The diagnosis of CWB model forecast by using Community Radiative Transfer Model

The applications of atmospheric satellite remote sensing data include earth radiation budget monitoring and climate projection, air quality detection, numerical weather prediction (NWP) and other researches related to earth science. Focus on NWP and climate projection, the satellite instruments provide near-global coverage observations that not only would benefit the performance of weather forecast and climate prediction but also could be used for model evaluation. This study uses the Community Radiative Transfer Model (CRTM) to simulate the satellite-observed radiance at the top-of-atmosphere (TOA) by the NWP model outputs from Taiwan Central Weather Bureau (CWB) global model forecast. The European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis datasets will be used as the reference. Therefore, the brightness temperature difference (BTD) between model and observation in two window channels (11 and 12) of Moderate Resolution Imaging Spectroradiometer (MODIS) onboard Terra/Aqua will be analyzed to help the evaluation of CWB global model forecast. The preliminary result indicates that both CWB's initial forecast and MODIS BTDs are less than 1 K. However, MODIS's shows some noise which could be caused by the high spatial resolution or the cloud contamination in the clear sky pixels. The efforts will continue to diagnose the long-term BTD datasets at different forecast time and quantify the model performance in the future.