基于多源数据的黄河源区降雪比变化及其影响因素  

Changes in snowfall fraction and the driving factors across headwaters of the Yellow River Basin based on multi-source data

作　　者：宋怡铭 徐世琴 余钟波[3,4] 董宁澎 SONG Yiming;XU Shiqin;YU Zhongbo;DONG Ningpeng(College of Geography and Environmental Science,Northwest Normal University,Lanzhou 730070,China;Hydrology,Agriculture and Land Observation Laboratory,Division of Biological and Environmental Science and Engineering,King Abdullah University of Science and Technology,Thuwal 23955-6900,Saudi Arabia;The National Key Laboratory of Water Disaster Prevention,Hohai University,Nanjing 210098,China;College of Hydrology and Water Resources,Hohai University,Nanjing 210098,China;State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,China Institute of Water Resources and Hydropower Research,Beijing 100038,China)

机构地区：[1]西北师范大学地理与环境科学学院,甘肃兰州730070 [2]Hydrology,Agriculture and Land Observation Laboratory,Division of Biological and Environmental Science and Engineering,King Abdullah University of Science and Technology,Thuwal 23955-6900,Saudi Arabia [3]河海大学水灾害防御全国重点实验室,江苏南京210098 [4]河海大学水文水资源学院,江苏南京210098 [5]中国水利水电科学研究院流域水循环模拟与调控国家重点实验室,北京100038

出　　处：《冰川冻土》2024年第4期1169-1183,共15页Journal of Glaciology and Geocryology

基　　金：国家自然科学基金项目(42101045)资助。

摘　　要：黄河源区是黄河流域关键产流区域,对气候变化十分敏感。在气候变暖背景下,降水形态转变及其影响因素的研究依然不足。围绕这一重要科学问题,本研究基于地面气象站点观测和多源高分辨率气象数据集[China Meteorological Forcing Dataset(CMFD)、ECWMF ERA5-Land(ERA5-Land)、Multi-Source Weather(MSWX)],采用湿球温度参数化模型对1980—2015年黄河源区降水形态进行区分,并对降雪比长期变化趋势及其影响因素进行了综合研究。结果表明,1980—2015年黄河源区降水量整体呈增加趋势,降水形态向降雨转变,降雪量减少,平均降雪比呈显著下降趋势(P<0.05),四套数据源的降雪比平均下降速率为0.002 a^(-1)(P<0.05)。降雪比呈显著下降趋势(P<0.05)的格点占比分别为98.31%(ERA5-Land)、96.87%(MSWX)、67.62%(CMFD)。黄河源区中西部降雪比下降速率较快,下降速率最大的地区为玛多、达日等地。三套格点产品中CMFD能够较好地呈现降雪比变化趋势的空间差异,MSWX次之,而ERA5-Land降雪比变化趋势空间变异较小。源区降雪比与年平均气温、降水量相关性较高(P<0.05),相关系数r分别为-0.42和-0.48,亦受到西风的影响(r=-0.31,P=0.07)。研究结果有助于加深气候变暖对黄河源区水文气象过程影响的科学认识,为黄河流域区域水资源管理提供理论支撑。The headwaters of the Yellow River Basin(HYRB),located in the northeastern part of the Qinghai-Xizang(Tibet)Plateau,serves as the main source of water and is highly sensitive to climate change.However,under the background of climate warming,understanding of shifts in precipitation types and the underlying causes remains limited.This study,focusing on this important scientific issue,utilized a parameterized model of wet-bulb temperature(a precipitation pattern recognition model using surface air temperature,surface pressure,relative humidity and elevation)to differentiate precipitation types across the HYRB from 1980 to 2015.Additionally,we analyzed changes in the annual mean precipitation,rainfall,snowfall and snowfall fraction during this period using the Mann-Kendall test and the Sen’slope estimator.We especially focused on changes in snowfall fraction(SF,defined as snowfall/total precipitation)and analyzed spatial distribution of changes of SF.In order to reduce uncertainty in the differentiation of precipitation patterns by a single product,the analysis is based on weather station observations and multi-source high-resolution meteorological datasets,including the China Meteorological Forcing Dataset(CMFD),t he E CWMF E RA5-Land(ERA5-Land),and the Multi-Source Weather(MSWX).Further,we used the partial correlation analysis to conduct mechanism analyses of the underlying causes of long-term changes in SF in terms of both meteorological and circulation factors,including surface air temperature,relative humidity,precipitation,surface pressure,westerly winds,Indian monsoon,East Asian summer monsoon and ENSO.The results indicate that:(1)Annual mean SF exhibited significant(P<0.05)decreasing trends(0.002 a^(-1)),because there was a decrease in snowfall,but rainfall increased significantly.The precipitation pattern shifted to rainfall.(2)Regionally,the percentage of grids with significant(P<0.05)decreasing trends in SF to the total grids of the HYRB was 98.31%for the ERA5-Land,96.87%for the MSWX,and 67.62%for the CM

关 键 词：黄河源区 降水形态 湿球温度参数化模型 降雪比 气候变化 

分 类 号：P426.63[天文地球—大气科学及气象学]