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Dataset Title:	Chlorophyll-a Data Derived From Satellite Images for the Estuary and Gulf of St. Lawrence, Since 1997 \| Données de chlorophylle-a dérivées d'images satellitaires pour l'estuaire et le golfe du St-Laurent, depuis 1997
Institution:	Fisheries and Oceans Canada (Dataset ID: mpoChloroSatellitesCciSince1997v2)
Information:	Summary \| License \| FGDC \| ISO 19115 \| Metadata \| Background \| Data Access Form \| Files

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Y Axis:
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time (UTC)

specify just 1 value →

latitude (degrees_north)

longitude (degrees_east)

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Things You Can Do With Your Graphs

Well, you can do anything you want with your graphs, of course. But some things you might not have considered are:

Web page authors can embed a graph of the latest data in a web page using HTML <img> tags.
Anyone can use ERDDAPs Slide Sorter to build a personal web page that displays graphs with the latest data (or other images or HTML content), each in its own, draggable slide.

The Dataset Attribute Structure (.das) for this Dataset

Attributes {
  time {
    String _CoordinateAxisType "Time";
    Float64 actual_range 8.733312e+8, 1.6409088e+9;
    String axis "T";
    String ioos_category "Time";
    String long_name "Date";
    String standard_name "time";
    String time_origin "01-JAN-1970 00:00:00";
    String time_precision "1/1/1970";
    String units "seconds since 1970-01-01T00:00:00Z";
  }
  latitude {
    String _CoordinateAxisType "Lat";
    Float32 actual_range 45.1875, 51.89583;
    String axis "Y";
    String ioos_category "Location";
    String long_name "Latitude";
    String standard_name "latitude";
    String units "degrees_north";
  }
  longitude {
    String _CoordinateAxisType "Lon";
    Float32 actual_range -71.3125, -55.39583;
    String axis "X";
    String ioos_category "Location";
    String long_name "Longitude";
    String standard_name "longitude";
    String units "degrees_east";
  }
  chl_a_Multisat {
    Float64 colorBarMaximum 30.0;
    Float64 colorBarMinimum 0.01;
    String colorBarScale "Log";
    String description "Chlorophyll a concentration determined by analysis and synthesis of calibrated data from multiple sensors on one or more satellite platforms.";
    String ioos_category "Ocean Color";
    String long_name "Chlorophyll a Concentration";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/CHLAMSAT/";
    String nerc_standard_name "chl_a_Multisat";
    String original_name "chl_eof";
    String standard_name "concentration_of_chlorophyll_in_sea_water";
    String units "mg m-3";
  }
  Rrs_412nm_model {
    String description "Remote sensing reflectance of electromagnetic radiation (412nm wavelength) {Rrs} from the water body by model prediction";
    String long_name "Electromagnetic Radiation (412nm wavelength)";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/RRSWMP02/";
    String nerc_standard_name "Rrs_412nm_model";
    String original_name "Rrs_412";
    String units "sr-1";
  }
  Rrs_443nm_model {
    String description "Remote sensing reflectance of electromagnetic radiation (443nm wavelength) {Rrs} from the water body by model prediction";
    String long_name "Electromagnetic Radiation (443nm wavelength)";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/RRSWMP03/";
    String nerc_standard_name "Rrs_443nm_model";
    String original_name "Rrs_443";
    String units "sr-1";
  }
  Rrs_490nm_model {
    String description "Remote sensing reflectance of electromagnetic radiation (490nm wavelength) {Rrs} from the water body by model prediction";
    String long_name "Electromagnetic Radiation (490nm wavelength)";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/RRSWMP07/";
    String nerc_standard_name "Rrs_490nm_model";
    String original_name "Rrs_490";
    String units "sr-1";
  }
  Rrs_510nm_model {
    String description "Remote sensing reflectance of electromagnetic radiation (510nm wavelength) {Rrs} from the water body by model prediction";
    String long_name "Electromagnetic Radiation (510nm wavelength)";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/RRSWMP08/";
    String nerc_standard_name "Rrs_510nm_model";
    String original_name "Rrs_510";
    String units "sr-1";
  }
  Rrs_560nm_model {
    String description "Remote sensing reflectance of electromagnetic radiation (560nm wavelength) {Rrs} from the water body by model prediction";
    String long_name "Electromagnetic Radiation (560nm wavelength)";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/RRSWMP13/";
    String nerc_standard_name "Rrs_560nm_model";
    String original_name "Rrs_560";
    String units "sr-1";
  }
  Rrs_665nm_model {
    String description "Electromagnetic Radiation (665nm wavelength)";
    String long_name "Electromagnetic Radiation (665nm wavelength)";
    String nerc_identifier "https://vocab.nerc.ac.uk/collection/P01/current/RRSWMP18/";
    String nerc_standard_name "Rrs_665nm_model";
    String original_name "Rrs_665";
    String units "sr-1";
  }
  NC_GLOBAL {
    String cdm_data_type "Grid";
    String Conventions "CF-1.8 COARDS ACDD-1.3";
    String creator_email "Julien.Laliberte@dfo-mpo.gc.ca";
    String creator_identifier "https://orcid.org/0000-0001-6698-029X";
    String creator_name "Julien Laliberté";
    String data_curator "St. Lawrence Global Observatory";
    String data_curator_fr "Observatoire Global du Saint-Laurent";
    String dataset_ogsl_ckan_url "https://catalogue.ogsl.ca/dataset/ca-cioos_969715ba-3747-42ec-b8b4-6280403562d4";
    String dataset_status "OnGoing";
    String date_created "2022-10-07";
    String DOI "https://doi.org/10.26071/ogsl-969715ba-3747";
    Float64 Easternmost_Easting -55.39583;
    String format_version "v2";
    Float64 geospatial_lat_max 51.89583;
    Float64 geospatial_lat_min 45.1875;
    Float64 geospatial_lat_resolution 0.041666645962732896;
    String geospatial_lat_units "degrees_north";
    Float64 geospatial_lon_max -55.39583;
    Float64 geospatial_lon_min -71.3125;
    Float64 geospatial_lon_resolution 0.04166667539267017;
    String geospatial_lon_units "degrees_east";
    String history 
"First version was text file publish directly in the SLGO catalogue. This second version is completely standardized and in NetCDF format. The model algorithm has also change between the two versions.
2024-11-05T14:06:58Z (local files)
2024-11-05T14:06:58Z https://erddap.ogsl.ca/griddap/mpoChloroSatellitesCciSince1997v2.das";
    String infoUrl "https://ogsl.ca/";
    String institution "Fisheries and Oceans Canada";
    String institution_fr "Pêches et Océans Canada";
    String institution_identifier "https://ror.org/02qa1x782";
    String key_variables "oceanColor";
    String keywords "chlorophyll a, model data, phytoplankton, remote sensing, satellites";
    String keywords_fr "chlorophylle a, phytoplancton, télédétection, satellites, données de modèle";
    String keywords_vocabulary "NASA Global Change Master Directory (GCMD) Science Keywords and homemade keywords";
    String license "Open Government Licence - Canada";
    Float64 Northernmost_Northing 51.89583;
    String origin "ESA CCI satellite data";
    String platform "Sentinel-3A, Sentinel-3B, Aqua, Envisat, ORBVIEW 2 (SEASTAR), NOAA 20";
    String platform_id "2016-011A, 2018-039A, 2002-022A, 2002-009A, 1997-037A, 2017-073A";
    String product_version "v2";
    String project "Coastal Environmental Baseline Program";
    String publisher "St. Lawrence Global Observatory";
    String publisher_fr "Observatoire Global du Saint-Laurent";
    String publisher_identifier "https://ror.org/03wfagk22";
    String relatedDataset_ogsl_ckan_url "https://catalogue.ogsl.ca/fr/dataset/dcb7ed2e-bce9-40c5-a197-71ac6b46bd5c";
    String sensor "VIIRS, SeaWiFS, MERIS, OLCI";
    String sourceUrl "(local files)";
    Float64 Southernmost_Northing 45.1875;
    String standard_name_nerc_vocabulary "The NERC Vocabulary Server (NVS).";
    String standard_name_vocabulary "CF Standard Name Table v79";
    String summary "This dataset presents the result of a model developed to retrieve chlorophyll-a (chla) concentration from various satellites in the St. Lawrence Estuary and Gulf. This second version is an extension of the first one(https://catalogue.ogsl.ca/dataset/dcb7ed2e-bce9-40c5-a197-71ac6b46bd5c), with estimates derived from a retuning of the model based on additional in situ and satellite-derived data. The input data is now exclusively from the European Space Agency's Ocean Color Climate Change Initiative (CCI) program. This dataset is produced as part of the Coastal Environmental Baseline Data Program under Fisheries and Oceans Canada's Oceans Protection Plan.";
    String summary_fr "Ce jeu de données présente le résultat d'une méthode développée pour retrouver la concentration de chlorophylle-a (chla) dérivée par divers satellites dans l'estuaire et le golfe du St-Laurent. Cette version des données de concentrations en chla est une mise-à-jour de la première version (https://catalogue.ogsl.ca/dataset/dcb7ed2e-bce9-40c5-a197-71ac6b46bd5c) et est basée sur de nouvelles données in situ et satellitaires. Les données de base proviennent exclusivement du programme Ocean Color Climate Change Initiative (CCI) de l'Agence Spatiale Européenne. Ce projet fait partie du Programme sur les données environnementales côtières de référence dans le cadre du Plan de protection des océans de Pêches et Océans Canada.";
    String time_coverage_end "2021-12-31T00:00:00Z";
    String time_coverage_start "1997-09-04T00:00:00Z";
    String title "Chlorophyll-a Data Derived From Satellite Images for the Estuary and Gulf of St. Lawrence, Since 1997 | Données de chlorophylle-a dérivées d'images satellitaires pour l'estuaire et le golfe du St-Laurent, depuis 1997";
    String update_frequency "Annually";
    Float64 Westernmost_Easting -71.3125;
  }
}

Using griddap to Request Data and Graphs from Gridded Datasets

griddap lets you request a data subset, graph, or map from a gridded dataset (for example, sea surface temperature data from a satellite), via a specially formed URL. griddap uses the OPeNDAP (external link)

Data Access Protocol (DAP) (external link)

and its projection constraints (external link)

The URL specifies what you want: the dataset, a description of the graph or the subset of the data, and the file type for the response.

(easy) You can get data by using the dataset's Data Access Form. It makes the URL for you.
(easy) You can make a graph or map by using the dataset's Make A Graph form. It makes the URL for you.
(not hard) You can bypass the forms and get the data or make a graph or map by generating the URL by hand or with a computer program or script.

griddap request URLs must be in the form
https://coastwatch.pfeg.noaa.gov/erddap/griddap/datasetID.fileType{?query}
For example,
https://coastwatch.pfeg.noaa.gov/erddap/griddap/jplMURSST41.htmlTable?analysed_sst[(2002-06-01T09:00:00Z)][(-89.99):1000:(89.99)][(-179.99):1000:(180.0)]
Thus, the query is often a data variable name (e.g., analysed_sst), followed by [(start):stride:(stop)] (or a shorter variation of that) for each of the variable's dimensions (for example, [time][latitude][longitude]).

For details, see the griddap Documentation.