新疆塔城地区年降水与汛期降水时空变化特征及相关分析

Temporal and Spatial Variation Characteristics and Correlation Analysis of Annual Precipitation and Flood Season Precipitation in Tacheng Region of Xinjiang

摘要: 利用近62年(1960~2021年)新疆塔城地区7个气象观测站年降水、汛期(5~9月)降水资料，分别讨论了气候统计特征、时空变化特征，并对其相关性进行分析，结果表明：1) 近62a塔城地区年均降水为234.8 mm，汛期平均降水为120.1 mm，空间分布表现为自北向南逐渐减少，但站点间空间分布差异较大。2) 年降水极值为406.5 mm，汛期降水极值为208.2 mm，均出现于2016年，汛期降水多的年份，年降水也多。3) 年降水、汛期降水年际波动较大，均以偏少为主基调，回归分析表明，年降水以7.49 mm/10a的速率不显著增多(未通过显著性水平检验)，7站年降水均表现为增多趋势，其中裕民、乌苏、沙湾分别以12.03 mm/10a、9.51 mm/10a、7.12 mm/10a的速率显著增多(通过了0.05的显著性水平检验)，区域中仅南部以8.32 mm/10a的速率显著增多(通过了0.05的显著性水平检验)，盆地及中部呈不显著增多趋势；汛期降水以0.12 mm/10a的速率不显著增多，各站均表现为不显著增多趋势，区域中中部增速最大，其次为塔城盆地，最小为南部。4) 年降水、汛期降水标准差分别为53.7、32.9，各站点空间分布差异较大，区域中盆地年降水、汛期降水标准差最大，南部次之，中部最小。5) 年降水、汛期降水变率分别为0.16、0.23，区域中中部年降水变率最大，南部次之，盆地最小，中部及南部汛期降水变率最大，盆地最小。6) 塔城地区年降水、汛期降水、各站点及三个区域降水均表现为中等变异性。7) 年降水经历了“多–少–多–多–多–多”的交替演变，汛期降水经历了“多–少–多–多–少–多”的交替演变，均以21世纪初年最多，1970年代最少，各站年降水，汛期降水年代际分布差异较大。8) 年降水序列在1960年代中末期、1980年代末、1990年代末至2000年代初发生过明显的由多到少和由少到多的突变，突变点为1996年；汛期降水序列在1970年代中期、21世纪初年发生过明显的由多到少和由少到多的突变，1993年为突变点。9) 塔城地区、各站及区域年降水与汛期降水均为显著正相关(通过了0.01的显著性水平检验)，即年降水量多的年份，汛期降水也多。

Abstract: Based on the annual precipitation data and precipitation data in flood season (May-September) of seven meteorological stations in Tacheng region of Xinjiang Province in recent 62 years (1960~ 2021), the statistical characteristics and spatial-temporal variation characteristics of climate were discussed, and the correlation between them was analyzed. The results showed that: 1) The average annual precipitation in Tacheng area was 234.8 mm in recent 62a, and the average precipitation in flood season was 120.1 mm. The spatial distribution showed a gradual decrease from north to south, but the spatial distribution was different among the stations. 2) The maximum annual precipitation is 406.5 mm, and the maximum precipitation in flood season is 208.2 mm, both of which occur in 2016. The years with more precipitation in flood season also have more annual precipitation. 3) The inter-annual fluctuation of annual precipitation and flood season precipitation was large, and the main theme was less. The regression analysis showed that the annual precipitation did not increase significantly at the rate of 7.49 mm/10a (failed to pass the significance level test), and the annual precipitation of the seven stations showed an increasing trend. Among them, Yumin, Wusu and Shawan increased significantly at the rate of 12.03 mm/10a, 9.51 mm/10a and 7.12 mm/10a respectively (passed the significance level test of 0.05), and only the southern part of the region increased significantly at the rate of 8.32 mm/10a (passed the significance level test of 0.05). The basin and the middle part showed no significant increasing trend. The precipitation in flood season did not increase significantly at the rate of 0.12 mm/10a, and all stations showed no signifi-cant increasing trend. In the region, the central part of the precipitation increased the most, fol-lowed by Tacheng Basin, and the southern part was the least. 4) The standard deviations of annual precipitation and flood season precipitation are 53.7 and 32.9, respectively. The spatial distribution of each station is different. The standard deviations of annual precipitation and flood season precip-itation in the central basin are the largest, followed by the southern part and the central part. 5) The annual precipitation variability and the precipitation variability in flood season are 0.16 and 0.23, respectively. The annual precipitation variability is the largest in the central part of the re-gion, followed by the southern part, and the lowest in the basin. 6) The annual precipitation, flood season precipitation, precipitation at each station and the three regions showed moderate variability in Tacheng region. 7) The annual precipitation experienced an alternate evolution of “much-less-much-much-much-much-much-much-much-much-much-much”, and the precipitation in flood season experienced an alternate evolution of “much-less-much- much-less-much”, with the highest annual precipitation in the early 21st century and the lowest in the 1970s. 8) The annual precipitation series had obvious abrupt changes from more to less and from less to more in the midlate 1960s, the late 1980s, the late 1990s to the early 2000s, and the abrupt change point was 1996. The flood season precipitation series had obvious abrupt changes from more to less and from less to more in the mid-1970s and early 21st century, and 1993 was the abrupt point. 9) The annual precipitation of Tacheng region, stations and regions is positively correlated with the precipitation in flood season (passing the significance level test of 0.01), that is, the years with more annual precipitation will also have more precipitation in flood season.