Intensity forecast experiment of hurricane Rita (2005) with a cloud-resolving, coupled hurricane-ocean modelling system

A cloud-resolving, coupled hurricane-ocean modelling system is developed under the Earth System Modeling Framework using state-of-the-art numerical forecasting models of the atmosphere and the ocean. With this system, the importance of coupling to an eddy-resolving ocean model and the high resolution of the atmospheric model for the prediction of intensity change of hurricane Rita (2005) is demonstrated through a set of numerical experiments. The erroneous intensification in the uncoupled experiments could be eliminated when taking account of the negative feedback of sea-surface temperature cooling. Moreover, the deepening rate of Rita becomes larger with higher resolution of the atmospheric model. Nevertheless, the horizontal resolution of the atmospheric model with grid spacing at least less than similar to 4 km is required in order to predict the rapid intensity changes of hurricane Rita in the fully coupled experiment. This strong dependence is found to arise from the potential interaction between the ocean coupling and internal processes of Rita, thus indicating that both high resolution and the ocean coupling are indispensable for the future improvement of hurricane intensity prediction. Copyright (C) 2011 Royal Meteorological Society