基于WRF_Lake模拟的鄱阳湖对局地夏季降水的影响

Influence of Poyanghu Lake on Local Precipitation in Summer Based on WRF Lake Model Simulation

利用耦合湖泊模型的区域气候模型WRF,综合分析了鄱阳湖对局地夏季降水的影响。首先利用气象站点数据和MODIS卫星数据评估了耦合湖泊模型的WRF模型(WRF_Lake)在鄱阳湖的适用性,并在此基础上进行去湖敏感性模拟试验。结果表明,WRF_Lake模型可准确地模拟鄱阳湖区的湖表面温度、2m气温、降水发生的时间和降水空间分布;不同时间段,鄱阳湖对湖区降水的作用具有差异性,6月鄱阳湖表现为促进降水的正效应,可增加湖面25%~35%的降水,而7、8月表现为抑制作用的负效应,分别抑制了湖面15%~35%和15%~25%的降水;不同时间段,鄱阳湖对研究区(27.75°N^30°N,115°E^117.5°E)降水的作用具有差异性,6、7月可分别增加研究区1.5%、3.4%的降水,8月则表现出抑制降水的作用。

The regional climate model WRF coupled lake model was used to comprehensively analyze the impact of Poyanghu Lake on the local summer precipitation.Firstly,the meteorological site data and MODIS satellite data were used to evaluate the applicability of the WRF model coupled lake model in Poyanghu Lake area,and then the sensitivity simulation tests of lake removal were carried out.The results show that the WRF_Lake model can accurately simulate the lake surface temperature,2 mair temperature,the frequency of precipitation,and spatial distribution of precipitation over the Poyanghu Lake region during the summer;The influence of Poyanghu Lake on precipitation over the lake area changes with different time.In June,Poyanghu Lake has a positive effect of promoting precipitation,and increases precipitation by 25%-35% over the lake;But it has a negative effect in July and August,and inhibited 15%-35%and 15%-25% precipitation respectively over the lake.The influence of Poyanghu Lake on precipitation over the whole study area(27.75°N-30°N,115°E-117.5°E)changes with different time.In June and July,the precipitation in the area increased by 1.5% and 3.4%respectively.In August,it shows the effect of inhibiting precipitation.