海温对一次上岸对流风暴降水强度影响的数值模拟研究OA

This study conducts a high-resolution numerical simulation and sensitivity experiments on a typi-cal landing convective storm that occurred on 8 August 2022,and investigates the impact of sea surface temperature(SST)variation on the intensity of landing convective precipitation by increasing and decreasing the SST of the Yellow Sea and Bohai Sea.The results show that,compared with the control experiment,the increased SST can enhance the intensity of landing convective precipitation.When SST is raised by 1℃(2℃),the average accumulated precipitation in the coast increases by 2.6 mm(15.7 mm)and the maxi-mum precipitation increases by 38.2 mm(53.7 mm).When SST is lowered by 1℃(2℃),the correspond-ing precipitation decreases by 3.7 mm(8.3 mm),but the maximum precipitation does not show any signif-icant changes.Mechanism analysis indicates that,relative to the control experiment,a rise of 2 ℃ SST sig-nificantly strengthens the coastal boundary layer temperature gradient,wind convergence lifting,as well as the intensity of convective available potential energy and southward-moving cold pools,leading to pro-nounced reinforcement of the front zone at the cold pool leading edge and dynamic lifting.In contrast,a rise of 1℃ SST does not evidently enhance boundary layer wind convergence and southward-moving cold pool intensity,which results in weaker enhancement of the front zone and dynamic lifting than that under the condition of 2℃ SST increase.When SST decreases by 1℃ and 2℃,the mesoscale environmental con-ditions and southward-moving cold pool intensity weaken substantially.The front zone at the cold pool leading edge becomes indistinct,and dynamic lifting is greatly weakened or even transformed into down-drafts,ultimately reducing the intensity of landing convective precipitation.The findings of this paper can provide a theoretical references for the intensity forecasting of landing convective precipitation.