1)在500hPa等压面上至少能分析出一根闭合等高线,并有冷中心或明显冷槽配合的低压环流系统;(2)冷涡中心出现在(35°N–60°N,115°E–145°E)范围内;(3)冷涡在上述地区的生命史为3天或3天以上。考虑海河流域的地理位置,根据逐年东北冷涡低压中心在西涡范围(115°E–125°E)达到的最南位置,界定对初夏(6月,下同)海河流域降水有显著影响的东北冷涡活动关键区域(38°N–48°N,115°E–125°E),统计出冷涡中心频次标准化值,形成初夏东北冷涡指数数据集(1961–2010)。数据集包括:(1)初夏标准化东北冷涡活动指数;(2)逐年初夏东北冷涡500 hPa位势高度低压中心在115°E–125°E区域的最南位置。该数据集存储为1个Excel文件(.xlsx格式),数据量约12.5 KB。The Northeast Cold Vortex(NECV)is a major synoptic system at the mid and high latitudes of East Asia,of which the frequent activities have significant“climate effects”,that may cause temperatures and precipitation anomalies,not just in Northern China,but in the Haihe River Basin(HRB).NECV events were defined if the following three conditions were satisfied in the region of 35°N–60°N,115°E–145°E:first,if a vortex center could be identified at 500 h Pa geopotential height field;second,if a cold trough or a cold center existed around the vortex center at the same pressure level;and third,if the vortex center accompanied with the cold trough or cold core persisted for at least three days.Considering the geographical location of the HRB,a key area(38°N–48°N,115°E–125°E)of the NECV activities closely correlated with early summer precipitation in the HRB was determined by the southernmost locations of the low pressure center at 500 h Pa during the NECV events in the western region of 115°E–125°E year by year.According to the weather conditions of the NECV processes,NECV events were identified using the daily reanalysis data with a horizontal resolution of 2.5°×2.5°came from the NCEP/NCAR(National Centers for Environmental Prediction/National Center for Atmospheric Research),and the early summer NECVI dataset was derived from the standardized frequency of the low pressure center in a key area during the NECV events,spanning from 1961 to 2010.The deposited dataset includes:(1)standardized NECVI in early summer;(2)southernmost locations of the low pressure center at 500 h Pa geopotential height during the NECV events over 115°E–125°E in annual early summer.The dataset is archived in one excel file with data size of 12.5 KB.

关 键 词：东北冷涡 初夏降水 海河流域 气候效应 

分 类 号：P426.6[天文地球—大气科学及气象学] P46