台灣地區寒潮合成天氣型式之研究

A Study on Composite Synoptic Patterns of Cold Surges near Taiwn

任立渝(Li-Yu Jen) ； 蔡清彥(Ching-Yen Tsay)

《大氣科學》 8卷1期 (1981/05) Pp. 67-79

摘要

本文首先定義台灣地區之寒潮為：「冷鋒通過後，因大陸冷氣團南下，帶來冷空氣，使台北的最低氣溫連續下降兩天達4°C或以上者稱之為寒潮。而下降度數在4°C與5.9°C之間者，稱為中寒潮（M類）；在6.0°C與7.9°C之間者稱為強寒潮（S類）；在8°C或以上者稱為極強寒潮（ES類）」。如最低氣溫只下降一天，而下降溫度達到上述標準者，亦包括在內。為了解各類寒潮天氣型式與結構，本文分別求取各類寒潮在寒潮爆發開始當時，前24小時及48小時的地面、850毫巴、700毫巴及500毫巴之氣壓（或重力位高度）及溫度合成圖。從合成圖中探討寒潮爆發兩天前到當時的天氣型式和變化情形，以及各類寒潮天氣型式之異同。

並列摘要

We first define the Occurrence of a cold surge in Taiwan as the daily minimum temperature at Taipei decreases for 4°C or more in 2 days after the passage of a cold front. If the temperature drop is between 4°C and 5.9°C, we call it a moderate cold surge (type M) ; between 6°C and 7.9°C, a severe cold surge (type S); 8°C or more, an extremely severe cold surge (type ES).To study synoptic patterns and structures of the different types of cold surges, we obtained pressure (or geopotential height)and temperature composite charts of surface, 850mb, 700mb and 500mb at 48, 24 and 0 hours before the passage of cold fronts in northern Taiwan. Synoptic patterns and their time changes as well as the synoptic differences between types of cold surges are discussed.