Make A Graph

Dataset Title:	NOAA Coral Reef Watch Daily Global 5-km Satellite Monitoring Marine Heatwave Watch
Institution:	NOAA Coral Reef Watch (CRW) (Dataset ID: mhw_5km)
Information:	Summary \| License \| FGDC \| ISO 19115 \| Metadata \| Background \| Data Access Form

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Graph Type:
X Axis:
Y Axis:
Color:

Dimensions

Start

Stop

time (UTC)

specify just 1 value →

latitude (degrees_north)

longitude (degrees_east)

Graph Settings
Color Bar:	Continuity:	Scale:
Minimum:	Maximum:	N Sections:
Draw land mask:
Y Axis Minimum:	Maximum:

(Please be patient. It may take a while to get the data.)

Optional:
Then set the File Type: (File Type information)
and

or view the URL:
(Documentation / Bypass this form

)

Click on the map to specify a new center point.

Zoom:

[The graph you specified. Please be patient.]

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 {
    UInt32 _ChunkSizes 1024;
    String _CoordinateAxisType "Time";
    Float64 actual_range 1.7198352e+9, 1.7302032e+9;
    String axis "T";
    String coverage_content_type "coordinate";
    String ioos_category "Time";
    String long_name "reference time of the data";
    String standard_name "time";
    String time_origin "01-JAN-1970 00:00:00";
    String units "seconds since 1970-01-01T00:00:00Z";
  }
  latitude {
    UInt32 _ChunkSizes 3600;
    String _CoordinateAxisType "Lat";
    Float32 actual_range -89.975, 89.975;
    String axis "Y";
    String ioos_category "Location";
    String long_name "Latitude";
    String standard_name "latitude";
    String units "degrees_north";
  }
  longitude {
    UInt32 _ChunkSizes 7200;
    String _CoordinateAxisType "Lon";
    Float32 actual_range -179.975, 179.975;
    String axis "X";
    String ioos_category "Location";
    String long_name "Longitude";
    String standard_name "longitude";
    String units "degrees_east";
  }
  heatwave_category {
    UInt32 _ChunkSizes 1, 1800, 3600;
    Byte _FillValue -5;
    String _Unsigned "true";
    Float64 colorBarMaximum 5.0;
    Float64 colorBarMinimum 0.0;
    String comment "This variable provides a measurement of daily sea surface temperature anomaly (SST Anomaly) based on an intensity classification algorithm for tracking marine heatwaves. Its value determines the contribution of the daily SST anomlay to the occurrence of a marine heatwave event and/or duration and intensity of an ongoing event. The value range is: 0 - No contribution to a marine heatwave event; 1 - Category I (Moderate); 2 - Category II (Strong); 3 - Category III (Severe); 4 - Category IV (Extreme); 5 - Category V (open-end beyond Extreme). Product description is provided at https://coralreefwatch.noaa.gov/product/marine_heatwave/index.php.";
    String flag_meanings "no_heatwave moderate strong severe extreme beyond_extreme";
    Byte flag_values 0, 1, 2, 3, 4, 5;
    String ioos_category "Temperature";
    String long_name "marine heatwave category";
    String units "1";
    Byte valid_max 5;
    Byte valid_min 0;
  }
  mask {
    UInt32 _ChunkSizes 1, 1800, 3600;
    Byte _FillValue -5;
    String _Unsigned "true";
    Float64 colorBarMaximum 4.0;
    Float64 colorBarMinimum 0.0;
    String flag_meanings "water land missing ice";
    Byte flag_values 0, 1, 2, 4;
    String ioos_category "Other";
    String long_name "pixel characteristics flag array";
    String units "1";
    Byte valid_max 4;
    Byte valid_min 0;
  }
  NC_GLOBAL {
    String _NCProperties "version=2,netcdf=4.7.4,hdf5=1.10.6";
    String acknowledgement "NOAA Coral Reef Watch (CRW)";
    String cdm_data_type "Grid";
    String comment "This is a product of the NOAA Coral Reef Watch Daily Global 5km Satellite Marine Heatwave Monitoring Product Suite Version 1.0.1, derived from CoralTemp v3.1.";
    String Conventions "CF-1.6, ACDD-1.3";
    String creator_email "coralreefwatch@noaa.gov";
    String creator_institution "NOAA Coral Reef Watch (CRW)";
    String creator_name "NOAA Coral Reef Watch (CRW)";
    String creator_type "institution";
    String creator_url "https://coralreefwatch.noaa.gov";
    String date_created "2019-11-19";
    String date_issued "2019-11-19";
    String date_metadata_modified "2024-07-18";
    String date_modified "2024-07-18";
    Float64 Easternmost_Easting 179.975;
    String geospatial_bounds "POLYGON ((-90 -180, 90 -180, 90 180, -90 180, -90 -180))";
    String geospatial_bounds_crs "EPSG:4326";
    Float64 geospatial_lat_max 89.975;
    Float64 geospatial_lat_min -89.975;
    Float64 geospatial_lat_resolution 0.049999999999999996;
    String geospatial_lat_units "degrees_north";
    Float64 geospatial_lon_max 179.975;
    Float64 geospatial_lon_min -179.975;
    Float64 geospatial_lon_resolution 0.049999999999999996;
    String geospatial_lon_units "degrees_east";
    String history 
"2021-09-22T12:00:00Z Initial version released: v1.0.
2021-09-22T12:00:00Z Version 1.0.1 released. Fixed minor compatibility issue loading data into GIS applications by altering dimension names and coordinate variable names.
2023-01-05T19:26:00Z Data obtained from NOAA Coral Reef Watch and re-distributed via THREDDS Data Server (TDS) at PacIOOS to provide temporal aggregation and distribution through NetCDF/OPeNDAP utilities like ncWMS and ERDDAP.
2024-07-18T19:00:00Z Due to changes in data format from NOAA Coral Reef Watch, time series aggregation is no longer possible with files before July 1, 2024.
2024-10-30T20:47:29Z (local files)
2024-10-30T20:47:29Z https://pae-paha.pacioos.hawaii.edu/griddap/mhw_5km.das";
    String id "Satellite_Daily_Global_5km_Marine_Heatwave_Category";
    String infoUrl "https://coralreefwatch.noaa.gov/product/marine_heatwave/";
    String institution "NOAA Coral Reef Watch (CRW)";
    String instrument "Earth Remote Sensing Instruments > Passive Remote Sensing > Spectrometers/Radiometers > Imaging Spectrometers/Radiometers > AHI > Advanced Himawari Imager, Earth Remote Sensing Instruments > Passive Remote Sensing > Spectrometers/Radiometers > Imaging Spectrometers/Radiometers > AVHRR > Advanced Very High Resolution Radiometer, Earth Remote Sensing Instruments > Passive Remote Sensing > Spectrometers/Radiometers > Imaging Spectrometers/Radiometers > GOES-13 Imager > Geostationary Operational Environmental Satellite 13-Imager, Earth Remote Sensing Instruments > Passive Remote Sensing > Spectrometers/Radiometers > Imaging Spectrometers/Radiometers > GOES-15 Imager > Geostationary Operational Environmental Satellite 15-Imager, Earth Remote Sensing Instruments > Passive Remote Sensing > Spectrometers/Radiometers > Imaging Spectrometers/Radiometers > SEVIRI > Spinning Enhanced Visible and Infrared Imager, Earth Remote Sensing Instruments > Passive Remote Sensing > Spectrometers/Radiometers > Imaging Spectrometers/Radiometers > VIIRS > Visible-Infrared Imager-Radiometer Suite";
    String instrument_vocabulary "GCMD Instrument Keywords";
    String ISO_Topic_Categories "oceans";
    String keywords "Earth Science > Climate Indicators > Atmospheric/Ocean Indicators > Extreme Weather > Heat/Cold Wave Frequency/Intensity, Earth Science > Oceans > Ocean Temperature > Sea Surface Temperature";
    String keywords_vocabulary "GCMD Science Keywords";
    String license "The data produced by Coral Reef Watch are available for use without restriction, but Coral Reef Watch relies on the ethics and integrity of the user to ensure that the source of the data and products is appropriately cited and credited. When using these data and products, credit and courtesy should be given to NOAA Coral Reef Watch. Please include the appropriate DOI associated with this dataset in the citation. For more information, visit the NOAA Coral Reef Watch website: https://coralreefwatch.noaa.gov. Recommendations for citing and providing credit are provided at https://coralreefwatch.noaa.gov/satellite/docs/recommendations_crw_citation.php. Users are referred to the footer section of the Coral Reef Watch website (https://coralreefwatch.noaa.gov/index.php) for disclaimers, policies, notices pertaining to the use of the data.";
    String locations "Geographic Region > Global Ocean";
    String locations_vocabulary "GCMD Location Keywords";
    String naming_authority "org.pacioos";
    Float64 Northernmost_Northing 89.975;
    String platform "Earth Observation Satellites > GOES (Geostationary Operational Environmental Satellite) > GOES-13, Earth Observation Satellites > GOES (Geostationary Operational Environmental Satellite) > GOES-15, Earth Observation Satellites > Himawari > Himawari Meteorological Satellites, Earth Observation Satellites > Joint Polar Satellite System (JPSS) > SUOMI-NPP > Suomi National Polar-orbiting Partnership, Earth Observation Satellites > METEOSAT > METEOSAT-8, Earth Observation Satellites > METEOSAT > METEOSAT-11, Earth Observation Satellites > METOP > METOP-B > Meteorological Operational Satellite - B";
    String platform_vocabulary "GCMD Platform Keywords";
    String processing_level "Level 4";
    String product_version "1.0.1";
    String program "NOAA Coral Reef Watch (CRW)";
    String project "NOAA Coral Reef Watch (CRW)";
    String publisher_email "info@pacioos.org";
    String publisher_institution "Pacific Islands Ocean Observing System (PacIOOS)";
    String publisher_name "Pacific Islands Ocean Observing System (PacIOOS)";
    String publisher_type "institution";
    String publisher_url "http://www.pacioos.hawaii.edu";
    String references "https://www.pacioos.hawaii.edu/metadata/mhw_5km.html; https://coralreefwatch.noaa.gov/product/marine_heatwave/; Related publication: Hobday AJ, Oliver ECJ, Sen Gupta A, Benthuysen JA, Burrows MT, Donat MG, Holbrook NJ, Moore PJ, Thomsen MS, Wernberg T, Smale DA. 2018. Categorizing and naming marine heatwaves. Oceanography 31, 2. https://doi.org/10.5670/oceanog.2018.205.";
    String source "satellite data";
    String sourceUrl "(local files)";
    Float64 Southernmost_Northing -89.975;
    String standard_name_vocabulary "CF Standard Name Table v39";
    String summary "Marine heatwaves are modelled off their terrestrial namesakes and are prolonged periods of anomalously high sea surface temperature (SST). In effect, they are categorized SST anomalies. They are also a more general version of the Coral Reef Watch (CRW) daily global 5km coral bleaching \"HotSpot\" product. Rather than being aimed specifically at corals, however, they provide a more generalized description of marine heat stress that is likely applicable to a broader range of marine life. This daily global 5km-resolution Marine Heatwave Watch (MHW) product is derived by applying the marine heatwave algorithm of Hobday et al. (2018) to the daily global 5km \"CoralTemp\" SST data product. CoralTemp is one of the best and most internally consistent daily global 5km SST products available, which allowed for the creation of an accurate climatology. This enabled the derivation of an accurate, consistent MHW product (comprised of near real-time and historic components), stretching back over three decades.";
    String testOutOfDate "now-60hours";
    String time_coverage_end "2024-10-29T12:00:00Z";
    String time_coverage_resolution "P1D";
    String time_coverage_start "2024-07-01T12:00:00Z";
    String title "NOAA Coral Reef Watch Daily Global 5-km Satellite Monitoring Marine Heatwave Watch";
    Float64 Westernmost_Easting -179.975;
  }
}

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.