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    • Chang SSM/I Derived Monthly Rain Indices 5 x 5 degree V2.3 (RAIN_CHANG) at GES DISC

    Metadata Updated: April 11, 2025

    These data are transitioned to a state of permanent preservation. They are available upon request. More advanced datasets have been developed since. One recommended replacement is the GPCP (doi: 10.5067/DBVUO4KQHXTK) product developed under the MEaSUREs project.

    Futhermore, the NASA Precipitation Measurement Missions Project released newly processed SSM/I datasets as output from the GPROF (Goddard Profiling Algorithm). (doi: 10.5067/GPM/SSMI/F11/GPROFCLIM/2A/05, 10.5067/GPM/SSMI/F11/GPROFCLIM/3A-MONTH/05, 10.5067/GPM/SSMI/F11/GPROFCLIM/3A-DAY/05)

    The "RAIN_CHANG" SSM/I Derived Oceanic Monthly Rainfall Indices data set was an early Global Precipitation Climatology Project (GPCP) product. Monthly rainfall indices over the oceans were derived from Special Sensor Microwave Imager (SSM/I) data from the Defense Meteorological Satellite Program (DMSP) satellites F8 and F11, on channels 19 and 22 V. The data set covered the period from July 1987 to December 1995.

      The monthly rainfall indices are on a 5 degree by 5 degree grid extending from 50 N to 50 S. The Wilheit, Chang and Chiu (1991) method used to derive the indices gives valid values only over ocean areas. Land pixels (including island pixels) and erroneous pixels return a -10 flag. The data are stored on a 72 x 20 grid. Grid point (1,1) contains the index for 45-50 N, 0-5 E, grid point (2,1) contains the index for 45-50 N, 5-10 E, ... and grid point (72,20) contains the index for 45-50 S, 175-180 W.

  In the data set, each month starts with an ASCII header to identify the year and month. The data is in 10F8.1 format. Each value is the average of AM and PM estimates and corrected for beam filling error. The equation used is: (AM PM)/2.0 * 1.8. Land pixels are set to -10.0. Also there are 33 pixels blocked out due to island contamination (-10.0). If the rain retrieval did not converge, a -10.0 is assigned to the pixel.

 The objective of this data set was to provide a long term monthly rainfall data set to be used in EOS global change and GEWEX related research.

    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.

    Downloads & Resources

    Dates

    Metadata Created Date November 12, 2020
    Metadata Updated Date April 11, 2025

    Metadata Source

    Harvested from NASA Data.json

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Created Date November 12, 2020
    Metadata Updated Date April 11, 2025
    Publisher NASA/GSFC/SED/ESD/GCDC/GESDISC
    Maintainer
    Identifier C1280859286-GES_DISC
    Data First Published 1987-07-01
    Language en-US
    Data Last Modified 2025-03-31
    Category GPCP, geospatial
    Public Access Level public
    Bureau Code 026:00
    Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
    Schema Version https://project-open-data.cio.gov/v1.1/schema
    Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
    Harvest Object Id 20592aff-b685-440e-bea9-ca776ce5ac89
    Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
    Harvest Source Title NASA Data.json
    Homepage URL https://cmr.earthdata.nasa.gov:443/search/concepts/C1280859286-GES_DISC.html
    Metadata Type geospatial
    Old Spatial -180.0 -50.0 180.0 50.0
    Program Code 026:001
    Source Datajson Identifier True
    Source Hash 5e61bd054e7deb28aa435faad8b3a8e39f9f4c8dda8115bc2f98e326887daceb
    Source Schema Version 1.1
    Spatial
    Temporal 1987-07-01T00:00:00Z/1995-12-31T23:59:59.999Z

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