大气科学2025，Vol.49Issue(2)：337-352,16.DOI:10.3878/j.issn.1006-9895.2308.23075
北亚秋冬季节转换的热力学特征
Thermodynamic Characteristics of Winter Onset in Northern Asia
摘要
Abstract
Using daily reanalysis data obtained from the Japan Meteorological Agency(JRA55)spanning from 1958 to 2020,this study examines the thermal budget characteristics before and after winter onset in Northern Asia(50°-75°N,80°-140°E)as well as the external forces affecting the timing of winter onset.The results show that climatological winter onset in Northern Asia occurs in the 62nd pentad.Before the onset,the region experiences a transition from drastic cooling to a more gradual temperature decline.Diabatic cooling plays a major role during this phase and is partially offset by warm advection.Further analysis based on the linear baroclinic model reveals that diabatic cooling across the middle and high latitudes of the Eurasian continent is conducive to the formation of westerly and southerly winds in Northern Asia.This results in strong local warm advection,which,in turn,partially offsets the effect of diabatic cooling.On an interannual time scale,anomalies in sea surface temperatures in the eastern Equatorial-central Pacific regions and the North Atlantic region affect winter onset in Northern Asia.These anomalies trigger anomalous wave trains across the Eurasian continent,presenting significant signals 1-5 months prior to winter onset,offering potential predictive value.Moreover,the study reveals that some parts of East Asia and southern China experience higher temperatures in December during years when winter onset occurs earlier and lower temperatures during those with a later onset.关键词
北亚/秋冬季节转换/热力收支特征Key words
Northern Asia/Winter onset/Thermodynamic budget characteristics分类
大气科学引用本文复制引用
符诗怡,施宁,周波涛..北亚秋冬季节转换的热力学特征[J].大气科学,2025,49(2):337-352,16.基金项目
国家自然科学基金项目42025502、41975063,江苏省青蓝工程 Funded by National Natural Science Foundation of China(Grants 42025502,41975063),Jiangsu Qing Lan Project （Grants 42025502,41975063）
