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Ji, Yimin

Publications and source records attributed to Ji, Yimin.

TRMM Microwave Imager (TMI) Updates for Final Data Version Release

The Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) dataset released by the Precipitation Processing System (PPS) will be updated to a final version within the next year. These updates are based on increased knowledge in recent years of radiometer calibration and sensor performance issues. In particular, the Global Precipitation Measurement (GPM) Microwave Imager (GMI) is used as a model for many of the TMI version updates. This paper discusses four aspects of the TMI data product that will be improved: spacecraft attitude, calibration and quality control, along-scan bias corrections, and sensor pointing accuracy. These updates will be incorporated into the final TMI data version, improving the quality of the data product and ensuring accurate geophysical parameters can be derived from TMI.

Tropical Rainfall Measuring Mission↗

Incorporating the TRMM Dataset into the GPM Mission Data Suite

In June 2015 the TRMM satellite came to its end. The 17 plus year of mission data that it provided has proven a valuable asset to a variety of science communities. This 17plus year data set does not, however, stagnate with the end of the mission itself. NASA/JAXA intend to integrate the TRMM data set into the data suite of the GPM mission. This will ensure the creation of a consistent, intercalibrated, accurate dataset within GPM that extends back to November of 1998. This paper describes the plans for incorporating the TRMM 17plus year data into the GPM data suite. These plans call for using GPM algorithms for both radiometer and radar to reprocess TRMM data as well as intercalibrating partner radiometers using GPM intercalibration techniques. This reprocessing will mean changes in content, logical format and physical format as well as improved geolocation, sensor corrections and retrieval techniques.

TRMM↗

GPM Data Products, Their Availability, and Production Status

On February 28, 2014, Japan Standard Time, the Global Precipitation Measurement (GPM) mission was launched in a picture-perfect launch activity. On March 4, 2014, the GPM Microwave Imager (GMI) was put into science observation mode. The Dual-Frequency Radar (DPR) was put in science observation mode on March 8, 2014. The Precipitation Processing System (PPS) produced products immediately upon receiving the data. Both regular science products and Near-realtime (NRT) products were produced. These were made immediately available to a group of early adopters. In mid-June 2014, GMI level-1 brightness temperature products were made publicly available. In mid-July 2014, GMI and partner-radiometer precipitation retrievals were made public. GMI public availability was several months ahead of the planned release. The DPR products became publicly available on the planned release date of September 2, 2014. Data continues to be available to any user desiring it.

Data Products↗