VERIFICATION OF TYPHOON FORECASTS BY THE GRAPES MODEL

【摘要】 Four landfalling typhoon cases in 2005 were selected for a numerical simulation study with the Global/Regional Assimilation and Prediction System(GRAPES) model.The preliminary assessment results of the performance of the model,including the predictions of typhoon track,landfall time,location and intensity,etc.,are presented and the sources of errors are analyzed.The 24-hour distance forecast error of the typhoon center by the model is shown to be about 131 km,while the 48-hour error is 252 km.The model was relatively more skilful at forecasts of landfall time and locations than those of intensity at landfall.On average,the 24-hour forecasts were slightly better than the 48-hour ones.An analysis of data impacts indicates that the assimilation of unconventional observation data is essential for the improvement of the model simulation.The model could also be improved by increasing model resolution to simulate the mesoscale and fine scale systems and by improving methods of terrain refinement processing.更多还原

【Abstract】 Four landfalling typhoon cases in 2005 were selected for a numerical simulation study with the Global/Regional Assimilation and Prediction System(GRAPES) model.The preliminary assessment results of the performance of the model,including the predictions of typhoon track,landfall time,location and intensity,etc.,are presented and the sources of errors are analyzed.The 24-hour distance forecast error of the typhoon center by the model is shown to be about 131 km,while the 48-hour error is 252 km.The model was relatively more skilful at forecasts of landfall time and locations than those of intensity at landfall.On average,the 24-hour forecasts were slightly better than the 48-hour ones.An analysis of data impacts indicates that the assimilation of unconventional observation data is essential for the improvement of the model simulation.The model could also be improved by increasing model resolution to simulate the mesoscale and fine scale systems and by improving methods of terrain refinement processing.更多还原