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

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.

Data and Resources

Additional Info

Field Value
Maintainer ALFRED CHANG
Last Updated March 31, 2025, 23:29 (UTC)
Created March 31, 2025, 23:29 (UTC)
accessLevel public
bureauCode {026:00}
catalog_@context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
catalog_@id https://data.nasa.gov/data.json
catalog_conformsTo https://project-open-data.cio.gov/v1.1/schema
catalog_describedBy https://project-open-data.cio.gov/v1.1/schema/catalog.json
citation Chang, A. 2011-04-25. RAIN_CHANG. Version 2.3. Chang SSM/I Derived Monthly Rain Indices 5 x 5 degree V2.3. Greenbelt, MD, USA. Archived by National Aeronautics and Space Administration, U.S. Government, Goddard Earth Sciences Data and Information Services Center (GES DISC). https://disc.gsfc.nasa.gov/datacollection/RAIN_CHANG_2.3.html. Digital Science Data.
creator Chang, A
data-presentation-form Digital Science Data
graphic-preview-file https://docserver.gesdisc.eosdis.nasa.gov/public/project/Images/RAIN_CHANG_2.3.png
harvest_object_id f1919e5c-b187-4817-8761-55a450921457
harvest_source_id 61638e72-b36c-4866-9d28-551a3062f158
harvest_source_title DNG Legacy Data
identifier C1280859286-GES_DISC
issued 1987-07-01
landingPage https://cmr.earthdata.nasa.gov:443/search/concepts/C1280859286-GES_DISC.html
language {en-US}
metadata_type geospatial
modified 1995-12-31
programCode {026:001}
publisher NASA/GSFC/SED/ESD/GCDC/GESDISC
release-place Greenbelt, MD, USA
resource-type Dataset
series-name RAIN_CHANG
source_datajson_identifier true
source_hash 36ddd78943b77879275962c165cc0b84200d5da4111fca0b76c7ba31c81e60e8
source_schema_version 1.1
spatial -180.0 -50.0 180.0 50.0
temporal 1987-07-01T00:00:00Z/1995-12-31T23:59:59.999Z
theme {GPCP,geospatial}