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    • Light Attenuation Kd490

    Metadata Updated: October 31, 2024

    This dataset represents monthly and annual mean summaries for Kd490 for the time period from 2000/2001 to 2017/2018, depending on the month and data available (see processing steps). Kd (490) is the diffuse attenuation coefficient at 490 nm. The diffuse attenuation coefficient in water indicates how strongly light intensity at a specified wavelength is attenuated within the water column. This parameter has wide applicability in ocean optics, as it is directly related to the presence of scattering particles in the water column, either organic or inorganic, and thus is an indication of water clarity. The diffuse attenuation coefficient at 490 nm (Kd490) indicates the turbidity of the water column -- how visible light in the blue to green region of the spectrum penetrates within the water column. The value of Kd490 (m-1) represents the rate at which light at 490 nm is attenuated with depth. For example, a Kd490 of 0.1/meter means that light intensity will be reduced one natural log within 10 meters of water. Thus, for a Kd490 of 0.1, one attenuation length is 10 meters. Higher Kd490 value means smaller attenuation depth and lower clarity of ocean water.

    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.

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    Dates

    Metadata Date August 15, 2024
    Metadata Created Date October 31, 2024
    Metadata Updated Date October 31, 2024
    Reference Date(s) (publication)
    Frequency Of Update asNeeded

    Metadata Source

    Harvested from NOS OCM

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Date August 15, 2024
    Metadata Created Date October 31, 2024
    Metadata Updated Date October 31, 2024
    Reference Date(s) (publication)
    Responsible Party NOAA Office for Coastal Management (Point of Contact)
    Contact Email
    Guid gov.noaa.nmfs.inport:66147
    Access Constraints Cite As: Office for Coastal Management, [Date of Access]: Light Attenuation Kd490 [Data Date Range], https://www.fisheries.noaa.gov/inport/item/66147., Use Constraints: For coastal and ocean planning, Distribution Liability: https://www.marinecadastre.gov/about/disclaimer.html
    Bbox East Long 179.999996
    Bbox North Lat 74.710722
    Bbox South Lat -17.584128
    Bbox West Long -179.999989
    Coupled Resource
    Frequency Of Update asNeeded
    Harvest Object Id 8a7bee97-d5dd-465c-807f-900b6f4b4138
    Harvest Source Id c0121fd9-df15-4168-ac04-42f6e36a794d
    Harvest Source Title NOS OCM
    Licence NOAA provides no warranty, nor accepts any liability occurring from any incomplete, incorrect, or misleading data, or from any incorrect, incomplete, or misleading use of the data. It is the responsibility of the user to determine whether or not the data is suitable for the intended purpose.
    Lineage
    Metadata Language eng
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[-179.999989, -17.584128], [179.999996, -17.584128], [179.999996, 74.710722], [-179.999989, 74.710722], [-179.999989, -17.584128]]]}
    Progress completed
    Spatial Data Service Type
    Spatial Reference System
    Spatial Harvester True

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