摘要:
气候变化对干旱半干旱地区的影响更加显著,为此,需要明确其气候变化趋势,从而为可持续发展提供管理依据。基于152个气象站点1961~2011年降水、温度、风速、湿度和日照时数等气象资料,分析了西北旱区气候的空间分布和变化趋势。近50年,各气象要素的空间分布具有明显的梯度变化特征,最高、最低及平均温度由东南–西北方向表现出增加的趋势,而降水和相对湿度则表现出递减的趋势;在旱区西部南北条带上,日照时数和风速较高,而降水和相对湿度较低。不同要素随时间变化趋势不同,降水和温度多呈上升趋势,而日照时数、相对湿度和风速则多呈下降趋势;变化趋势的显著站点数不同,92%以上站点温度和降水的上升趋势明显,69%站点的风速下降趋势显著,约40%站点的相对湿度和日照时数下降趋势显著;各气象要素基本上都在1980s发生了突变。
Abstract:A more significant impact on arid and semi-arid area from climate change has long been certified. Therefore, it is necessary to be clear about the trend of climate change in arid area of Northwest China, so as to provide management basis for sustainable development. Based on the data from 152 meteorological stations of precipitation, temperature, wind speed, humidity and sunshine hours during 1961 to 2011, the spatial distribution and temporal trends in the arid region of northwest China were analyzed using different methods. In resent 50 years, these meteorological elements on the Arid Northwest spatially distributed with an obvious gradient. Maximum, minimum and mean temperature showed an increasing trend, while precipitation and relative humidity exhibited the trend of decrease from the southeast to the northwest; data showed that, sunshine hours and wind speed were high, while precipitation and relative humidity were low on the north and south strip. Different elements represent different changing trends over time, overall, in investigating years on researching area, precipitation and temperature were mostly on the rise, while sunshine hours, relative humidity and wind speed mostly decreased. The numbers of stations with significant trends for different meteorological elements were quite different. About 92% of stations had significant upward trends in precipitation and temperature, 69% of stations had significantly downward trends in wind speed, and about 40% of stations had significant downward trends in relative humidity and sunshine hours. The meteorological elements basically present abrupt change in the 1980s.