TRMM PR data processing and calibration to be performed by NASDA

The Tropical Rainfall Measuring Mission (TRMM) program is in progress, pushed ahead by NASA and NASDA, along with other related personnel. NASDA is mainly responsible for launching the TRMM observatory, for developing the precipitation radar (PR), and to process the data obtained. NASDA´s data processing, presented in this paper, is mainly for the data of the TRMM PR that is a Japanese-developed rain instrument. the authors are developing the TRMM Data System at the NASDA/Earth Observation Center (EOC) that will be the core of the TRMM operation and data processing in Japan. The EOC TRMM Data System, as well as NASA system, will produce PR Level-1 (Radar received Power, Z-factor), Level-2 (surface σ0, rain qualitative, rainfall rate profile), and Level-3 products (space- and time-averaged rainfall rate) in order. Another important role of NASDA/EOC is to plan and perform external calibration of the PR with ground measurement during the mission so that change of the PR performance can be monitored to compensate measured data. Users may obtain TRMM data products on-line or by media from NASDA/EOC, which would be of great use for the study of the global water and heat cycle and global climate