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    • NOAA Climate Data Record (CDR) of AVHRR Daily and Monthly Aerosol Optical Thickness (AOT) over Global Oceans, Version 4.0

    Metadata Updated: September 19, 2023

    The product is the aerosol optical thickness (AOT) at 0.63 micron, which is retrieved from NOAA PATMOS-x AVHRR+HIRS level-2B orbital radiance and cloud CDR products. The retrieval is performed for selected spatial (0.1 by 0.1 degree) and temporal (1 time per day per satellite) resolution in cloud free conditions during daytime. The final product is daily averaged from all satellite retrievals and in a 0.1 by 0.1 degree equal angle grid (total 1800x3600 grids over the globe). Due to the relatively large uncertainties associated with surface reflectance over water glint area and land surface as well as limited AVHRR retrieval channels, the current algorithm only performs retrieval over none-glint water surface (specifically at the anti-solar side of the orbit and viewing angle is larger than 40 degree away from the specular ray). The final CDR AOT products include daily and monthly products.

    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 August 10, 2023
    Metadata Created Date February 3, 2023
    Metadata Updated Date September 19, 2023
    Reference Date(s) June 20, 2022 (publication)
    Frequency Of Update quarterly

    Metadata Source

    Harvested from ncdc

    Other Data Resources

    Graphic Preview

    Long-term averaged aerosol optical thickness (AOT) over the global oceans

    Additional Metadata

    Resource Type Dataset
    Metadata Date August 10, 2023
    Metadata Created Date February 3, 2023
    Metadata Updated Date September 19, 2023
    Reference Date(s) June 20, 2022 (publication)
    Responsible Party NOAA National Centers for Environmental Information (Point of Contact); 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:C01678
    Access Constraints Cite as: Zhao, Xuepeng; and NOAA CDR Program: NOAA Climate Data Record (CDR) of AVHRR Daily and Monthly Aerosol Optical Thickness (AOT) over Global Oceans, Version 4.0. [indicate subset used]. NOAA National Centers for Environmental Information. doi:10.25921/w3zj-4y48 [date accessed]., See the Use Agreement for this CDR 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 quarterly
    Graphic Preview Description Long-term averaged aerosol optical thickness (AOT) over the global oceans
    Graphic Preview File https://www.ncei.noaa.gov/pub/data/metadata/images/C01678_AOT_CDR_v4.0.jpg
    Graphic Preview Type JPEG
    Harvest Object Id e8f41527-7d4f-47d7-b6e8-22002ec5a371
    Harvest Source Id 2cb3ef77-1683-4c2a-9119-dc65e50917c6
    Harvest Source Title ncdc
    Licence See the Algorithm Theoretical Basis Document for a description of the use limitations for this dataset. Products apply to over-ocean only. The values at polar latitudes (outside 60 degree north or south) are degraded due to surface contamination from ice and degraded cloud screening at polar latitudes. The quality of the output CDR data is dependent on the quality of the input data. As such, the near real-time data is labeled as an Interim operational CDR (ICDR) or preliminary CDR instead of a final CDR, indicating that it has not yet been fully vetted for climate applications. The near real-time ICDR/preliminary data will transition to final CDR status after the data have undergone further analysis and processing. The expected time lag of the final CDR transition is approximately one year. The state of a data file is indicated within each file name.
    Lineage The data were produced by and are 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 onGoing
    Spatial Data Service Type
    Spatial Reference System
    Spatial Harvester True
    Temporal Extent Begin 1982-01-01

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