Upper-air temperature change trends above arid region of Northwest China during 1960–2009

题名：Upper-air temperature change trends above arid region of Northwest China during 1960–2009
领域：METEOROLOGY & ATMOSPHERIC SCIENCES 三区
来源：Theoretical and Applied Climatology

发表年代：2014年
作者：Zhongsheng Chen, Yaning Chen, Jianhua Xu (徐建华）, 等

This study summarized upper-air temperature change trends based on the monthly datasets of 14 sounding stations in the arid region of Northwest China during 1960–2009. Over the investigated period, the change in upper-air temperature measured at eight standard pressure levels shows that an obvious warming at 850–400 hPa, which decreases
with altitude, changes to an apparent cooling at 300–50 hPa. There is a positive correlation between the surface and 850–300-hPa temperatures, but a negative correlation between the surface and 200–50-hPa temperatures. Over the full 1960–2009 record, patterns of statistically significant mid-lower tropospheric warming and upper tropospheric and mid-lower stratospheric cooling are clearly evident. Also, the annual temperature cycle indicates that the peak temperature shifts from July in the troposphere to February in the mid-lower stratosphere, suggesting the importance of seasonal trend analysis. We found that the warming in the mid-lower troposphere is more pronounced during the summer, autumn, and winter, whereas the cooling in the upper troposphere and midlower stratosphere is larger during the summer and autumn. Furthermore, there are also many regional differences in the upper-air temperature change, regardless of both season and layer.