| 引用本文: | 郭嘉兵,李金文,马金珠,等.甘肃省1961―2018年降水量时空分布与变化研究[J].灌溉排水学报,2021,(3):142-148. |
| GUO Jiabing,LI Jinwen,MA Jinzhu,et al.甘肃省1961―2018年降水量时空分布与变化研究[J].灌溉排水学报,2021,(3):142-148. |
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| 摘要: |
| 【目的】研究甘肃省降水量时空分布与变化，获得在暖湿趋势下甘肃省降水量变化特征。【方法】选取甘肃省1961―2018年59个气象站降水量为基础数据，采用PCI指数、小波分析、M-K检验等方法对甘肃省降水时空分布特征、降水周期、突变年份及趋势变化进行分析。【结果】甘肃省年降水量在空间上自东向西呈现逐渐减少的规律，降水量年内分配不均匀程度逐渐增加；在时间上，甘肃省存在28、22、12、5 a降水变化周期，其中以28 a周期震荡最强；降水量突变主要发生在20世纪60年代中期、70年代初期、80年代中期以及90年代初期。甘肃省西部地区的降水量整体呈增加趋势，增加率为0.45 mm/a，中部、南部、东部地区呈下降趋势，下降率分别为-0.82、-0.81、-0.93 mm/a。【结论】甘肃省近60 a降水量的长时间尺度周期显著，突变年份与极端降水及干旱事件相对应，西部与中东部地区降水量变化趋势存在较大差异，20世纪90年代后，甘肃省降水量显著增加。 |
| 关键词: 甘肃省；降水量；时空分布；趋势分析 |
| DOI：10.13522/j.cnki.ggps.2020479 |
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| Spatiotemporal Variation in Precipitation over Gansu Province from 1961 to 2018 |
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GUO Jiabing, LI Jinwen, MA Jinzhu*, YU Qiao
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(School of Resources and Environment, Lanzhou University/ Key Laboratory of Western Environment Ministry of Education, Lanzhou 730000, China
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| Abstract: |
| 【Background】Spatiotemporal variation in precipitation is the consequence of a combined impact of regional climate and ecological environment. Global climate change over the past few decades has resulted in a change in precipitation pattern in many regions including Gansu, a province in China characterized by co-existence of arid climate in the west, monsoon climate in the east and alpine climate in the Qinghai-Tibet plateau. This combination makes the ecological and environment systems in Gansu fragile and susceptible to climate change.【Objective】The purpose of this work is to analyze the spatial change in precipitation over the province since 1961 as sell as the underlying mechanisms, especially the impact of global warming and anthropogenic activities.【Method】Precipitation measured from 59 meteorological stations from 1961 to 2018 across the province was analyzed using the PCI index, the wavelet analysis, MK test and other methods, from which we calculated its characteristics including period of precipitation, abnormal changes as well as trends in its spatiotemporal variation using the sliding t test.【Result】The annual precipitation decreased from the east to the west across the province. The intra-annual variation in the precipitation had increased from 1961 to 2018. We identified five periods in the precipitation: 28 years, 22 years, 12 years and 5 years, with the 28 year period most identifiable. Abrupt change in precipitation occurred in the middle 1960s, the early 1970s, the middle 1980s and the early 1990s. Precipitation in the west of the province had been increasing at 0.45 mm/a, while that in the central, south and east parts of the province had been in decline at 0.82 mm/a, 0.81 mm/a and 0.93 mm/a, respectively, until 1990s. But since the 1990s, the precipitation in all regions over the province has been in increase, especially in the east area where the precipitation has been increasing at 3.74 mm/a.【Conclusion】The precipitation in Gansu province over the past 60 years showed periodic and had witnessed both extreme rainfalls and droughts. There is a distinguishable difference in temporal change in precipitation between the west and central-east. Since the 1990s, the precipitation in the province has increased significantly. Our results have important implications for improving ecosystem services and alleviating disasters induced by climate changes, apart from providing a baseline database for meteorological, ecohydrological researches in this region and beyond. |
| Key words: Gansu province; precipitation; spatiotemporal variation; trend analysis |
