积雪初始场对辽宁省冬季气温影响的模拟研究  

Simulation study on the effect of snow cover initial conditions on winter air temperature in Liaoning Province

作　　者：易雪 杨森[1,2,3] 李涛 潘晓 公颖 李得勤[1,2,3] 田莉 YI Xue;YANG Sen;LI Tao;PAN Xiao;GONG Ying;LI Deqin;TIAN Li(Institute of Atmospheric Environment,China Meteorological Administration,Shenyang 110166,China;Shenyang Institute of Agricultural and Ecological Meteorology,Chinese Academy of Meteorological Sciences,Shenyang 110166,China;Key Opening Laboratory for Northeast China Cold Vortex Research,Shenyang 110166,China;College of Statistics,Xi’an University of Finance and Economics,Xi’an 710010,China)

机构地区：[1]中国气象局沈阳大气环境研究所,辽宁沈阳110166 [2]中国气象科学研究院沈阳农业与生态气象研究院(沈阳分院),辽宁沈阳110166 [3]东北冷涡研究重点开放实验室,辽宁沈阳110166 [4]西安财经大学统计学院,陕西西安710010

出　　处：《冰川冻土》2025年第1期111-125,共15页Journal of Glaciology and Geocryology

基　　金：国家重点研发计划项目(2022YFF0801304);辽宁省气象局科研课题(202111,LNCP202305);沈阳大气环境研究所项目(2022SYIAEJY13,2022SYIAEKFMS12)资助。

摘　　要：积雪作为数值模式重要的下垫面之一,尤其是在季节性积雪覆盖地区,其准确性对于积雪表面的地表通量计算以及随后的大气变量模拟至关重要。为检验数值模式中气温模拟对积雪初始场的敏感性,选取辽宁地区2020年1月作为冬季代表月,利用ERA5-Land再分析数据、中国1980—2020年雪水当量25 km逐日产品以及辽宁地区国家级气象观测站的积雪深度和雪水当量数据,分别更新中尺度数值天气预报模式(WRF)的积雪深度和雪水当量初始场,开展积雪初始场对冬季气温影响的模拟试验。结果显示:(1)三套积雪资料均改进了数值模式积雪初始场的正偏差,进而使得日最高气温的冷偏差减小了0.6℃以上,平均气温的冷偏差改进了0.74~0.85℃,最低气温的冷偏差变为暖偏差,对应的平均气温和极端气温的RMSE减小0.38~0.62℃,相关系数增加;(2)受陆面模式中积雪参数化方案的影响,雪水当量初始场的改进要比积雪深度初始场的改进更重要;(3)积雪初始场的改变主要是通过积雪反照率效应影响气温的模拟,而积雪水文效应则较小。Snow cover is one of the important underlying surfaces of numerical models,especially in seasonal snow covered areas,and its accuracy is crucial for the calculation of surface flux and the subsequent predictionof atmospheric variables.Liaoning Province is located in the southern part of Northeast China and is a regionwith seasonal snow cover.The temperature simulations in the Liaoning Province have exhibited a cold bias.Toassess the sensitivity of temperature simulations to initial snow cover fields in numerical models,the WRFv4.1model was utilized,with January 2020 selected as a representative winter month for Liaoning Province.The first24 hours served as the model’s spin-up period,and the simulation results from 00:00 on January 2nd to 23:00on January 31st were analyzed.Four experiments were designed,Control experiment(CTL_Exp):The initialfields of snow depth and snow water equivalent(SWE)in the WRF model were directly provided by the initialand lateral boundary conditions FNL data.Snow initial fields sensitivity experiments:ERA5L_Exp:The initialfields of snow depth and SWE in the WRF model were obtained from the ERA5-Land reanalysis data at 00:00 onJanuary 1,2020.NCDCS_Exp:The initial fields of snow depth and SWE in the WRF model were derived fromthe China 25 km daily snow water equivalent product for the period 1980—2020,using data from January 1,2020.OBS_Exp:The initial fields of snow depth and SWE were interpolated from observations at 62 nationalmeteorological stations in Liaoning Province on January 1,2020.The four experiments are identical except forthe initial conditions of snow depth and snow water equivalent(SWE).The results show that:(1)Enhancingthe accuracy of the initial fields of snow depth and SWE reduced the cold bias in daily maximum,minimum,and mean temperatures.The cold bias of daily mean temperatures simulated by ERA5L_Exp,NCDCS_Exp,and OBS_Exp were improved by 0.74,0.85℃,and 0.8℃respectively compared to CTL_Exp,with an improvement of more than 0.6℃in the cold bias of the daily max

关 键 词：积雪初始场 WRF模式 冬季气温 辽宁省 

分 类 号：P461.6[天文地球—大气科学及气象学]