西北极端干旱区近54年降水量和温度变化趋势

Variation trends of temperature and precipitation in extremely arid region of northwestern China in recent 54 years

利用西北极端干旱区32个气象站点1960—2013年的月均气温和降水资料,采用线性倾向率法、累积距平法和Mann-Kendall法,研究西北极端干旱区近54年降水量和温度的变化趋势。结果表明:1)54年来,西北极端干旱区平均气温9.3℃,30站表现为显著上升趋势,上升倾向率达到0.034℃/a(P<0.01),且冬季和春季增温幅度大于夏季和秋季,在空间上,西部塔里木盆地为高值区,东南部为低值区;2)西北极端干旱区平均年降水量55.35 mm,29站表现为增加趋势,其中11站通过了0.01水平的显著性检验,倾向率为0.346 mm/a(P<0.01),夏季增加幅度最大,春季最小,在空间上,西北部和东部为高值区、南部为低值区。研究结果表明,近54年西北极端干旱区总体气候呈现明显的暖湿化趋势。

Based on the data from 32 meteorological stations in extremely arid region in northwestern China from 1960 to 2013,we analyzed the characteristics of temperature and precipitation with the methods of the linear regression,cumulative anomaly and Mann-Kendall test. The results indicated that the climate of 30 out of 32 stations in the study region showed a significant trend of warming by 0. 034 ℃ /a（ P〈 0. 01） in recent 54 years with an average annual temperature of 9. 3 ℃. The increases of temperature in winter and spring seasons were higher than those in summer and autumn. Spatially,the highest temperature was found in Tarim Basin,and the lowest in the southeast of the study region. The average annual precipitation（ 55. 35 mm） also showed a significant trend of increasing by 0. 46 mm per10 years（ P〈 0. 01）,and 29 stations presented such trend,of which 11 passed the significant test. The highest rate of increase was found in summer,and the lowest in spring. The northwest and east part had higher precipitation than the south part of the study region. In general,the climate in the recent 54 years tended to be warmer and wetter.