Chlorophyll-a Average Annual Maximum Anomaly, 2002-2013 - Hawaii

Metadata Updated: November 12, 2020

Chlorophyll-a is a widely used proxy for phytoplankton biomass and an indicator for changes in phytoplankton production. As an essential source of energy in the marine environment, the extent and availability of phytoplankton biomass can be highly influential for fisheries production and dictate trophic structure in marine ecosystems. Changes in phytoplankton biomass are predominantly effected by changes in nutrient availability, through either natural (e.g., turbulent ocean mixing) or anthropogenic (e.g., agricultural runoff) processes. This layer represents the annual average of the maximum anomaly of chlorophyll-a (mg/m3) from 2002-2013. Monthly and 8-day 4-km (0.0417-degree) spatial resolution data were obtained from the MODIS (Moderate-resolution Imaging Spectroradiometer) Aqua satellite instrument from the NASA OceanColor website (http://oceancolor.gsfc.nasa.gov).

The chlorophyll-a average annual maximum anomaly was calculated by taking the average of the chlorophyll-a values from the 8-day time series in exceedance of the maximum monthly climatological chlorophyll-a from 2002-2013 for each pixel. A quality control mask was applied to remove spurious data associated with shallow water, following Gove et al., 2013. Monthly Climatologies were calculated from monthly time series using only full years over the Ocean Tipping Points (OTP) project time frame of interest (2002-2013). 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.

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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 March 14, 2017
Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020
Reference Date(s) March 14, 2017 (creation), March 14, 2017 (issued), March 14, 2017 (revision)
Frequency Of Update

Metadata Source

Harvested from ioos

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Additional Metadata

Resource Type Dataset
Metadata Date March 14, 2017
Metadata Created Date November 12, 2020
Metadata Updated Date November 12, 2020
Reference Date(s) March 14, 2017 (creation), March 14, 2017 (issued), March 14, 2017 (revision)
Responsible Party Ocean Tipping Points (OTP) (Point of Contact)
Contact Email
Guid hi_otp_all_chlor_anom_max
Access Constraints
Bbox East Long -154.56326617912035
Bbox North Lat 22.42373568629166
Bbox South Lat 18.755036208219373
Bbox West Long -160.41246354980814
Coupled Resource [{"href": ["#DataIdentification"], "uuid": [], "title": []}, {"href": ["#DataIdentification"], "uuid": [], "title": []}, {"href": ["#DataIdentification"], "uuid": [], "title": []}]
Frequency Of Update
Graphic Preview Description Sample image.
Graphic Preview File http://pacioos.org/metadata/browse/hi_otp_all_chlor_anom_max.png
Licence
Metadata Language eng
Metadata Type geospatial
Progress
Spatial Data Service Type Open Geospatial Consortium Web Coverage Service (WCS)
Spatial Reference System
Spatial Harvester True

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