Cold Air Mass Analysis of the Record-Breaking Cold Surge Event over East Asia in January 2016

[摘要]  An extreme cold surge event caused record-breaking low temperatures in East Asia during 20-25 January 2016. The planetary- and synoptic-scale feature of the event is investigated quantitatively using the isentropic cold air mass analysis with a threshold potential temperature of 280 K. Because cold air mass is an adiabatically conservative quantity, it is suitable for tracing and examining the extreme cold surges. We further introduced a metric named mean wind of cold air mass, which divides the factor of cold air mass evolution into convergence and advection parts. The new metric allowed us to trace the evolution of the cold air mass with dynamic consistency for a period of more than a week.

[学科分类] 大气科学

[关键词] cold air outbreak;cold air mass;cold surge;East Asian winter monsoon;extreme low temperature