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    • NOAA Climate Data Record (CDR) of AVHRR Surface Reflectance, Version 4 (Version Superseded)

    Metadata Updated: December 12, 2025

    Note: This dataset version has been superseded by a newer version. It is highly recommended that users access the current version. Users should only use this version for special cases, such as reproducing studies that used this version. This dataset contains gridded daily surface reflectance and brightness temperatures derived from the Advanced Very High Resolution Radiometer (AVHRR) sensors onboard eight NOAA polar orbiting satellites: NOAA-7, -9, -11, -14, -16, -17, -18 and -19. Surface reflectance from AVHRR channels 1 and 2 (at 640 and 860 nm) are a NOAA Climate Data Record (CDR). The dataset spans from 1981 to 10 days before the present, and was processed from the AVHRR Global Area Coverage (GAC) Level 1b dataset. AVHRR GAC observations are packaged into data arrays with latitude and longitude dimensions of 3600 x 7200 covering the globe at 0.05 degree spatial resolution. This dataset is one of the Land Surface CDR products produced by the NASA Goddard Space Flight Center (GSFC) and the University of Maryland (UMD). Other Land Surface CDR products include the Normalized Difference Vegetation Index (NDVI), Leaf Area Index (LAI) and Fraction of Absorbed Photosynthetically Active Radiation (FAPAR). Improvements made for Version 4 include 1) additional data from NOAA satellites extending the time period, 2) improved geolocation accuracy from use of OLE instead of TLE, 3) center of the grid is used as the reference, and 4) data value of a grid cell is computed as an average of available good observations. The dataset is in the netCDF-4 file format following ACDD and CF Conventions. The dataset is accompanied by algorithm documentation, data flow diagram and source code for the NOAA CDR Program.

    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 September 18, 2023
    Metadata Created Date December 12, 2025
    Metadata Updated Date December 12, 2025
    Reference Date(s) May 21, 2014 (publication)
    Frequency Of Update notPlanned

    Metadata Source

    Harvested from ncdc

    Other Data Resources

    Graphic Preview

    Global image of daily AVHRR surface reflectance

    Additional Metadata

    Resource Type Dataset
    Metadata Date September 18, 2023
    Metadata Created Date December 12, 2025
    Metadata Updated Date December 12, 2025
    Reference Date(s) May 21, 2014 (publication)
    Responsible Party DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce (Point of Contact)
    Contact Email
    Guid gov.noaa.ncdc:C00811
    Access Constraints Cite as: Vermote, Eric; Justice, Chris; Csiszar, Ivan; Eidenshink, Jeff; Myneni, Ranga B.; Baret, Frederic; Masuoka, Ed; Wolfe, Robert E.; Claverie, Martin; NOAA CDR Program. (2014): NOAA Climate Data Record (CDR) of AVHRR Surface Reflectance, Version 4. [indicate subset used]. NOAA National Centers for Environmental Information. https://doi.org/10.7289/V5TM782M. Accessed [date]., See the Use Agreement for this dataset available on the CDR page., 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 notPlanned
    Graphic Preview Description Global image of daily AVHRR surface reflectance
    Graphic Preview File https://www.ncei.noaa.gov/pub/data/metadata/images/C00811_SR_lowRes.png
    Graphic Preview Type PNG
    Harvest Object Id dc51bf98-6843-46b4-b89c-e38920fa3459
    Harvest Source Id 2cb3ef77-1683-4c2a-9119-dc65e50917c6
    Harvest Source Title ncdc
    Licence *Note: This dataset version has been superseded by a newer version. It is highly recommended that users access the current version. Users should only use this version for special cases, such as reproducing studies that used this version.*, Data for some days in the CDR series may be missing for one or more of the following reasons: 1) input GAC data was not available, 2) the data day was found to contain significant geolocation residual error, or 3) noisy input data., The time variable in the data files has values that are too large by one (1) day. See the Technical Note., See the Algorithm Theoretical Basis Document (ATBD) for a description of this dataset's use limitations.
    Lineage This dataset was produced by the NASA Goddard Space Flight Center (GSFC) and the University of Maryland (UMD), and is archived at the NOAA National Centers for Environmental Information (NCEI).
    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 completed
    Spatial Data Service Type
    Spatial Reference System
    Spatial Harvester True
    Temporal Extent Begin 1981-06-24
    Temporal Extent End 2019-07-11

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