近49a乌鲁木齐气候变化及其与EI Nino/La Nina事件的关系

Study on Climate Change in Urumqi and Its Relationship with EI Nino/La Nina Events in Recent 49 Years

利用乌鲁木齐气象站1961-2009年的逐月平均气温、降水量和风速以及EI Nino/La Nina事件统计数据,采用趋势线法和统计分析等方法,研究近49 a来乌鲁木齐气候变化与EI Nino/La Nina事件的关系。结果表明:49 a来乌鲁木齐降水量和气温均有所增加,风速具有一定的下降趋势;气候向暖湿化方向转变。1961-2009年共有16个厄尔尼诺事件年,13个拉尼娜事件年。EI Nino/La Nina事件影响乌鲁木齐季节降水量、年平均气温和风速。在厄尔尼诺年,乌鲁木齐冬季降水偏少、风速偏小、年平均气温偏高、容易形成暖冬,且易发生旱灾。在拉尼娜事件年,乌鲁木齐春季或夏季往往降水偏多、风速偏大、易遭遇洪水、寒潮和风灾。

In this paper, the methods of trend line and statistical analysis were employed to analyze climate change in Urumqi, Xinjiang and its relationship with the EI Nino/La Nina events based on the data of monthly tem- perature, precipitation and wind speed at Urumqi Meteorological Station and the statistical results of the EI Nino/La Nina events during the period of 1961 -2009. Results indicated that both temperature and precipitation were in- creased, and wind speed was slightly decreased in recent 49 years. Climate changed towards a warming-wetting pattern. The statistical results showed that 16 EI Nino events and 13 La Nina events occurred during the period of 1961 -2009. EI Nino/La Nina events affected seasonal precipitation, annual average temperature and wind speed in Urumqi. In E1 Nino years, winter precipitation in Urumqi was less than that in normal years, wind speed was slightly lower, and the average temperature was slightly higher. It was easy to occur warm winter and drought in Urumqi in the E1 Nino years. Spring and summer precipitation and wind speed were high in Urumqi in the La Nina years, and it was easy to occur flood, cold wave and wind disasters during the La Nina events.