Make A Graph

Dataset Title:	Sea Ice Concentration, AMSR2/VIIRS, Antarctic, 1km, Blended, UW-CIMSS, 2023- present, Daily
Institution:	Cooperative Institute for Meteorological Studies, University of Wisconsin at Madison (Dataset ID: nesdis_blendedsic_shem_daily)
Information:	Summary \| License \| Metadata \| Background \| Data Access Form \| Files

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Graph Type:
X Axis:
Y Axis:
Color:

Dimensions

Start

Stop

time (UTC)

specify just 1 value →

cols (meters)

rows (meters)

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

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Then set the File Type: (File Type information)
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[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 524288;
    String _CoordinateAxisType "Time";
    Float64 actual_range 1.7029872e+9, 1.71396e+9;
    String axis "T";
    String coverage_content_type "coordinate";
    String ioos_category "Time";
    String long_name "Time";
    String standard_name "time";
    String time_origin "01-JAN-1970 00:00:00";
    String units "seconds since 1970-01-01T00:00:00Z";
  }
  cols {
    UInt32 _ChunkSizes 8024;
    String _CoordinateAxisType "GeoX";
    Int32 actual_range -4012000, 4011000;
    String axis "X";
    String ioos_category "Location";
    String long_name "Projection Grid X Coordinates";
    String standard_name "projection_x_coordinate";
    String units "meters";
  }
  rows {
    UInt32 _ChunkSizes 8024;
    String _CoordinateAxisType "GeoY";
    Int32 actual_range -4012000, 4011000;
    String axis "Y";
    String ioos_category "Location";
    String long_name "Projection Grid Y Coordinates";
    String standard_name "projection_y_coordinate";
    String units "meters";
  }
  IceConc {
    UInt32 _ChunkSizes 1, 1003, 1003;
    Int16 _FillValue 999;
    Float64 colorBarMaximum 100.0;
    Float64 colorBarMinimum 0.0;
    String colorBarPalette "KT_ice";
    String comment "UW-CIMSS Experimental Blended Sea Ice Concentration derived from AMSR2 (NASA TEAM-2) and VIIRS (NDE)";
    String coordinates "time rows cols";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Ice Distribution";
    String long_name "Sea Ice Concentration, Blended AMSR2 and VIIRS";
    String standard_name "sea_ice_concentration";
    String units "percent";
    Int16 valid_range 0, 100;
  }
  NC_GLOBAL {
    String _NCProperties "version=2,netcdf=4.8.1,hdf5=1.10.6";
    String cdm_data_type "Grid";
    String cdr_program "NOAA National Environmental Satellite, Data and Information Service";
    String cdr_variable "fcdr_sea_ice_concentration_percentage";
    String Conventions "CF-1.6, ACDD-1.3, NOAA CDR v1.0, GDS v2.0, COARDS";
    String creator_email "rdworak@ssec.wisc.edu";
    String creator_name "Richard J. Dworak";
    String creator_type "institution";
    String creator_url "stratus.ssec.wisc.edu";
    String date_created "2024-04-25";
    String defaultGraphQuery "IceConc[(last)]&.draw=surface";
    String grid_mapping_comment "Data is stored in 1 km EASE2-Grid. Refer to https://nsidc.org/data/user-resources/help-center/guide-ease-grids";
    String grid_mapping_epsg_code "6932";
    String grid_mapping_latitude_of_projection_origin "-90.0f";
    String grid_mapping_longitude_of_projection_origin "0.0f";
    String grid_mapping_name "lambert_azimuthal_equal_area";
    String grid_mapping_proj4 "+proj=laea +lat_0=-90 +lon_0=0 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs +type=crs";
    String grid_mapping_proj4_params "+proj=laea +lat_0=-90 +lon_0=0 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs +type=crs";
    String grid_mappingearth_radius "6371228.0f";
    String grid_mappingfalse_easting "0.0f";
    String grid_mappingfalse_northing "0.0f";
    String history 
"2024-04-27T11:36:58Z (local files)
2024-04-27T11:36:58Z https://polarwatch.noaa.gov/griddap/nesdis_blendedsic_shem_daily.das";
    String id "Polar-AMSR2VIIRSBLEND_j01_v01r00_Shem";
    String infoUrl "https://www.mdpi.com/2072-4292/13/15/2982";
    String infourl "https://www.ospo.noaa.gov/Products/Suites/files/atbd/ATBD_IceSurfaceTemperatureIceConcentration_v1.0.pdf and https://ntrs.nasa.gov/api/citations/20140017491/downloads/20140017491.pdf";
    String institution "Cooperative Institute for Meteorological Studies, University of Wisconsin at Madison";
    String keywords "amsr2, antarctic, blended, cimss, cols, concentration, cooperative, cryosphere, data, distribution, earth, Earth Science > Blended Product > Amsr2 > Viirs, Earth Science > Cryosphere > Sea Ice > Sea Ice Concentration, ice, ice distribution, IceConc, imager, imager/radiometer, imaging, infrared, institute, madison, meteorological, product, radiometer, rows, science, sea, sea_ice_concentration, studies, suite, time, university, uw-cimss, viirs, visible, wisconsin";
    String keywords_vocabulary "GCMD Science Keywords";
    String license "These data may be redistributed and used without restriction.";
    String metadata_link "https://www.star.nesdis.noaa.gov/jpss/documents/ATBD/ATBD_EPS_Cloud_Mask_v1.2.pdf";
    String nameing_authority "ssec.wisc.edu";
    String platform "NOAA21 and GCOM-W1";
    String processing_level "L3 Mapped";
    String product_version "v1.0";
    String proj4_string "WGS84";
    String proj_crs_code "EPSG:6932";
    String references "https://www.mdpi.com/2072-4292/13/15/2982";
    String sensor "Visible Infrared Imaging Radiometer Suite (VIIRS) and The Advanced Microwave Scanning Radiometer 2 (AMSR2)";
    String source "AMSR2 and VIIRS";
    String sourceUrl "(local files)";
    String spatial_resolution "1 km";
    String standard_name_vocabulary "CF Standard Name Table v36";
    String summary "This is a Blended Sea Ice Concentration product that combines clear-sky Visible and Infrared Imager/Radiometer Suite (VIIRS) ice concentration from NOAA-20 with that comes from the AMSR2 NASA Team-2 10 km product. The output is remapped into 1-km EASE2 grid cells with a nominal resolution of at least 5-km. The NDE cloud mask is used to screen out cloudy VIIRS pixels. When the cloud mask for a data point is determined to be confidently clear, the output concentration in the blended product is 100% VIIRS. Otherwise, the Best Linear Unbiased Estimator equation is used to determine the output concentration (see https://www.sciencedirect.com/topics/mathematics/linear-unbiased-estimator#:~:text=Under%20assumptions%20V%20and%20VI,(Gauss%E2%80%93Markov%20theorem for more information on method).";
    String time_coverage_duration "P1D";
    String time_coverage_end "2024-04-24T12:00:00Z";
    String time_coverage_resolution "P1D";
    String time_coverage_start "2023-12-19T12:00:00Z";
    String title "Sea Ice Concentration, AMSR2/VIIRS, Antarctic, 1km, Blended, UW-CIMSS, 2023-present, Daily";
  }
}

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.