The Prediction Adaptability Comparison Of The Mesoscale Atmosphere-ocean-wave Coupling Model And Its Application In The Typhoon Forecast

Regional mesoscale atmosphere-ocean-wave coupling model can truly reflect the variation regulation of the atmosphere and ocean.It has been widely used in the study of air-sea interaction,but the research of the prediction performance on the Northwest Pacific Ocean is rare,while the sensitivity research on the relevantparameterization scheme is relatively not enough.This paper uses the WRF-ROMS-SWAN regional atmosphere-ocean-wave coupling model via the MCT coupler to carry out a series of numerical experiments on the Northwest Pacific Ocean.We exam the hindcast performance of the coupling model in September 2016 through the comparison of the Final operational global analysis(FNL)data and the results of the simulation experiments.Then we analyze the specific differences of surface atmosphere fields,storm track and intensity,sea surface temperature(SST)and mixing layer temperature between the parameterization scheme MY2.5 and GLS-? in September 2014,which are vertical mixing schemes of ROMS.Finally,typhoon vortex initial technologyis applied in typhoon “FONGWONG” and “MEGI” simulations,and we investigate its influence on the typhoon forecast effect as the reference of operation applications.The main conclusions of this paper are as follows:(1)According to the quantitative analysis of the prediction error of the atmosphere elements field,the prediction error of the coupling model is within the acceptable range,which is better compared with the WRF model.In September 2016,the forecast results of typhoon “MEGI” show that the typhoon track forecast of coupling model is good,but the prediction of strength is weaker due to the lower sea surface temperature caused by the coupling effect.The accuracy ofthe vortex position of the initial field directly affect the forecast effect of the typhoon.(2)In the case of no typhoon weather,the prediction of 2m temperature and 2m relative humidity is better when using GLS-? scheme rather than the MY2.5 scheme.Whileunder the influence of typhoon weather,the MY2.5 scheme outperforms the GLS-? scheme.(3)Different vertical mixing schemes have little influence on typhoon track prediction.The prediction of typhoon track depends mainly on the location of typhoon center and the intensity of typhoon in the initial field.The mixing layer heat content is crucial to the development of typhoon.In the process of ocean response to typhoon,the vertical hybrid caused by the MY2.5 scheme is more intense,resulting in the low mixing layer temperature,which makes the typhoon intensity weak.Therefore,from the point of the disaster warning,it is better using the GLS-? scheme.(4)Vortex relocation scheme can correct the elements fields of the vortex circulation within the range of the background field,under the condition that the large scale environmental field remains the same.Therefore,the coordination and continuity between the vortex circulation and the large scale environment field is maintained after the relocation.We compare the experiments before and after vortex relocation in the simulations of typhoon “FONGWONG” and “MEGI”.It is concludedthat,in the early period,the forecast of typhoon track and intensityis improved greatly when using bogus vortex relocation scheme.