This study examines spatial and temporal changes in 16 extreme temperature indices at 37 weather stations in Xinjiang and their associations with changes in climate means during 1961-2008. Linear regression analyses r...This study examines spatial and temporal changes in 16 extreme temperature indices at 37 weather stations in Xinjiang and their associations with changes in climate means during 1961-2008. Linear regression analyses reveal that significant increas- ing trends in temperature were observed over Xinjiang, with the rate of 0.13 ~C/decade, 0.24 ~C/decade, and 0.52 ~C/decade for annual mean temperature, annual maximum, and minimum temperature, respectively. Annual fi＇equency of cool nights （days） has decreased by -2.45 days/decade （-0.86 days/decade）, whereas the frequency of warm nights （days） has increased by 4.85 days/decade （1.62 days/decade）. Seasonally, the frequencies of summer warm nights and days are changing more rap- idly than the corresponding frequencies for cool nights and days. However, normalization of the extreme and mean series shows that the rate of changes in extreme temperature events are generally less than those of mean temperatures, except for winter cold nights which are changing as rapidly as the winter mean minimum temperatures. These results indicate that there have been seasonally and diurnally asymmetric changes in extreme temperature events relative to recent increases in tempera- ture means in Xinjiang.展开更多
基金funded by a special scientific research project (GYHY200706008) in the public welfare industry (meteorology)the "Western Light" Project (RCPY200902) of the Chinese Academy of Sciencesthe National Natural Science Foundation(41171066) of Xinjiang Institute of Ecology and Geography
文摘This study examines spatial and temporal changes in 16 extreme temperature indices at 37 weather stations in Xinjiang and their associations with changes in climate means during 1961-2008. Linear regression analyses reveal that significant increas- ing trends in temperature were observed over Xinjiang, with the rate of 0.13 ~C/decade, 0.24 ~C/decade, and 0.52 ~C/decade for annual mean temperature, annual maximum, and minimum temperature, respectively. Annual fi＇equency of cool nights （days） has decreased by -2.45 days/decade （-0.86 days/decade）, whereas the frequency of warm nights （days） has increased by 4.85 days/decade （1.62 days/decade）. Seasonally, the frequencies of summer warm nights and days are changing more rap- idly than the corresponding frequencies for cool nights and days. However, normalization of the extreme and mean series shows that the rate of changes in extreme temperature events are generally less than those of mean temperatures, except for winter cold nights which are changing as rapidly as the winter mean minimum temperatures. These results indicate that there have been seasonally and diurnally asymmetric changes in extreme temperature events relative to recent increases in tempera- ture means in Xinjiang.
