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Dataset Title:	X - Experimental LaRa (LaserRadar) snow depth 5 year mean using ESA algorithm, Arctic, 25km, 2018-2023.
Institution:	NOAA NESDIS STAR (Dataset ID: lara_snowdepth_5yrs_esa_nh)
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 →

ygrid (m)

xgrid (m)

Graph Settings
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Minimum:	Maximum:	N Sections:
Y Axis Minimum:	Maximum:

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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 {
    String _CoordinateAxisType "Time";
    Float64 actual_range 1.5157152e+9, 1.5445728e+9;
    String axis "T";
    String calendar "proleptic_gregorian";
    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";
  }
  ygrid {
    UInt32 _ChunkSizes 448;
    Float32 _FillValue NaN;
    Float32 actual_range -5337500.0, 5837500.0;
    String axis "Y";
    String ioos_category "Location";
    String long_name "Projection Grid Y Centers";
    String standard_name "projection_y_coordinate";
    String units "m";
    Float32 valid_range -5350000.0, 5850000.0;
  }
  xgrid {
    UInt32 _ChunkSizes 304;
    Float32 _FillValue NaN;
    Float32 actual_range -3837500.0, 3737500.0;
    String axis "X";
    String ioos_category "Location";
    String long_name "Projection Grid X Centers";
    String standard_name "projection_x_coordinate";
    String units "m";
    Float32 valid_range -3850000.0, 3750000.0;
  }
  LaRa_sd_5yr {
    UInt32 _ChunkSizes 1, 448, 304;
    Float64 _FillValue NaN;
    String coordinates "xgrid ygrid";
    String grid_mapping "projection";
    String ioos_category "Statistics";
    String long_name "LaRa Snow Depth 5yr mean";
    String units "meter";
  }
  grid_lat {
    Float64 _FillValue NaN;
    String coordinates "xgrid ygrid";
    String grid_mapping "projection";
    String ioos_category "Location";
    String long_name "Grid Lat";
  }
  grid_lon {
    Float64 _FillValue NaN;
    String ioos_category "Location";
    String long_name "Grid Lon";
  }
  NC_GLOBAL {
    String acknowledgement "Users are free to use the information hosted on this site in their research, provided credit is given to the NOAA / NESDIS Center for Satellite Applications and Research (STAR) Laboratory for Satellite Altimetry (LSA). Users are also asked to cite the following publication  whenever these data are used: Arctic snow depth and sea ice thickness from combined ICESat-2 and CryoSat-2 freeboard observations";
    String acknowledgment 
"Users are free to use the information hosted on this site in their research, 
\t\tprovided credit is given to the NOAA / NESDIS Center for Satellite Applications and Research (STAR) Laboratory 
\t\tfor Satellite Altimetry (LSA). Users are also asked to cite the following publication 
\t\twhenever these data are used: Arctic snow depth and sea ice thickness from combined ICESat-2 and CryoSat-2 freeboard observations";
    String cdm_data_type "Grid";
    String cdr_variable "LaRa_sd_5yr";
    String comment "Data use policy: In publications, presentations, or on web pages based on LSA data the following acknowledgment should be included: 'LaRa snow depth data are provided by NOAA Laboratory for Satellite Altimetry.'";
    String Conventions "CF-1.6, ACDD-1.3, COARDS";
    String creator_email "laurence dot connor at noaa.gov";
    String creator_name "NOAA NESDIS STAR";
    String creator_type "institution";
    String creator_url "https://www.star.nesdis.noaa.gov/socd/lsa/";
    String date_created "2024-01-01";
    String defaultGraphQuery "LaRa_sd_5yr[(last):(last)][(-5337500.0)][(3737500.0)]&.draw=surface";
    UInt32 grid_mapping__ChunkSizes 1;
    Float64 grid_mapping_false_easting 0.0;
    Float64 grid_mapping_false_northing 0.0;
    String grid_mapping_GeoTransform "-3850000.0 25000.0 0 5850000.0 0 -25000.0";
    Float64 grid_mapping_grid_boundary_bottom_projected_y -5350000.0;
    Float64 grid_mapping_grid_boundary_left_projected_x -3850000.0;
    Float64 grid_mapping_grid_boundary_right_projected_x 3750000.0;
    Float64 grid_mapping_grid_boundary_top_projected_y 5850000.0;
    Float64 grid_mapping_latitude_of_projection_origin 90.0;
    Float64 grid_mapping_longitude_of_projection_origin -45.0;
    String grid_mapping_name "polar_stereographic";
    Float64 grid_mapping_parent_grid_cell_column_subset_end 304.0;
    Float64 grid_mapping_parent_grid_cell_column_subset_start 0.0;
    Float64 grid_mapping_parent_grid_cell_row_subset_end 448.0;
    Float64 grid_mapping_parent_grid_cell_row_subset_start 0.0;
    String grid_mapping_proj4text "+proj=stere +lat_0=90 +lat_ts=70 +lon_0=-45 +k=1 +x_0=0 +y_0=0 +a=6378273 +b=6356889.449 +units=m +no_defs";
    Float64 grid_mapping_scaling_factor 1.0;
    Float64 grid_mapping_semimajor_radius 6378273.0;
    Float64 grid_mapping_semiminor_radius 6356889.449;
    String grid_mapping_spatial_ref "PROJCS[\"NSIDC Sea Ice Polar Stereographic North\",GEOGCS[\"Unspecified datum based upon the Hughes 1980 ellipsoid\",DATUM[\"Not_specified_based_on_Hughes_1980_ellipsoid\",SPHEROID[\"Hughes 1980\",6378273,298.279411123061,AUTHORITY[\"EPSG\",\"7058\"]],AUTHORITY[\"EPSG\",\"6054\"]],PRIMEM[\"Greenwich\",0,AUTHORITY[\"EPSG\",\"8901\"]],UNIT[\"degree\",0.01745329251994328,AUTHORITY[\"EPSG\",\"9122\"]],AUTHORITY[\"EPSG\",\"4054\"]],UNIT[\"metre\",1,AUTHORITY[\"EPSG\",\"9001\"]],PROJECTION[\"Polar_Stereographic\"],PARAMETER[\"latitude_of_origin\",70],PARAMETER[\"central_meridian\",-45],PARAMETER[\"scale_factor\",1],PARAMETER[\"false_easting\",0],PARAMETER[\"false_northing\",0],AUTHORITY[\"EPSG\",\"3411\"],AXIS[\"X\",UNKNOWN],AXIS[\"Y\",UNKNOWN]]";
    String grid_mapping_srid "urn:ogc:def:crs:EPSG::3411";
    Float64 grid_mapping_standard_parallel 70.0;
    Float64 grid_mapping_straight_vertical_longitude_from_pole 135.0;
    String grid_mapping_units "meters";
    String history 
"02/29/2024 V1 data file created
2025-04-01T10:11:59Z (local files)
2025-04-01T10:11:59Z https://polarwatch.noaa.gov/griddap/lara_snowdepth_5yrs_esa_nh.das";
    String infoUrl "https://www.star.nesdis.noaa.gov/socd/lsa/SeaIce/LaRaSnowDepth.php";
    String institution "NOAA NESDIS STAR";
    String keywords "5yr, alfred, america, arctic, atlantic, awi, barents, bay, beaufort, bering, canada, center, chukchi, common, concentration, continent, CONTINENT > NORTH AMERICA > CANADA > HUDSON BAY, Continent > North America > Canada > Hudson Bay, cryosphere, data, davis, defense, depth, dmsp, earth, Earth Science > Cryosphere > Sea Ice > Sea Ice Concentration, environmental, flight, format, geographic, Geographic Region > Arctic, Geographic Region > Northern Hemisphere, Geographic Region > Polar, goddard, gsfc, gulf, hemisphere, hudson, ice, information, instituite, lara, LaRa_sd_5yr, lawrence, marine, mayen, mean, meteorological, month, monthly, national, nesdis, network, noaa, north, northern, norwegian, nsidc, ocean, Ocean > Arctic Ocean, Ocean > Arctic Ocean > Barents Sea, Ocean > Arctic Ocean > Beaufort Sea, Ocean > Arctic Ocean > Chukchi Sea, Ocean > Atlantic Ocean > North Atlantic Ocean > Davis Straight, OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > GULF OF ST LAWRENCE, Ocean > Atlantic Ocean > North Atlantic Ocean > North Sea, Ocean > Atlantic Ocean > North Atlantic Ocean > Norwegian Sea, OCEAN > ATLANTIC OCEAN > NORTH ATLANTIC OCEAN > SVALBARD AND JAN MAYEN, Ocean > Pacific Ocean, Ocean > Pacific Ocean > North Pacific Ocean > Bering Sea, Ocean > Pacific Ocean > North Pacific Ocean > Sea Of Okhotsk, okhotsk, over, pacific, polar, program, region, research, satellite, science, sea, service, snow, space, star, statistics, straight, svalbard, time, wegener, xgrid, ygrid";
    String keywords_vocabulary "GCMD Science Keywords";
    String license "Creative Commons CC0 (CC 1.0)";
    String metadata_link "https://polarwatch.noaa.gov/erddap/lara_snowdepth_5yrs_nh/index.html";
    String platform "ICESat-2, CryoSat-2, Nimbus-7 SMMR, DMSP";
    String processing_level "NOAA Level 3";
    String product_version "v1";
    String program "NOAA/Laboratory for Satellite Altimetry";
    String proj_crs_code "EPSG:3411";
    String project "Arctic snow depth from combined ICESat-2 and Cryosat-2 freeboard observations";
    String references "To be submitted to Annals of Glaciology March, 2024";
    String sensor "Radar altimeter, Laser altimeter";
    String source "https://www.star.nesdis.noaa.gov/data/socd3/lsa/SeaIceProducts/LaRa/";
    String sourceUrl "(local files)";
    String spatial_resolution "25km";
    String standard_name_vocabulary "CF Standard Name Table v70";
    String summary "LaRa (LaserRadar) snow depth 5 year mean using ESA algorithm, Arctic, 25km, 2018-2023.";
    String time_coverage_duration "P5Y";
    String time_coverage_end "2018-12-12T00:00:00Z";
    String time_coverage_resolution "P5Y";
    String time_coverage_start "2018-01-12T00:00:00Z";
    String title "X - Experimental LaRa (LaserRadar) snow depth 5 year mean using ESA algorithm, Arctic, 25km, 2018-2023.";
  }
}

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.