Chlorophyll-a Average Annual Frequency of Anomalies, 2002-2013 - Hawaii
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 number of anomalies of chlorophyll-a (mg/m3) from 2002-2013, with values presented as fraction of a year. 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 frequency of anomalies was calculated by taking the average number of times that the 8-day time series exceeded the maximum monthly climatological chlorophyll-a value 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.
Complete Metadata
| @type | dcat:Dataset |
|---|---|
| accessLevel | public |
| contactPoint |
{
"fn": "National Center for Ecological Analysis and Synthesis (NCEAS)",
"@type": "vcard:Contact",
"hasEmail": "mailto:kappel@nceas.ucsb.edu"
}
|
| describedByType | application/octet-steam |
| description | 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 number of anomalies of chlorophyll-a (mg/m3) from 2002-2013, with values presented as fraction of a year. 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 frequency of anomalies was calculated by taking the average number of times that the 8-day time series exceeded the maximum monthly climatological chlorophyll-a value 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. |
| distribution |
[
{
"@type": "dcat:Distribution",
"title": "GeoServer",
"mediaType": "placeholder/value",
"description": "This URL provides access to this dataset via GeoServer, including multiple output formats and an OpenLayers viewer.",
"downloadURL": "https://geo.pacioos.hawaii.edu/geoserver/",
"describedByType": "application/octet-steam"
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{
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"title": "PacIOOS Ocean Tipping Points (OTP) Data Viewer",
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|
| identifier | hi_otp_all_chlor_anom_freq |
| isPartOf | Pacific Islands Ocean Observing System (PacIOOS) |
| issued | 2017-03-14T00:00:00.000+00:00 |
| keyword |
[
"Earth Science > Biosphere > Aquatic Ecosystems > Reef Habitat",
"Earth Science > Biosphere > Ecosystems > Marine Ecosystems > Reef > Coral Reef",
"Earth Science > Human Dimensions > Human Settlements > Coastal Areas",
"Earth Science > Oceans > Coastal Processes > Coral Reefs",
"Earth Science > Oceans > Ocean Chemistry > Chlorophyll",
"Earth Science > Oceans > Ocean Optics > Ocean Color",
"Continent > North America > United States Of America > Hawaii",
"Ocean > Pacific Ocean > Central Pacific Ocean > Hawaiian Islands",
"PacIOOS > Pacific Islands Ocean Observing System",
"PacIOOS > Pacific Islands Ocean Observing System"
]
|
| landingPage | http://oceantippingpoints.org/about-us/people#Carrie |
| language |
[]
|
| license | https://creativecommons.org/publicdomain/zero/1.0/ |
| modified | 2017-03-14T00:00:00.000+00:00 |
| publisher |
{
"name": "Pacific Islands Ocean Observing System (PacIOOS)",
"@type": "org:Organization"
}
|
| spatial | -154.56326617912035,18.755036208219373,-160.41246354980814,22.42373568629166 |
| title | Chlorophyll-a Average Annual Frequency of Anomalies, 2002-2013 - Hawaii |
