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    • SSMI(S) Hydrological Products

    Metadata Updated: September 19, 2023

    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.

    Access & Use Information

    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 Date June 23, 2023
    Metadata Created Date October 28, 2022
    Metadata Updated Date September 19, 2023
    Reference Date(s) September 1, 2012 (publication), November 1, 2017 (revision)
    Frequency Of Update monthly

    Metadata Source

    Harvested from ncdc

    Other Data Resources

    Graphic Preview

    SSMI-SSMIS Hydrological Products image example

    Additional Metadata

    Resource Type Dataset
    Metadata Date June 23, 2023
    Metadata Created Date October 28, 2022
    Metadata Updated Date September 19, 2023
    Reference Date(s) September 1, 2012 (publication), November 1, 2017 (revision)
    Responsible Party NOAA National Centers for Environmental Information (Point of Contact)
    Contact Email
    Guid gov.noaa.ncdc:C00789
    Access Constraints Cite as: 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, 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., 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.
    Bbox East Long 180.0
    Bbox North Lat 90.0
    Bbox South Lat -90.0
    Bbox West Long -180.0
    Coupled Resource
    Frequency Of Update monthly
    Graphic Preview Description SSMI-SSMIS Hydrological Products image example
    Graphic Preview File https://www.ncei.noaa.gov/pub/data/metadata/images/C00789_mw-hydro-2-5-grid.gif
    Graphic Preview Type GIF
    Harvest Object Id 757d7cff-266d-4e35-9cc7-eedfab3ce589
    Harvest Source Id 2cb3ef77-1683-4c2a-9119-dc65e50917c6
    Harvest Source Title ncdc
    Licence 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.
    Lineage For more information about the production of this dataset, users should review the published science papers associated with the dataset.
    Metadata Language eng; USA
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[-180.0, -90.0], [180.0, -90.0], [180.0, 90.0], [-180.0, 90.0], [-180.0, -90.0]]]}
    Progress onGoing
    Spatial Data Service Type
    Spatial Reference System
    Spatial Harvester True
    Temporal Extent Begin 1987-07-01

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