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 data       graph     files  Sea Ice Concentration, NOAA/NSIDC Climate Data Record V4, Northern Hemisphere, 25km, Science
Quality, 1978-Present, Daily
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nsidcG02202v4nh1day

The Dataset's Variables and Attributes

Row Type Variable Name Attribute Name Data Type Value
attribute NC_GLOBAL _NCProperties String version=2,netcdf=4.8.1,hdf5=1.10.6
attribute NC_GLOBAL acknowledgement String This project was supported in part by a grant from the NOAA Climate Data Record Program. Production of original NASA Team and Bootstrap algorithm estimates supported by the NASA Polar Distributed Active Archive Center. The sea ice concentration algorithms were developed by Donald J. Cavalieri, Josefino C. Comiso, Claire L. Parkinson, and others at the NASA Goddard Space Flight Center in Greenbelt, MD.
attribute NC_GLOBAL cdm_data_type String Grid
attribute NC_GLOBAL cdr_variable String cdr_seaice_conc
attribute NC_GLOBAL contributor_name String Walter N. Meier, Florence Fetterer, Ann Windnagel, J. Scott Stewart, Trey Stafford, Matt Fisher
attribute NC_GLOBAL contributor_role String principal investigator, author, author, software developer, software developer, software developer
attribute NC_GLOBAL Conventions String CF-1.6, ACDD-1.3, COARDS
attribute NC_GLOBAL creator_email String nsidc at nsidc.org
attribute NC_GLOBAL creator_name String NSIDC
attribute NC_GLOBAL creator_type String institution
attribute NC_GLOBAL creator_url String https://nsidc.org/ (external link)
attribute NC_GLOBAL date_created String 2024-01-08T20:54:03Z
attribute NC_GLOBAL defaultGraphQuery String cdr_seaice_conc[last]%5B(-5337500.0)%5D%5B(3737500.0)%5D&.draw=surface
attribute NC_GLOBAL grid_mapping_false_easting double 0.0
attribute NC_GLOBAL grid_mapping_false_northing double 0.0
attribute NC_GLOBAL grid_mapping_GeoTransform String -3850000.0 25000.0 0 5850000.0 0 -25000.0
attribute NC_GLOBAL grid_mapping_grid_boundary_bottom_projected_y double -5350000.0
attribute NC_GLOBAL grid_mapping_grid_boundary_left_projected_x double -3850000.0
attribute NC_GLOBAL grid_mapping_grid_boundary_right_projected_x double 3750000.0
attribute NC_GLOBAL grid_mapping_grid_boundary_top_projected_y double 5850000.0
attribute NC_GLOBAL grid_mapping_latitude_of_projection_origin double 90.0
attribute NC_GLOBAL grid_mapping_longitude_of_projection_origin double -45.0
attribute NC_GLOBAL grid_mapping_name String polar_stereographic
attribute NC_GLOBAL grid_mapping_parent_grid_cell_column_subset_end double 304.0
attribute NC_GLOBAL grid_mapping_parent_grid_cell_column_subset_start double 0.0
attribute NC_GLOBAL grid_mapping_parent_grid_cell_row_subset_end double 448.0
attribute NC_GLOBAL grid_mapping_parent_grid_cell_row_subset_start double 0.0
attribute NC_GLOBAL grid_mapping_proj4text String +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
attribute NC_GLOBAL grid_mapping_scaling_factor double 1.0
attribute NC_GLOBAL grid_mapping_semimajor_radius double 6378273.0
attribute NC_GLOBAL grid_mapping_semiminor_radius double 6356889.449
attribute NC_GLOBAL grid_mapping_spatial_ref String 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]]
attribute NC_GLOBAL grid_mapping_srid String urn:ogc:def:crs:EPSG::3411
attribute NC_GLOBAL grid_mapping_standard_parallel double 70.0
attribute NC_GLOBAL grid_mapping_straight_vertical_longitude_from_pole double 135.0
attribute NC_GLOBAL grid_mapping_units String meters
attribute NC_GLOBAL history String Generated from NSIDC0001
attribute NC_GLOBAL id String https://doi.org/10.7265/sr8p-kc62 (external link)
attribute NC_GLOBAL infoUrl String https://nsidc.org/ (external link)
attribute NC_GLOBAL institution String NSIDC > National Snow and Ice Data Center
attribute NC_GLOBAL keywords String algorithm, america, arctic, area, atlantic, barents, bay, beaufort, bering, bootstrap, canada, cdr_seaice_conc, center, chukchi, climate, common, concentration, continent, CONTINENT > NORTH AMERICA > CANADA > HUDSON BAY, Continent > North America > Canada > Hudson Bay, cryosphere, daily, data, davis, day, defense, deviation, distribution, dmsp, earth, Earth Science > Cryosphere > Sea Ice > Ice Extent, Earth Science > Cryosphere > Sea Ice > Sea Ice Concentration, Earth Science > Oceans > Sea Ice > Ice Extent, estimated, extent, flag, flags, flight, format, fraction, geographic, Geographic Region > Arctic, Geographic Region > Northern Hemisphere, Geographic Region > Polar, goddard, gsfc, gulf, hemisphere, hudson, ice, ice distribution, interpolation, interpolation_flag, lawrence, mayen, melt, melt_onset_day_cdr_seaice_conc, meteorological, microwave, nasa, national, network, noaa, noaa/nsidc, north, northern, norwegian, nsidc, nsidc_bt_seaice_conc, nsidc_nt_seaice_conc, 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, oceans, okhotsk, onset, over, pacific, passive, polar, processed, program, qa_of_cdr_seaice_conc, quality, record, region, satellite, science, sea, sea_ice_area_fraction, sea_ice_area_fraction status_flag, snow, source, space, spatial, spatial_interpolation_flag, standard, statistics, status, stdev_of_cdr_seaice_conc, straight, svalbard, tdim, team, temporal, temporal_interpolation_flag, version
attribute NC_GLOBAL keywords_vocabulary String GCMD Science Keywords
attribute NC_GLOBAL license String No constraints on data access or use
attribute NC_GLOBAL metadata_Link String https://nsidc.org/data/g02202/versions/4/ (external link)
attribute NC_GLOBAL naming_authority String org.doi.dx
attribute NC_GLOBAL platform String DMSP 5D-3/F17 > Defense Meteorological Satellite Program-F17
attribute NC_GLOBAL processing_level String NOAA Level 3
attribute NC_GLOBAL product_version String v04r00
attribute NC_GLOBAL program String NOAA Climate Data Record Program
attribute NC_GLOBAL proj_crs_code String EPSG:3411
attribute NC_GLOBAL proj_crs_code_description String The proj_crs_code attribute references a registered projection identifier (i.e. EPSG) when available. If the projection is not registered, non-standard then this attribute references a PolarWatch assigned internal identifier.
attribute NC_GLOBAL project String NOAA/NSIDC passive microwave sea ice concentration climate data record
attribute NC_GLOBAL references String Comiso, J. C., and F. Nishio. 2008. Trends in the Sea Ice Cover Using Enhanced and Compatible AMSR-E, SSM/I, and SMMR Data. Journal of Geophysical Research 113, C02S07, doi:10.1029/2007JC0043257. ; Comiso, J. C., D. Cavalieri, C. Parkinson, and P. Gloersen. 1997. Passive Microwave Algorithms for Sea Ice Concentrations: A Comparison of Two Techniques. Remote Sensing of the Environment 60(3):357-84. ; Comiso, J. C. 1984. Characteristics of Winter Sea Ice from Satellite Multispectral Microwave Observations. Journal of Geophysical Research 91(C1):975-94. ; Cavalieri, D. J., P. Gloersen, and W. J. Campbell. 1984. Determination of Sea Ice Parameters with the NIMBUS-7 SMMR. Journal of Geophysical Research 89(D4):5355-5369. ; Cavalieri, D. J., C. l. Parkinson, P. Gloersen, J. C. Comiso, and H. J. Zwally. 1999. Deriving Long-term Time Series of Sea Ice Cover from Satellite Passive-Microwave Multisensor Data Sets. Journal of Geophysical Research 104(7): 15,803-15,814 ; Comiso, J.C., R.A. Gersten, L.V. Stock, J. Turner, G.J. Perez, and K. Cho. 2017. Positive Trend in the Antarctic Sea Ice Cover and Associated Changes in Surface Temperature. J. Climate, 30, 2251–2267, https://doi.org/10.1175/JCLI-D-16-0408.1
attribute NC_GLOBAL sensor String SSMI/S > Special Sensor Microwave Imager/Sounder
attribute NC_GLOBAL software_version_id String git@bitbucket.org:nsidc/seaice_cdr.git@c9c632e73530554d8acfac9090baeb1e35755897
attribute NC_GLOBAL source String Generated from NSIDC0001
attribute NC_GLOBAL sourceUrl String (local files)
attribute NC_GLOBAL spatial_resolution String 25km
attribute NC_GLOBAL standard_name_vocabulary String CF Standard Name Table v70
attribute NC_GLOBAL summary String This data set provides a passive microwave sea ice concentration climate data record (CDR) based on gridded brightness temperatures (TBs) from the Defense Meteorological Satellite Program (DMSP) series of passive microwave radiometers: the Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR), the Special Sensor Microwave Imager (SSM/I) and the Special Sensor Microwave Imager/Sounder (SSMIS). The sea ice concentration CDR is an estimate of sea ice concentration that is produced by combining concentration estimates from two algorithms developed at the NASA Goddard Space Flight Center (GSFC): the NASA Team algorithm and the Bootstrap algorithm. The individual algorithms are used to process and combine brightness temperature data at National Snow and Ice Data Center (NSIDC). This product is designed to provide a consistent time series of sea ice concentrations (the fraction, or percentage, of ocean area covered by sea ice) from November 1978 to the present which spans the coverage of several passive microwave instruments. The data are gridded on the NSIDC polar stereographic grid with 25 x 25 km grid cells, and are available in Network Common Data Format (NetCDF) file format. Each file contains a variable with the CDR concentration values as well as variables that hold the NASA Team and Bootstrap processed concentrations for reference Variables containing standard deviation, quality flags, and projection information are also included. Data are available from NSIDC via FTP see https://nsidc.org/data/G02202/versions/4/. Data are also distributed via the PolarWatch ERDDAP at https://polarwatch.noaa.gov/erddap. Note that the data format available through PolarWatch is different from the NSIDC FTP NetCDF files. The PolarWatch data server stores projection information as global attributes (with the prefix grid_mapping) instead of as a variable; and the timestamp is served in different units (seconds since 1970).
attribute NC_GLOBAL time_coverage_duration String P1D
attribute NC_GLOBAL time_coverage_end String 2023-09-30T00:00:00Z
attribute NC_GLOBAL time_coverage_resolution String P1D
attribute NC_GLOBAL time_coverage_start String 1978-10-25T00:00:00Z
attribute NC_GLOBAL title String Sea Ice Concentration, NOAA/NSIDC Climate Data Record V4, Northern Hemisphere, 25km, Science Quality, 1978-Present, Daily
dimension time   double nValues=16324, evenlySpaced=false, averageSpacing=1 day 0h 7m 46s
attribute time _ChunkSizes uint 1024
attribute time _CoordinateAxisType String Time
attribute time actual_range double 2.781216E8, 1.696032E9
attribute time axis String T
attribute time calendar String gregorian
attribute time ioos_category String Time
attribute time long_name String Time
attribute time standard_name String time
attribute time time_origin String 01-JAN-1970 00:00:00
attribute time units String seconds since 1970-01-01T00:00:00Z
dimension ygrid   float nValues=448, evenlySpaced=true, averageSpacing=-25000.0
attribute ygrid _ChunkSizes uint 448
attribute ygrid actual_range float -5337500.0, 5837500.0
attribute ygrid axis String Y
attribute ygrid ioos_category String Location
attribute ygrid long_name String projection_grid_y_centers
attribute ygrid standard_name String projection_y_coordinate
attribute ygrid units String meters
attribute ygrid valid_range float -5350000.0, 5850000.0
dimension xgrid   float nValues=304, evenlySpaced=true, averageSpacing=25000.0
attribute xgrid _ChunkSizes uint 304
attribute xgrid actual_range float -3837500.0, 3737500.0
attribute xgrid axis String X
attribute xgrid ioos_category String Location
attribute xgrid long_name String projection_grid_x_centers
attribute xgrid standard_name String projection_x_coordinate
attribute xgrid units String meters
attribute xgrid valid_range float -3850000.0, 3750000.0
variable cdr_seaice_conc   float time, ygrid, xgrid
attribute cdr_seaice_conc _FillValue float 2.54
attribute cdr_seaice_conc ancillary_variables String stdev_of_cdr_seaice_conc qa_of_cdr_seaice_conc
attribute cdr_seaice_conc colorBarMaximum double 1.0
attribute cdr_seaice_conc colorBarMinimum double 0.0
attribute cdr_seaice_conc colorBarPalette String KT_ice
attribute cdr_seaice_conc datum String +ellps=urn:ogc:def:crs:EPSG::4326
attribute cdr_seaice_conc flag_meanings String pole_hole lakes coastal land_mask missing_data
attribute cdr_seaice_conc flag_values ubyte 251, 252, 253, 254, 255
attribute cdr_seaice_conc ioos_category String Ice Distribution
attribute cdr_seaice_conc long_name String NOAA/NSIDC Climate Data Record of Passive Microwave Daily Northern Hemisphere Sea Ice Concentration
attribute cdr_seaice_conc references String https://nsidc.org/data/g02202/versions/4/ (external link)
attribute cdr_seaice_conc standard_name String sea_ice_area_fraction
attribute cdr_seaice_conc units String 1
attribute cdr_seaice_conc valid_range float 0.0, 1.0
variable melt_onset_day_cdr_seaice_conc   ubyte time, ygrid, xgrid
attribute melt_onset_day_cdr_seaice_conc _FillValue ubyte 255
attribute melt_onset_day_cdr_seaice_conc colorBarMaximum double 250.0
attribute melt_onset_day_cdr_seaice_conc colorBarMinimum double 50.0
attribute melt_onset_day_cdr_seaice_conc datum String +ellps=urn:ogc:def:crs:EPSG::4326
attribute melt_onset_day_cdr_seaice_conc ioos_category String Ice Distribution
attribute melt_onset_day_cdr_seaice_conc long_name String Day of Snow Melt Onset Over Sea Ice
attribute melt_onset_day_cdr_seaice_conc missing_value ubyte 255
attribute melt_onset_day_cdr_seaice_conc units String 1
attribute melt_onset_day_cdr_seaice_conc valid_range ubyte 60, 244
variable nsidc_bt_seaice_conc   float time, ygrid, xgrid
attribute nsidc_bt_seaice_conc _FillValue float 2.54
attribute nsidc_bt_seaice_conc colorBarMaximum double 1.0
attribute nsidc_bt_seaice_conc colorBarMinimum double 0.0
attribute nsidc_bt_seaice_conc colorBarPalette String KT_ice
attribute nsidc_bt_seaice_conc datum String +ellps=urn:ogc:def:crs:EPSG::4326
attribute nsidc_bt_seaice_conc flag_meanings String pole_hole unused coastal land_mask missing_data
attribute nsidc_bt_seaice_conc flag_values ubyte 251, 252, 253, 254, 255
attribute nsidc_bt_seaice_conc ioos_category String Ice Distribution
attribute nsidc_bt_seaice_conc long_name String Passive Microwave Daily Northern Hemisphere Sea Ice Concentration by Bootstrap algorithm processed by NSIDC
attribute nsidc_bt_seaice_conc standard_name String sea_ice_area_fraction
attribute nsidc_bt_seaice_conc units String 1
attribute nsidc_bt_seaice_conc valid_range float 0.0, 1.0
variable nsidc_nt_seaice_conc   float time, ygrid, xgrid
attribute nsidc_nt_seaice_conc _FillValue float 2.54
attribute nsidc_nt_seaice_conc colorBarMaximum double 1.0
attribute nsidc_nt_seaice_conc colorBarMinimum double 0.0
attribute nsidc_nt_seaice_conc colorBarPalette String KT_ice
attribute nsidc_nt_seaice_conc datum String +ellps=urn:ogc:def:crs:EPSG::4326
attribute nsidc_nt_seaice_conc flag_meanings String pole_hole unused coastal land_mask missing_data
attribute nsidc_nt_seaice_conc flag_values ubyte 251, 252, 253, 254, 255
attribute nsidc_nt_seaice_conc ioos_category String Ice Distribution
attribute nsidc_nt_seaice_conc long_name String Passive Microwave Daily Northern Hemisphere Sea Ice Concentration by NASA Team algorithm processed by NSIDC
attribute nsidc_nt_seaice_conc standard_name String sea_ice_area_fraction
attribute nsidc_nt_seaice_conc units String 1
attribute nsidc_nt_seaice_conc valid_range float 0.0, 1.0
variable qa_of_cdr_seaice_conc   ubyte time, ygrid, xgrid
attribute qa_of_cdr_seaice_conc _FillValue ubyte 0
attribute qa_of_cdr_seaice_conc colorBarMaximum double 64.0
attribute qa_of_cdr_seaice_conc colorBarMinimum double 0.0
attribute qa_of_cdr_seaice_conc colorBarPalette String KT_amp
attribute qa_of_cdr_seaice_conc datum String +ellps=urn:ogc:def:crs:EPSG::4326
attribute qa_of_cdr_seaice_conc flag_mask_meanings String BT_weather_filter_applied NT_weather_filter_applied BT_land_spillover_filter_applied NT_land_spillover_filter_applied valid_ice_mask_applied spatial_interpolation_applied temporal_interpolation_applied melt_start_detected
attribute qa_of_cdr_seaice_conc flag_masks ubyte 1, 2, 4, 8, 16, 32, 64, 128
attribute qa_of_cdr_seaice_conc ioos_category String Quality
attribute qa_of_cdr_seaice_conc long_name String Passive Microwave Daily Northern Hemisphere Sea Ice Concentration QC flags
attribute qa_of_cdr_seaice_conc missing_value ubyte 0
attribute qa_of_cdr_seaice_conc standard_name String sea_ice_area_fraction status_flag
attribute qa_of_cdr_seaice_conc valid_range ubyte 1, 255
variable spatial_interpolation_flag   ubyte time, ygrid, xgrid
attribute spatial_interpolation_flag _FillValue ubyte 0
attribute spatial_interpolation_flag colorBarMaximum double 32.0
attribute spatial_interpolation_flag colorBarMinimum double 0.0
attribute spatial_interpolation_flag colorBarPalette String KT_amp
attribute spatial_interpolation_flag datum String +ellps=urn:ogc:def:crs:EPSG::4326
attribute spatial_interpolation_flag flag_masks ubyte 1, 2, 4, 8, 16, 32
attribute spatial_interpolation_flag flag_meanings String 19v_tb_value_interpolated 19h_tb_value_interpolated 22v_tb_value_interpolated 37v_tb_value_interpolated 37h_tb_value_interpolated pole_hole_value_interpolated
attribute spatial_interpolation_flag ioos_category String Quality
attribute spatial_interpolation_flag long_name String Passive Microwave Daily Northern Hemisphere Sea Ice Concentration spatial interpolation flags
attribute spatial_interpolation_flag missing_value ubyte 0
attribute spatial_interpolation_flag standard_name String interpolation_flag
attribute spatial_interpolation_flag valid_range ubyte 0, 63
variable stdev_of_cdr_seaice_conc   float time, ygrid, xgrid
attribute stdev_of_cdr_seaice_conc _FillValue float -1.0
attribute stdev_of_cdr_seaice_conc colorBarMaximum double 5.0
attribute stdev_of_cdr_seaice_conc colorBarMinimum double 0.0
attribute stdev_of_cdr_seaice_conc colorBarPalette String KT_amp
attribute stdev_of_cdr_seaice_conc datum String +ellps=urn:ogc:def:crs:EPSG::4326
attribute stdev_of_cdr_seaice_conc flag_meanings String pole_hole lakes coastal land_mask missing_data
attribute stdev_of_cdr_seaice_conc flag_values ubyte 251, 252, 253, 254, 255
attribute stdev_of_cdr_seaice_conc ioos_category String Statistics
attribute stdev_of_cdr_seaice_conc long_name String Passive Microwave Daily Northern Hemisphere Sea Ice Concentration Source Estimated Standard Deviation
attribute stdev_of_cdr_seaice_conc missing_value float -1.0
attribute stdev_of_cdr_seaice_conc valid_range float 0.0, 100.0
variable temporal_interpolation_flag   ubyte time, ygrid, xgrid
attribute temporal_interpolation_flag _FillValue ubyte 0
attribute temporal_interpolation_flag colorBarMaximum double 60.0
attribute temporal_interpolation_flag colorBarMinimum double 0.0
attribute temporal_interpolation_flag colorBarPalette String KT_amp
attribute temporal_interpolation_flag comment String If flagged, the value has been replaced by the value n-days prior, n-days following, or the mean of n-days prior and following where n is 1, 2, 3, 4, or 5 days.
attribute temporal_interpolation_flag datum String +ellps=urn:ogc:def:crs:EPSG::4326
attribute temporal_interpolation_flag flag_masks ubyte 1, 2, 3, 4, 5, 10, 11, 20, 22, 30, 33, 40, 44, 50, 55
attribute temporal_interpolation_flag flag_meanings String 1_day_following 2_days_following 3_days_following 4_days_following 5_days_following 1_day_prior mean_of_prior_and_following_1_day 2_days_prior mean_of_prior_and_following_2_days 3_days_prior mean_of_prior_and_following_3_days 4_days_prior mean_of_prior_and_following_4_days 5_days_prior mean_of_prior_and_following_5_days
attribute temporal_interpolation_flag ioos_category String Quality
attribute temporal_interpolation_flag long_name String Passive Microwave Daily Northern Hemisphere Sea Ice Concentration temporal interpolation flags
attribute temporal_interpolation_flag missing_value ubyte 0
attribute temporal_interpolation_flag standard_name String interpolation_flag
attribute temporal_interpolation_flag valid_range ubyte 0, 55

The information in the table above is also available in other file formats (.csv, .htmlTable, .itx, .json, .jsonlCSV1, .jsonlCSV, .jsonlKVP, .mat, .nc, .nccsv, .tsv, .xhtml) via a RESTful web service.


 
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