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TRMM Precipitation Radar Power and Reflectivity L1B 1.5 hours V7 (TRMM_1B21) at GES DISC

Metadata Updated: December 6, 2023

The TRMM Precipitation Radar (PR), the first of its kind in space, is an electronically scanning radar, operating at 13.8 GHz that measures the 3-D rainfall distribution over both land and ocean, and defines the layer depth of the precipitation.

The 1B21 calculates the received power at the PR receiver input point from the Level-0 count value which is linearly proportional to the logarithm of the PR receiver output power. To convert the count value to the input power, extensive internal calibrations are applied, which are mainly based upon the system model, temperature dependence of model parameters and many temperature sensors attached at various locations of the PR. Periodically the input-output characteristics are measured using an internal calibration loop for the IF unit and later receiver stages. To make an absolute calibration, an Active Radar Calibrator (ARC) is placed at Kansai Branch of CRL and overall system gain of the PR is being measured every 2 months. Using the transfer function based on the above internal and external calibrations, the PR received power is obtained. Note that the value assumes that the signal follows the Rayleigh fading, so if the fading characteristics of a scatter is different, a small bias error may occur (within 1 or 2 dB).

Changes in horizontal resolution resulting from the TRMM boost that occurred on 24 August 2001:

Pre-Boost (before 7 August 2001): Temporal Resolution: 91.5 min/orbit ~ 16 orbits/day; Swath Width: 215 km; Horizontal Resolution: 4.3 km

Post-Boost (after 24 August 2001): Temporal Resolution: 92.5 min/orbit ~ 16 orbits/day; Swath Width: 247 km; Horizontal Resolution: 5.0 km

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Created Date November 12, 2020
Metadata Updated Date December 6, 2023

Metadata Source

Harvested from NASA Data.json

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Additional Metadata

Resource Type Dataset
Metadata Created Date November 12, 2020
Metadata Updated Date December 6, 2023
Identifier C1282110505-GES_DISC
Data First Published 2011-07-01
Language en-US
Data Last Modified 2016-04-20
Category TRMM, geospatial
Public Access Level public
Bureau Code 026:00
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Citation Tropical Rainfall Measuring Mission (TRMM). 2011-07-01. TRMM_1B21. TRMM Precipitation Radar Power and Reflectivity L1B 1.5 hours V7. Greenbelt, MD. Archived by National Aeronautics and Space Administration, U.S. Government, Goddard Earth Sciences Data and Information Services Center (GES DISC).
Creator Tropical Rainfall Measuring Mission (TRMM)
Graphic Preview File
Harvest Object Id 2b536af9-0644-4860-9811-15737b5580cc
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL
Metadata Type geospatial
Old Spatial -180.0 -38.0 180.0 38.0
Program Code 026:001
Release Place Greenbelt, MD
Series Name TRMM_1B21
Source Datajson Identifier True
Source Hash 798735c5c7b116bb8c448ad560beaeda4723bd5a57a5ff37ec73c54f577e8340
Source Schema Version 1.1
Temporal 1997-12-07T00:00:00Z/2015-04-01T23:59:59.999Z

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