SSMI(S) Hydrological Products

browse graphicSSMI-SSMIS Hydrological Products image example
The Special Sensor Microwave/Imager (SSM/I) and Special Sensor Microwave Imager-Sounder (SSMIS) have been making measurements of earth-emitted microwave radiation for over two decades. Antenna temperature data from these sensors are used to derive both atmospheric and surface hydrological parameters and to generate these global monthly mean products. Specifically, this includes monthly or 5-day estimates of rainfall and its frequency, cloud liquid water and cloud frequency, water vapor, liquid water path, snow cover frequency, satellite sampling frequency and various imagery. The data collection consists of five different products: the Monthly 2.5 Degree Gridded Dataset, the Monthly 1.0 Degree Gridded Dataset, the Pentad 2.5 Degree Gridded Dataset, Imagery, and specially formatted files used in the Global Precipitation Climatology Project Dataset (GPCP). All data in this collection (except the Pentad and Imagery datasets) extend from July 1987 until present.

Monthly 2.5 Degree Gridded Dataset
Products included in this domain are taken from early orbits and include: mean cloud fraction (cfr), mean sea-ice cover (ice), liquid water path (lwp), mean rain fraction (pf2), rainfall (pr1), snow cover fraction (snw), mean sampling fraction (ssa), and mean total precipitable water (wvp). Products are averaged to 2.5 degree lat × 2.5 degree long grids.

Imagery
This dataset portrays monthly estimates of precipitable water (wvp), liquid water path (lwp), rainfall (pr1), and snow cover in both color and black and white. This domain of the SSM/I and SSMIS archive includes images of data from January 2006 to the present.

GPCP Input files
This time series domain of the SSM/I and SSMIS archive is formatted for the production of GPCP (Global Precipitation Climatology Project) datasets. The dataset is processed using early and late orbits plus a special "dual" orbit that combines the early and late satellite data. Products include rainfall (pr1 and pr2) and mean sampling fraction (ssa). The product is averaged to 2.5 degrees lat × 2.5 degrees long grids.

Binary
All data is also available in a legacy binary format, with the addition of a daily and pentad product. Products included in the daily domain are taken from early orbits and include: mean cloud fraction (cfr), mean sea-ice cover (ice), liquid water path (lwp), mean rain fraction (pf2), rainfall (pr1), snow cover fraction (snw), mean sampling fraction (ssa), and mean total precipitable water (wvp). Products are averaged to 1 lat x 1 long grids. Products included in Pentad domain are taken from specific satellite orbits and include: mean cloud fraction (cfr), mean sea-ice cover (ice), liquid water path (lwp), mean rain fraction (pf1 and pf2), rainfall (pr1 and pr2), snow cover fraction (snw), mean sampling fraction (ssa), and mean total precipitable water (wvp). Products are averaged to 2.5 lat x 2.5 long grids using 5-day estimates of rainfall and its frequency, cloud liquid water and cloud frequency, water vapor, liquid water path, snow cover frequency, satellite sampling frequency and various imagery. Pentad data only includes data from March 2008 to present.

For a complete description of these products, please refer to all associated documentation.
  • Cite this dataset when used as a source: Semunegus, Hilawe; Ferraro, Ralph: (2012) SSMI(S) Hydrological Products [indicate subset used]. NOAA National Climatic Data Center. doi:10.7289/V5QF8R3K[indicate access date]
  • Please refer to Credit tab for full citation information.
Download Data
Distribution Formats
  • netCDF (Version: 4)
    • File Specification: The NetCDF data files comply with the Climate and Forecast (CF) Metadata Conventions and the NetCDF Attribute Convention for Dataset Discovery (ACDD).
  • Binary
Distributor Customer Engagement Branch
DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
1-828-271-4800
ncei.orders@noaa.gov
Dataset Point of Contact Customer Engagement Branch
DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
1-828-271-4800
ncei.orders@noaa.gov
Time Period 1987-07-01 to Present (time interval: 1-month)
Spatial Bounding Box Coordinates
N: 90.0
S: -90.0
E: 180.0
W: -180.0
Spatial Coverage Map
General Documentation
Associated Resources
Publication Dates
  • publication: 2012-09-01
  • revision: 2017-11-01
Edition Version 1
Data Presentation Form Digital image
Dataset Progress Status Ongoing - data is continually being updated
Data Update Frequency Monthly
Purpose This product is used to detect anomalies in precipitation patterns on a global scale. These products are useful for evaluating mean global precipitation, its interannual and seasonal variations, and the detection of anomalies associated with large-scale (e.g. ENSO, Arctic Oscillation) and regional climatic variations. Current users include members of the GPCP and the Climate Prediction Center, as well as various academic/government researchers nationally and internationally. It is a key input data source for the Global Precipitation Climatology Project (GPCP).
Use Limitations
  • In October 2017, 2.5 degree and gpcp-input data files were identified as having the incorrect data date encoded in the netCDF. These files have been replaced in the archive. Users are encouraged to use data files with a create date later than October 18, 2017 to ensure they are using the best quality file.
Dataset Citation
  • Cite this dataset when used as a source: Semunegus, Hilawe; Ferraro, Ralph: (2012) SSMI(S) Hydrological Products [indicate subset used]. NOAA National Climatic Data Center. doi:10.7289/V5QF8R3K[indicate access date]
  • Please also cite the following science paper when using this dataset: Vila, D., C. Hernandez, R. Ferraro, and H. Semunegus, 2013: The Performance of Hydrological Monthly Products Using SSM/I-SSMI/S Sensors. J. Hydrometeor., 14, 266-274, https://doi.org/10.1175/JHM-D-12-056.1
  • Please also cite the following science paper when using this dataset: Ferraro, R.R., N.C. Grody, F. Weng, and A. Basist, 1996: An Eight-Year (1987-1994) Time Series of Rainfall, Clouds, Water Vapor, Snow Cover, and Sea Ice Derived from SSM/I Measurements. Bull. Amer. Meteor. Soc., 77, 891-905, https://doi.org/10.1175/1520-0477(1996)077<0891:AEYTSO>2.0.CO;2
Cited Authors
  • Hilawe Semunegus
    DOC/NOAA/NESDIS/NCDC > National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce
  • Ralph Ferraro
    DOC/NOAA/NESDIS/STAR > Center for Satellite Applications and Research, NESDIS, NOAA, U.S. Department of Commerce
Principal Investigators
  • Hilawe Semunegus
    DOC/NOAA/NESDIS/NCDC > National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce
  • Ralph Ferraro
    DOC/NOAA/NESDIS/STAR > Center for Satellite Applications and Research, NESDIS, NOAA, U.S. Department of Commerce
Publishers
  • DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
Theme keywords Global Change Master Directory (GCMD) Science Keywords
  • Earth Science > Cryosphere > Snow/Ice > Snow Cover
  • Earth Science > Cryosphere > Sea Ice > Ice Extent
  • Earth Science > Atmosphere > Clouds > Cloud Properties > Cloud Frequency
  • Earth Science > Atmosphere > Atmospheric Water Vapor
  • Earth Science > Atmosphere > Precipitation > Precipitation Rate
  • Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Indicators > Total Precipitable Water
Global Climate Observing System (GCOS) Essential Climate Variables (ECVs)
  • Atmospheric - Surface - Precipitation
Data Center keywords Global Change Master Directory (GCMD) Data Center Keywords
  • DOC/NOAA/NESDIS/NCDC > National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce
  • DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce
Platform keywords Global Change Master Directory (GCMD) Platform Keywords
  • DMSP 5D-2/F8 > Defense Meteorological Satellite Program-F8
  • DMSP 5D-2/F10 > Defense Meteorological Satellite Program-F10
  • DMSP 5D-2/F11 > Defense Meteorological Satellite Program-F11
  • DMSP 5D-2/F13 > Defense Meteorological Satellite Program-F13
  • DMSP 5D-2/F14 > Defense Meteorological Satellite Program-F14
  • DMSP 5D-3/F15 > Defense Meteorological Satellite Program-F15
  • DMSP 5D-3/F16 > Defense Meteorological Satellite Program-F16
  • DMSP 5D-3/F17 > Defense Meteorological Satellite Program-F17
  • DMSP 5D-3/F18 > Defense Meteorological Satellite Program-F18
Instrument keywords Global Change Master Directory (GCMD) Instrument Keywords
  • SSMIS > Special Sensor Microwave Imager/Sounder
  • SSMI > Special Sensor Microwave/Imager
Place keywords Global Change Master Directory (GCMD) Location Keywords
  • Geographic Region > Global
Data Resolution keywords Global Change Master Directory (GCMD) Temporal Data Resolution Keywords
  • Monthly Climatology
Global Change Master Directory (GCMD) Horizontal Data Resolution Keywords
  • 100 km - < 250 km or approximately 1 degree - < 2.5 degrees
Stratum keywords Global Change Master Directory (GCMD) Location Keywords
  • Vertical Location > Land Surface
  • Vertical Location > Troposphere
Use Constraints
  • Cite this dataset when used as a source: Semunegus, Hilawe; Ferraro, Ralph: (2012) SSMI(S) Hydrological Products [indicate subset used]. NOAA National Climatic Data Center. doi:10.7289/V5QF8R3K[indicate access date]
  • Please also cite the following science paper when using this dataset: Vila, D., C. Hernandez, R. Ferraro, and H. Semunegus, 2013: The Performance of Hydrological Monthly Products Using SSM/I-SSMI/S Sensors. J. Hydrometeor., 14, 266-274, https://doi.org/10.1175/JHM-D-12-056.1
  • Please also cite the following science paper when using this dataset: Ferraro, R.R., N.C. Grody, F. Weng, and A. Basist, 1996: An Eight-Year (1987-1994) Time Series of Rainfall, Clouds, Water Vapor, Snow Cover, and Sea Ice Derived from SSM/I Measurements. Bull. Amer. Meteor. Soc., 77, 891-905, https://doi.org/10.1175/1520-0477(1996)077<0891:AEYTSO>2.0.CO;2
  • Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose.
Access Constraints
  • Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives.
Fees
  • In most cases, electronic downloads of the data are free, however fees may apply for data certifications, copies of analog materials, and data distribution on physical media.
Lineage information for: dataset
Lineage Statement For more information about the production of this dataset, users should review the published science papers associated with the dataset.
Processing Steps
  • NetCDF files are produced from the binary files.
  • In October 2017, 2.5 degree and gpcp-input data files were identified as having the incorrect data date encoded in the netCDF. These files have been replaced in the archive. Users are encouraged to use data files with a create date later than October 18, 2017, to ensure they are using the best quality file.
Source Datasets
  • CLASS Search Page for DMSP data
    • CLASS Search Page for DMSP data
      Search for SSMI/SSMIS data from the DMSP CLASS data family.
    • Description of Source: Defense Meteorological Satellite Program
    • Temporal extent used: 1987-07-01 to Present
    • Spatial extent used: N:90.0 S:-90.0 E:180.0 W:-180.0
Lineage information for: repository
Processing Steps
  • 2015-04-22T00:00:00 - NOAA created the National Centers for Environmental Information (NCEI) by merging NOAA's National Climatic Data Center (NCDC), National Geophysical Data Center (NGDC), and National Oceanographic Data Center (NODC), including the National Coastal Data Development Center (NCDDC), per the Consolidated and Further Continuing Appropriations Act, 2015, Public Law 113-235. NCEI launched publicly on April 22, 2015.
Last Modified: 2018-05-25
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