Tmi Rain Rate Assimilation Experiment With 4d-var. System For Jma Meso Scale Model
Abstract
The Japan Meteorological Agency (JMA) has been developing four-dimensional vari- ational data assimilation (4D-Var.) system for JMA Meso Scale Model (MSM) to im- prove the initial fields and the forecasts. It will be in operation from early 2002. Con- ventional observations and radar observed precipitation data are hourly assimilated in the system. But these data are obtained only in the vicinity of Japan islands, and it needs to introduce the data obtained apart from there. From this reason, rain rate es- timated by Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) was assimilated in this study, and the impacts for the forecasts were analyzed. In some cases, it shows considerable improvements in the precipitation forecasts. However, TRMM observes our target area only several times per day because of its non-sun- synchronous orbit, and the observation data available for our system is not so much. In the Global Precipitation Measurement (GPM) mission, eight constellation satel- lites with passive microwave radiometers will be operated. The combination of those satellites will provide global precipitation data every three hours. We extremely expect that, in GPM Era, more frequent sampling of accurate precipitation measurements will improve short-range weather forecasting and hazard predictions.
- Publication:
-
EGS General Assembly Conference Abstracts
- Pub Date:
- 2002
- Bibcode:
- 2002EGSGA..27.5142S