摘要
2018年1月中国东部季风区发生异常的降雪分布及局地的雨雪冰冻灾害。在分析东部季风区降雪时空分布特征的基础上,模拟典型站点的气团移动轨迹,并利用OLR数据研究水汽源区变化及输送过程对降雪异常的影响。结果表明:1月降雪主要分布在黄河以南地区,降雪范围内呈现出降雪量由南向北降低的规律,且降雪持续时间减小;西北方向西风带混合输送与南向水汽源区及近源局地水汽循环是降雪区主要的水汽来源,随着水汽移动轨迹的变化,降雪的空间分布也随之改变;水汽源区的变化状况通过对水汽输送通量及路径的改变,进而决定着东部季风区降雪量与时空分布特征,2018年1月水汽源区表现出明显La Nina年特征,并与气团的移动轨迹相吻合,La Nina事件应是导致降雪异常的深层次原因。
The abnormal distribution of snowfall and disaster of snow storm and frozen rain occurred in the monsoon region of the East China in January,2018.By analyzing the temporal and spatial distribution characteristics,this paper simulated the trajectory of the air mass at a typical site and studied the influence of water vapor source area and transportation process to the anomaly snow by OLR technology.The results show that the snowfall is mainly distributed in the south of the Yellow River,the snowfall and its duration decreased from the south to the north in the snowfall area.The westerly mixes transport in northwestern direction,southern water vapor source and the near source local circulation of water vapor are the main sources of water vapor in the snowfall area.The track of water vapor migration varies with the spatial distribution of snowfall.The change of water vapor source area determines the quantity and spatio-temporal distribution of snowfall in the eastern monsoon region by changing the flux and path of water vapor.Moreover,the water vapor source area performs obvious feature of La Nina event and is consistent with the migration trajectory of the air mass,which shows that the La Nina event should be the deep cause of abnormal snowfall.
作者
郭政昇
曹富强
郑国璋
GUO Zhengsheng;CAO Fuqiang;ZHENG Guozhang(College of Geographical Sciences,Shanxi Normal University,Linfen 041004,China)
出处
《水文》
CSCD
北大核心
2020年第1期81-85,51,共6页
Journal of China Hydrology
基金
山西师范大学科技开发与应用基金项目(ZK1402)
