Make A Graph

Dataset Title:	Ice Cover - 55-year Reanalysis 1957-present
Institution:	RSMC, Japan Meteorological Agency (Dataset ID: RSMC_seaice)
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 →

timeOffset (Hour)

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 {
    String _CoordinateAxisType "Time";
    Float64 actual_range -3.787128e+8, 1.6776072e+9;
    String axis "T";
    String calendar "proleptic_gregorian";
    String ioos_category "Time";
    String long_name "GRIB reference time";
    String source_name "reftime";
    String standard_name "time";
    String time_origin "01-JAN-1970 00:00:00";
    String units "seconds since 1970-01-01T00:00:00Z";
  }
  timeOffset {
    String _CoordinateAxisType "TimeOffset";
    Float64 actual_range 3.0, 6.0;
    String long_name "time offset from runtime";
    String standard_name "forecast_period";
    String udunits "Hour since 1957-12-31T18:00:00Z";
    String units "Hour";
  }
  latitude {
    String _CoordinateAxisType "Lat";
    Float32 actual_range -89.57009, 89.57009;
    String axis "Y";
    String gaussian_lats "true";
    String ioos_category "Location";
    String long_name "Latitude";
    String standard_name "latitude";
    String units "degrees_north";
  }
  longitude {
    String _CoordinateAxisType "Lon";
    Float32 actual_range 0.0, 359.438;
    String axis "X";
    String ioos_category "Location";
    String long_name "Longitude";
    String standard_name "longitude";
    String units "degrees_east";
  }
  Ice_cover_surface {
    Float64 colorBarMaximum 1.0;
    Float64 colorBarMinimum 0.0;
    String description "Ice cover";
    Int32 Grib1_Center 34;
    String Grib1_Interval_Name "Unknown Time Range Indicator -1";
    Int32 Grib1_Interval_Type -1;
    String Grib1_Level_Desc "Ground or water surface";
    Int32 Grib1_Level_Type 1;
    Int32 Grib1_Parameter 91;
    String Grib1_Parameter_Name "ICE_C";
    Int32 Grib1_Subcenter 241;
    Int32 Grib1_TableVersion 200;
    String Grib_Variable_Id "VAR_34-241-200-91_L1";
    String long_name "Ice cover @ Ground or water surface";
    Float32 missing_value NaN;
    String units "fraction";
  }
  NC_GLOBAL {
    String _CoordSysBuilder "ucar.nc2.dataset.conv.CF1Convention";
    String cdm_data_type "Grid";
    String Conventions "CF-1.6, COARDS, ACDD-1.3";
    String creator_name "RSMC, Japan Meteorological Agency";
    String creator_url "https://thredds.rda.ucar.edu/thredds/dodsC/aggregations/g/ds628.0/29/TwoD.html";
    Float64 Easternmost_Easting 359.438;
    String file_format "GRIB-1";
    String Generating_process_or_model "Japanese 55-year Reanalysis (JRA-55)";
    Float64 geospatial_lat_max 89.57009;
    Float64 geospatial_lat_min -89.57009;
    String geospatial_lat_units "degrees_north";
    Float64 geospatial_lon_max 359.438;
    Float64 geospatial_lon_min 0.0;
    Float64 geospatial_lon_resolution 0.5625007824726135;
    String geospatial_lon_units "degrees_east";
    String GRIB_table_version "0,200";
    String grid_mapping__CoordinateAxisTypes "Lat Lon";
    String grid_mapping__CoordinateTransformType "Projection";
    Float64 grid_mapping_earth_radius 6367470.0;
    String grid_mapping_name "latitude_longitude";
    String history 
"Read using CDM IOSP GribCollection v3
2024-11-06T09:38:01Z https://thredds.rda.ucar.edu/thredds/dodsC/aggregations/g/ds628.0/29/TwoD
2024-11-06T09:38:01Z https://er1.s4oceanice.eu/griddap/RSMC_seaice.das";
    String infoUrl "https://thredds.rda.ucar.edu/thredds/dodsC/aggregations/g/ds628.0/29/TwoD.html";
    String institution "RSMC, Japan Meteorological Agency";
    String keywords "agency, cover, data, ds628.0, ground, ice, Ice_cover_surface, japan, latitude, longitude, meteorological, rsmc, surface, thredds.rda.ucar.edu, time, timeoffset, twod, twod.das, water";
    String license "CC-BY 4.0";
    Float64 Northernmost_Northing 89.57009;
    String Originating_or_generating_Center "Tokyo (RSMC), Japan Meteorological Agency";
    String Originating_or_generating_Subcenter "Reanalysis project";
    String sourceUrl "https://thredds.rda.ucar.edu/thredds/dodsC/aggregations/g/ds628.0/29/TwoD";
    Float64 Southernmost_Northing -89.57009;
    String standard_name_vocabulary "CF Standard Name Table v70";
    String summary "Ice Cover - 55-year Reanalysis 1957-present, Japan Meteorological Agency data. Daily 3-Hourly and 6-Hourly Data/ Sea Ice Field";
    String time_coverage_end "2023-02-28T18:00:00Z";
    String time_coverage_start "1957-12-31T18:00:00Z";
    String title "Ice Cover - 55-year Reanalysis 1957-present";
    Float64 Westernmost_Easting 0.0;
  }
}

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.