全球变暖背景下的乌鲁木齐市气温及降水气候特征分析

Changes of Average Air Temperature and Rainfall in Urumqi Under Background of Global Warming

利用乌鲁木齐市1951—2005年逐月平均温度和降水资料,分析了乌鲁木齐市55a来温度和降水的基本气候特征、年代际变化和变化趋势等。结果表明:二维小波系数图可以清楚地显示出气候变化在不同时间尺度上的演变特征,并能对未来的气候演变趋势做出定性估计。小波方差图显示乌鲁木齐市逐月平均气温存在3年为主的短周期和以6年、11—13年为主的长周期;逐月降水存在以3年为主的短周期和以准8年、22年左右为主的长周期。气温和降水在不同时间尺度上的小波系数变化曲线图揭示了气候的长期和短期变化趋势有很大不同。

Using the month- to- month average air temperature and precipitation of Urumqi from 1951 to 2005 ,the basic weather characteristic, interdeeade change and change trends of temperature and rainfall in Urumqi in 55years were analyzed. The results showed that the two - dimensional wavelet coefficient chart could manifest clearly the features of climate variation on different time scales and it could also be used to estimate qualitatively the future tendency of climate. The curves of wavelet variance showed that prominent periods of monthly mean temperature were 3 years ,6 years and 9 years, monthly precipitation had prominent periods of 3 years,8 years and 22 years. The wavelet coefficient curves of temperature and precipitation on different time scales revealed that the long periodical variation trend was quite different from the short.