民國九十年臺灣地區氣候變化與農業氣象災害

Abstract

夲文之目的在概述民國九十年臺灣地區之氣候況及農業氣象災害全年影響臺地區的天氣系統有鋒面、東北李大陸冷氣、華南雲雨偏東移、風(含其外圍環流)、熱帶性低氣、低壓帶及西南氣流等，其中有3次寒流伴隨鋒面南下影響灣。全年年均氣溫匾髙溫且冬季偏瑗炎B數除臺北及花蓮兩氣象站多氣候平均值為正距平外，其他地方平或少於平均;寒冷日數則遠少氣候値，為造成全年平均氣匾髙的重要因素。全年年雨量屬多，雨量大部分來自於9月颱風所帶來的貢獻。豪大雨發生日數最多的月份亦集中9月民國九十年有26颱風生成與氣候相近;但其中有7個侵臺颱風，屬多侵臺颱風年，侵臺颱風中尤以納莉颱風之路徑最怪異且創下某些氣象站雨量紀錄。全年因氣象災害造烕之農作物損失金額約新臺幣47億多元，以颱危害最大，其中尤以桃芝及納莉颱風所造成的災害損失最爲嚴重。 The purpose of this paper is to describe the climatic situations and agrometeorological disasters occurred in Taiwan in 2001. The main systems affected Taiwan's weather including front, northeasterly monsoon, continental cold air-mass, easterly moving rainbelt from southern China, typhoon, tropical depression, belt of low pressure and southwesterly now, etc. Three cold waves associated with the front occurred this year. Annual mean air temperature was higher than the average, and resulted in a warmer winter. The numbers of hot-day in 2001, except that in Taipei and Hualien weather stations, were less than normal, but the numbers of cold-day were far less than normal. The decrease of cold days implied that it was an important factor caused high temperature in 2001. Annual rainfall was much higher than normal. Most rainfall was contributed by the typhoon in September. The days of heavy rainfall occurred mostly in September too. Twenty-six typhoons were formed on the northwestern Pacific in 2001, equal to normal. Seven typhoons attacked Taiwan, much more than normal. Among them, the path of Nari was weird and unexpected. It made a long stay, over forty-nine hours, on Taiwan and a record rainfall at some weather stations. The accumulated total loss in crop exceeded forty-seven thousand million NT dollars. The damage caused by typhoon was the most severe among all weather disasters, and the Toraji and Nari typhoons brought the most loss than other typhoons in 2001.