青藏高原冬季降雪特征及相关环流分析  

Snowfall Characteristics in Winter over Qinghai-Xizang(Tibetan)Plateau and Its Key Circulation

作　　者：申红艳 乔少博 封国林[4] 龚志强[4] 温婷婷 冯晓莉 SHEN Hongyan;QIAO Shaobo;FENG Guolin;GONG Zhiqiang;WEN Tingting;FENG Xiaoli(Meteorological Institute of Shaanxi Province,Xi’an 710016,Shaanxi,China;Key Laboratory of Eco-Environment and Meteorology for the Qinling Mountains and Loess Plateau,Shaanxi Meteorological Bureau,Xi’an 710016,Shaanxi,China;School of Atmospheric Sciences,Sun Yat-sen University,Zhuhai 519082,Guangdong,China;China Meteorological Administration,Beijing 100081,China;Qinghai Climate Center,Xining 810001,Qinghai,China)

机构地区：[1]陕西省气象科学研究所,陕西西安710014 [2]陕西省气象局秦岭和黄土高原生态环境气象重点实验室,陕西西安710014 [3]中山大学大气科学学院,广东珠海519000 [4]中国气象局,北京100081 [5]青海省气候中心,青海西宁810001

出　　处：《高原气象》2024年第4期841-854,共14页Plateau Meteorology

基　　金：国家自然科学基金项目(42065003);陕西省科技厅自然科学基础研究计划项目(2023-JC-YB-252)。

摘　　要：利用1961-2020年青藏高原降雪观测资料和大气再分析数据,分析了高原冬季降雪特征及其关键环流系统。结果表明:高原冬季降雪空间分布不均,表现为西北少、东南多,同时降雪年际振荡和年代际变化特征明显,1988年发生由偏少向偏多的转折。青藏高原冬季降雪一致偏多时,中高纬呈现类似欧亚南部型(Southern Eurasian,SEA)遥相关的正位相特征,即欧洲西南部、阿拉伯海、东北亚上空位势高度场为显著正异常,中东地区、青藏高原上空为显著负异常,经分析发现,SEA正位相时中东急流增强,高原南部上升运动明显,高原东北部和西南侧出现水汽显著辐合区,为青藏高原冬季降雪异常偏多提供有利条件。与此同时,北大西洋涛动(North Atlantic Oscillation,NAO)正(负)位相时有利于青藏高原降雪偏多(少),NAO主要通过SEA型遥相关和中东急流等环流系统来调控高原冬季降雪。Based on the meteorological observational data over Qinghai-Xizang(Tibetan)Plateau and atmospheric reanalysis dataset during 1961 to 2020,the snowfall variation characteristics over the Qinghai-Xizang(Tibetan)Plateau and its related corresponding circulation system were analyzed in this paper.Main conclusions are drawn as following:the spatial distribution of snowfall shows a uniformity with less in the northwest and more in the southeast.The characteristics of interannual and interdecadal variability are very evident.The interannual variability of the snowfall over Qinghai-Xizang Plateau was strong.The first mode of Qinghai-Xizang(Tibetan)Plateau snowfall anomalies is regional uniformity.In terms of the key circulation systems that affect Qinghai-Xizang(Tibetan)Plateau snowfall,when the snowfall over Qinghai-Xizang(Tibetan)Tibetan Plateau is more,the upper troposphere corresponds to the positive phase of the southern Eurasian(SEA)teleconnection,characterized as positive anomalies over the southwestern Europe,the Arabian Sea,and the northeast Asia,and negative anomalies over the Middle East and the Qinghai-Xizang(Tibetan)Plateau,while the Middle East jet is stronger;the positive(negative)phase of North Atlantic Oscillation(NAO)is conducive to more(less)snowfall over Tibetan Plateau,via modulating the SEA teleconnection and key circulation systems such as the Middle East jet stream.

关 键 词：青藏高原 降雪 年际变化 环流异常 

分 类 号：P426.61[天文地球—大气科学及气象学]