Abstract:

In order to investigate dry-wet climate change in Urumqi region of Xinjiang, based on the monthly climate data of nine meteorological stations in Urumqi region during 1961-2014, the changing trend, abrupt change characteristics, and the change of spatial distribution before and after abrupt change of various dry-wet climate elements including annual precipitation, potential evapotranspiration (ET0) and dry-wet index, were analyzed by using the methods of linear regression, accumulative anomaly, three-dimensional and quadratic trend surface simulation and inverse-distance square weighting residual error revising based on ArcGIS. The change of dry-wet climate division was studied by combining with the dry-wet climate zoning index. The main results are as follows: A wetting trend was evident in recent 54 years in Urumqi region, generally, annual precipitation and dry-wet index increased significantly with the rate of 11.61 mm·(10 a)-1 and 0.01(10 a)-1, but ET0 decreased obviously with a rate of -13.91 mm·(10 a)-1, and the abrupt change for both of them happened in 1987. In general, annual precipitation and dry-wet index were larger in Tianshan Mountain areas than those in plain areas, while ET0 was larger in plain areas than that in Tianshan mountain areas in Urumqi region. Urumqi region could be divided into 4 dry -wet climate zoning including extremely arid area, arid area, semi-arid area and sub-humid area. The semi-arid area and semi-humid area expanded significantly, but arid area and extremely arid area reduced significantly after 1987 in Urumqi region.

Key words: ArcGIS, precipitation, ET0, dry-wet index, climate division, Urumqi region of Xinjiang

摘要：

为明确气候变化背景下新疆乌鲁木齐地区的干湿气候变化，基于乌鲁木齐地区及其周边9个气象站1961—2014年逐月气候资料，采用线性趋势、累积距平方法以及ArcGIS空间插值技术，在分析年降水量、年潜在蒸散量和年干湿指数的变化趋势、突变特征、突变前后空间分布变化的基础上，结合干湿气候分区指标，探讨了乌鲁木齐地区干湿气候区划的变化。结果表明：近54 a，乌鲁木齐地区年降水量和年干湿指数分别以11.61 mm·（10 a）-1和0.01 （10 a）-1的倾向率显著（P≤0.05）增大， 年潜在蒸散量以-13.91 mm·（10 a）-1的倾向率显著（P≤0.001）减少，且各要素于1987年发生突变。乌鲁木齐地区年降水量和年干湿指数的空间分布表现为“山区多（大）、平原少（小）”的格局，年潜在蒸散量则表现为“山区小、平原大”的特点。乌鲁木齐地区可划分为极干旱区、干旱区、半干旱区和半湿润区4个干湿气候区。1987年后，半干旱区和半湿润区明显扩大，而干旱区明显减小，极端干旱区也有所减小。

关键词:
ArcGIS, 降水量, 潜在蒸散量, 干湿指数, 气候区划, 乌鲁木齐地区