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    • Photosynthetically Active Radiation (PAR) Average Annual Frequency of Anomalies, 2003-2018 - American Samoa

    Metadata Updated: October 7, 2023

    Solar irradiance is one of the most important factors influencing coral reefs. As a majority of their nutrients are obtained from symbiotic photosynthesizing organisms, reef-building corals need sunlight as a fundamental source of energy. Seasonally low irradiance at high latitudes may be linked to reduced growth rates in corals and may limit reef calcification to shallower depths than that observed at lower latitudes. However, high levels of irradiance can lead to light-induced damage, production of free radicals, and in combination with increased temperatures, can exacerbate coral bleaching. Irradiance is here represented by PAR (photosynthetically active radiation), which is the spectrum of light that is important for photosynthesis. This layer represents the annual average number of anomalies of PAR (mol/m2/day) from 2003-2018, with values presented as fraction of a year.

    Data for PAR for the time period 2003-2018 were obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua satellite instrument from the NASA OceanColor website as 8-day 4-km composites.

    The PAR average annual frequency of anomalies was calculated by taking the average number of weeks that exceeded the maximum monthly climatological PAR value from 2003-2018 for each pixel. A quality control mask was applied to remove spurious data associated with shallow water, following Gove et al., 2013. Time series of anomalies were calculated by quantifying the number and magnitude of events from the 8-day time series that exceed the maximum climatological monthly mean. Nearshore map pixels with no data were filled with values from the nearest neighboring valid offshore pixel by using a grid of points and the Near Analysis tool in ArcGIS then converting points to raster.

    Data source: https://oceanwatch.pifsc.noaa.gov/erddap/griddap/aqua_par_8d_2018_0.graph

    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 September 7, 2021
    Metadata Created Date October 7, 2023
    Metadata Updated Date October 7, 2023
    Reference Date(s) September 7, 2021 (creation), September 7, 2021 (issued), September 7, 2021 (revision)
    Frequency Of Update

    Metadata Source

    Harvested from ioos

    Other Data Resources

    Graphic Preview

    Sample image.

    Additional Metadata

    Resource Type Dataset
    Metadata Date September 7, 2021
    Metadata Created Date October 7, 2023
    Metadata Updated Date October 7, 2023
    Reference Date(s) September 7, 2021 (creation), September 7, 2021 (issued), September 7, 2021 (revision)
    Responsible Party NOAA Pacific Islands Fisheries Science Center (PIFSC) (Point of Contact)
    Contact Email
    Guid as_noaa_all_par_anom_freq
    Access Constraints
    Bbox East Long -167.82502343885935
    Bbox North Lat -10.7765
    Bbox South Lat -14.732043054565562
    Bbox West Long -171.33852999999996
    Coupled Resource [{"title": [], "href": ["#DataIdentification"], "uuid": []}, {"title": [], "href": ["#DataIdentification"], "uuid": []}, {"title": [], "href": ["#DataIdentification"], "uuid": []}]
    Frequency Of Update
    Graphic Preview Description Sample image.
    Graphic Preview File http://pacioos.org/metadata/browse/as_noaa_all_par_anom_freq.png
    Harvest Object Id 9af8b566-3a7d-40ed-adac-8ab8afe26cf9
    Harvest Source Id 54e15a6e-6dde-4c9c-a8f0-345cc0dfccfb
    Harvest Source Title ioos
    Licence
    Lineage 2021-09-07T00:00:00Z OGC web services (WMS and WFS) enabled by PacIOOS via GeoServer. Original data from source provider may have been reformatted, reprojected, or adjusted in other ways to optimize these capabilities.
    Metadata Language eng
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[-171.33852999999996, -14.732043054565562], [-167.82502343885935, -14.732043054565562], [-167.82502343885935, -10.7765], [-171.33852999999996, -10.7765], [-171.33852999999996, -14.732043054565562]]]}
    Progress
    Spatial Data Service Type Open Geospatial Consortium Web Coverage Service (WCS)
    Spatial Reference System
    Spatial Harvester True

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