A Comparison of Physical Parameterization on Tropical Cyclones Simulations Using a Global Non-Hydrostatic Model

Abstract

A non-hydrostatic global model (MPAS) is being implemented in CESM and tested for short-time weather forecasting regime. In this study, tropical cyclone simulations are carried out with two physics suite in MPAS to investigate their role in extreme weather cases. During real-time forecasting, CAM physics package shows comparable results with WRF physics suite in TC track forecasting. However, in CAM-MPAS, there is an intensity bias reflected by a small RMW and strong radial winds in the boundary layer compare to WRF-MPAS. Similar results are also given when we focus on an idealized tropical cyclone test. During this presentation, we will analyze these bias focusing on TC structure and introduce tropical cyclone forecast results using a variable resolution mesh, whose high-resolution has horizontal size of about 15km. At present, a horizontal mesh resolution of around 10km lies in the overlap between global NWP and high-resolution climate experiments. One of main advantage of tropical cyclone simulation using MPAS is capturing meso- or convective scales by linking with synoptic conditions on the globe. Testing and analysis of model results at this resolution is a good step toward seamless prediction.