Evaluation of Two Microphysics and Radiation Schemes in HWRF Using Remote Sensing Data

The goal of this study is to evaluate Hurricane Weather Research and Forecasting model (HWRF) microphysics/radiation scheme’s skill in realistically simulating hurricane clouds, focusing on the current operational Ferrier/GFDL and the alternative Thompson/RRTMG. The objective of this study is to quantitatively compare the HWRF forecast microphysics hydrometeors and cloud brightness temperature against those observed by remote sensing satellite. This study will identify and compare the deviations of the Ferrier/GFDL and Thompson/RRTMG schemes from the remote-sensing observations. The result of this study could also potentially help the diagnosis of the other parts of HWRF as well; therefore help identify avenues to improve the model’s forecast skills. 

In this study, we used the brightness temperature in the infrared channel (band-4) data measured by the Geostationary Operational Environmental Satellite (GOES) operated by the United States National Environmental Satellite, Data, and Information Service (NESDIS). Dr. Greg Thompson recommended the use of the infrared channel brightness temperature data because it can best represent the cloud-top temperature without interference due to diurnal variations in other channels.

The observed GOES satellite data were obtained from the online archive at NOAA’s Comprehensive Large Array-Data Stewardship System (CLASS) at http://www.class.ngdc.noaa.gov.  Due to the large size of the global data, we only retrieved the data within a fixed sub-set that covers the majority areas of both the AL and EP basins where most hurricanes occur (Fig. 1). 

Figure 1. An example (for October 17th, 2014) of the retrieved GOES infrared channel brightness temperature data from NOAA’s CLASS system.  All the GOES data retrieval used the same domain grid.