NOAA PolarWatch ERDDAP
Easier access to scientific data
   
Brought to you by NOAA NMFS SWFSC ERD    

ERDDAP > griddap > Data Access Form ?

Dataset Title:  Sea Ice Thickness, Extended AVHRR Polar Pathfinder APP-X NCEI Climate Data
Record V2, Arctic, 1982-Present, Twice Daily
Subscribe RSS
Institution:  NOAA/NCEI   (Dataset ID: ncei_polarAPPX20_nhem)
Information:  Summary ? | License ? | Metadata | Background (external link) | Files | Make a graph
 
Dimensions ? Start ? Stride ? Stop ?  Size ?    Spacing ?
 time (UTC) ?      26714    12h 8m 28s (uneven)
  < slider >
 rows (meters) ?      361    25067.53 (even)
  < slider >
 columns (meters) ?      361    25067.53 (even)
  < slider >
 
Grid Variables (which always also download all of the dimension variables)
 cdr_sea_ice_thickness (m) ?
 cdr_surface_temperature (degree_K) ?
 cdr_surface_albedo (NOAA CDR of surface broadband albedo, 1) ?
 cdr_surface_downwelling_shortwave_flux (W m-2) ?
 cdr_surface_downwelling_longwave_flux (W m-2) ?
 cdr_surface_upwelling_shortwave_flux (W m-2) ?
 cdr_surface_upwelling_longwave_flux (W m-2) ?
 cdr_cloud_binary_mask (1) ?
 cdr_toa_net_downward_shortwave_flux (W m-2) ?
 cdr_toa_outgoing_shortwave_flux (W m-2) ?
 cdr_toa_outgoing_longwave_flux (W m-2) ?
 surface_type (1) ?
 cloud_particle_phase (1) ?
 cloud_particle_radius (microns) ?
 cloud_optical_depth (1) ?
 cloud_top_pressure (hPa) ?
 cloud_top_temperature (K) ?
 cloud_type (1) ?
 surface_shortwave_cloud_radiative_forcing (W m-2) ?
 surface_longwave_cloud_radiative_forcing (W m-2) ?

File type: (more info)

(Documentation / Bypass this form) ?
 
(Please be patient. It may take a while to get the data.)


 

The Dataset Attribute Structure (.das) for this Dataset

Attributes {
  time {
    Int32 _ChunkSizes 524288;
    String _CoordinateAxisType "Time";
    Float64 actual_range 3.787056e+8, 1.5462648e+9;
    String axis "T";
    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";
  }
  rows {
    String _CoordinateAxisType "GeoY";
    Float32 actual_range -4499620.0, 4524689.0;
    String axis "Y";
    String comment "columns values are the upper left of the grid cells";
    String ioos_category "Location";
    String long_name "Projection Grid Y Coordinates";
    String standard_name "projection_y_coordinate";
    String units "meters";
  }
  columns {
    String _CoordinateAxisType "GeoX";
    Float32 actual_range -4524688.0, 4499621.0;
    String axis "X";
    String comment "columns values are the upper left of the grid cells";
    String ioos_category "Location";
    String long_name "Projection Grid X Coordinates";
    String standard_name "projection_x_coordinate";
    String units "meters";
  }
  cdr_sea_ice_thickness {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_ice";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Ice Distribution";
    String long_name "NOAA CDR of sea ice thickness";
    String standard_name "sea_ice_thickness";
    String units "m";
    Float32 valid_range 0.0, 10.0;
  }
  cdr_surface_temperature {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_thermal";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Temperature";
    String long_name "NOAA CDR of surface skin temperature";
    String standard_name "surface_temperature";
    String units "degree_K";
    Float32 valid_range 0.0, 1000.0;
  }
  cdr_surface_albedo {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_solar";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "NOAA CDR of surface broadband albedo";
    String standard_name "surface_albedo";
    String units "1";
    Float32 valid_range 0.0, 1.0;
  }
  cdr_surface_downwelling_shortwave_flux {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_solar";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "NOAA CDR of surface downwelling shortwave radiative flux";
    String standard_name "surface_downwelling_shortwave_flux";
    String units "W m-2";
    Float32 valid_range 0.0, 1800.0;
  }
  cdr_surface_downwelling_longwave_flux {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_solar";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "NOAA CDR of surface downwelling longwave radiative flux";
    String standard_name "surface_downwelling_longwave_flux";
    String units "W m-2";
    Float32 valid_range 0.0, 1800.0;
  }
  cdr_surface_upwelling_shortwave_flux {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_solar";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "NOAA CDR of surface upwelling shortwave radiative flux";
    String standard_name "surface_upwelling_shortwave_flux";
    String units "W m-2";
    Float32 valid_range 0.0, 1800.0;
  }
  cdr_surface_upwelling_longwave_flux {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_solar";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "NOAA CDR of surface upwelling longwave radiative flux";
    String standard_name "surface_upwelling_longwave_flux";
    String units "W m-2";
    Float32 valid_range 0.0, 1800.0;
  }
  cdr_cloud_binary_mask {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 199.0;
    String colorBarContinuous "false";
    Float64 colorBarMaximum 1.5;
    Float64 colorBarMinimum -0.5;
    String colorBarNSections "2";
    String colorBarPalette "BlackWhite";
    String coordinates "longitude latitude time";
    String coverage_content_type "referenceInformation";
    String flag_meanings "clear cloudy";
    Int16 flag_values 0, 1;
    String grid_mapping "crs";
    String ioos_category "Identifier";
    String long_name "NOAA CDR of cloud mask";
    String units "1";
    Float32 valid_range 0.0, 1.0;
  }
  cdr_toa_net_downward_shortwave_flux {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_solar";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "NOAA CDR of TOA net downward shortwave radiative flux";
    String standard_name "toa_net_downward_shortwave_flux";
    String units "W m-2";
    Float32 valid_range 0.0, 1800.0;
  }
  cdr_toa_outgoing_shortwave_flux {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_solar";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "NOAA CDR of TOA outgoing shortwave radiative flux";
    String standard_name "toa_outgoing_shortwave_flux";
    String units "W m-2";
    Float32 valid_range 0.0, 1800.0;
  }
  cdr_toa_outgoing_longwave_flux {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_solar";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "NOAA CDR of TOA outgoing longwave radiative flux";
    String standard_name "toa_outgoing_longwave_flux";
    String units "W m-2";
    Float32 valid_range 0.0, 1800.0;
  }
  surface_type {
    Int32 _ChunkSizes 1, 361, 361;
    Int16 _FillValue 255;
    String colorBarContinuous "false";
    Float64 colorBarMaximum 5.5;
    Float64 colorBarMinimum -0.5;
    String colorBarNSections "6";
    String colorBarPalette "KT_gray";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String flag_meanings "not_land ice snow land";
    Int16 flag_values 0, 3, 4, 254;
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "surface type";
    String units "1";
    Int16 valid_range 0, 254;
  }
  cloud_particle_phase {
    Int32 _ChunkSizes 1, 361, 361;
    Int16 _FillValue 199;
    String colorBarContinuous "false";
    Float64 colorBarMaximum 1.5;
    Float64 colorBarMinimum -0.5;
    String colorBarNSections "2";
    String colorBarPalette "KT_haline";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String flag_meanings "liquid solid";
    Int16 flag_values 0, 1;
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "cloud particle phase";
    String units "1";
    Int16 valid_range 0, 1;
  }
  cloud_particle_radius {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_haline";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "cloud particle radius";
    String units "microns";
    Float32 valid_range 0.0, 300.0;
  }
  cloud_optical_depth {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_deep";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "cloud optical depth";
    String units "1";
    Float32 valid_range 0.0, 300.0;
  }
  cloud_top_pressure {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_dense";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "cloud top pressure";
    String units "hPa";
    Float32 valid_range 0.0, 1000.0;
  }
  cloud_top_temperature {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_thermal";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "cloud top temperature";
    String units "K";
    Float32 valid_range 0.0, 1000.0;
  }
  cloud_type {
    Int32 _ChunkSizes 1, 361, 361;
    Int16 _FillValue 199;
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "cloud type";
    String meanings "Cloud type value has two digits, i.e. XX, the ones place X (the first X from left), representing cloud type from CASPR algorithm, and the tenth place X representing cloud type from CLAVR algorithm. For CLAVR algorithm the tenth place X meanings: 0=clear or partly cloudy,1=fogs,2=liquid,3=mixed phase,4=glaciated,5=cirrus6=cirrus over lower,7=unused,8=unused,9=missing. For CASPR algorithm the ones place X meanings: 0=clear,1=cirrus,2=low stratus,3=warm,4=cold,5=water6=ice,7=Polar stratospheric cloud (PSC),8=unknown,9=missing.";
    String units "1";
    Int16 valid_range 0, 99;
  }
  surface_shortwave_cloud_radiative_forcing {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_dense";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "surface shortwave cloud radiative forcing";
    String units "W m-2";
    Float32 valid_range 0.0, 1800.0;
  }
  surface_longwave_cloud_radiative_forcing {
    Int32 _ChunkSizes 1, 361, 361;
    Float32 _FillValue 9999.0;
    String colorBarPalette "KT_dense";
    String coordinates "longitude latitude time";
    String coverage_content_type "physicalMeasurement";
    String grid_mapping "crs";
    String ioos_category "Meteorology";
    String long_name "surface longwave cloud radiative forcing";
    String units "W m-2";
    Float32 valid_range 0.0, 1800.0;
  }
  NC_GLOBAL {
    String acknowledgement "Please acknowledge NCEI, CoastWatch West Coast Node, and this dataset (doi:10.25921/AE96-0E57).";
    String cdm_data_type "Grid";
    String cdr_program "NOAA Climate Data Record Program for satellites";
    String cdr_variable "cdr_surface_temperature, cdr_surface_albedo, cdr_surface_downwelling_shortwave_flux, cdr_surface_downwelling_longwave_flux, cdr_surface_upwelling_shortwave_flux, cdr_surface_upwelling_longwave_flux, cdr_cloud_binary_mask, cdr_sea_ice_thickness, cdr_toa_net_downward_shortwave_flux, cdr_toa_outgoing_shortwave_flux, cdr_toa_outgoing_longwave_flux,surface_type, cloud_particle_phase, cloud_particle_radius, cloud_optical_depth, cloud_top_pressure, cloud_top_temperature, Cloud_type, surface_shortwave_cloud_radiative_forcing, surface_longwave_cloud_radiative_forcing";
    String comment "In order to be compliant with the EASE Grid specifications, the following modifications were made to the source files: 1) For each data variable plus the latitude and longitude variables, the two dimensional x-y grid was rotated clockwise by 90 degrees, resulting in geographical orientation where the Greenwich Meridian runs parallel to the y (rows)-axis from the North Pole at the grid center to the middle of the x (columns)-axis at the bottom edge of the grid and -90 degree E meridian runs parallel to the x (columns)-axis from the North Pole at the grid center to the middle of the y (rows)-axis at the left edge of the grid.: 2) two coordinate variables (columns and rows) were added that correspond to the columns and rows dimensions (units of m). In addition, the time variable was modified to put all of the files in the dataset on the same base time (seconds since 1970-01-01T00:00:00Z).";
    String Conventions "COARDS, CF-1.4, Unidata Dataset Discovery v1.0";
    String creator_email "erd.data@noaa.gov";
    String creator_name "NOAA/NMFS/SWFSC/ERD and NOAA/NESDIS/CoastWatch West Coast Node";
    String creator_type "institution";
    String date_created "2019-06-25";
    String defaultGraphQuery "cdr_sea_ice_thickness[(last)][(-4499620.5):(4524688.5)][(-4524688.5):(4499620.5)]&.draw=surface";
    String doi "doi.org/10.25921/AE96-0E57";
    String EPSG "http://epsg.io/3408";
    String history 
"Data files were obtained from NCEI at https://www.ncei.noaa.gov/data/avhrr-polar-pathfinder-extended/access/. For each data variable plus the latitude and longitude variables, the two dimensional x-y grid was rotated clockwise by 90 degrees, resulting in geographical orientation where the Greenwich Meridian runs parallel to the y (rows)-axis from the North Pole at the grid center to the middle of the x (columns)-axis at the bottom edge of the grid and -90 degree E meridian runs parallel to the x (columns)-axis from the North Pole at the grid center to the middle of the y (rows)-axis at the left edge of the grid. To coordinate variables (columns and rows) were added that correspond to the columns and rows dimensions. The coordinate variables have units of meters. The timestamp was made consistent across all files by converting to seconds since 1970-01-01T00:00:00Z. Metadata were alter to be in compliance with CF and ACDD standards.
2021-09-17T19:33:07Z https://www.ncei.noaa.gov/metadata/geoportal/rest/metadata/item/gov.noaa.ncdc:C00941/html
2021-09-17T19:33:07Z https://polarwatch.noaa.gov/erddap/griddap/ncei_polarAPPX20_nhem.das";
    String id "Polar-APP-X_v02r00_Nhem";
    String infoUrl "https://www.ncei.noaa.gov/metadata/geoportal/rest/metadata/item/gov.noaa.ncdc:C00941/html";
    String institution "NOAA/NCEI";
    String keywords "Earth Science > Atmosphere > Atmospheric Radiation > Longwave Radiation, Earth Science > Atmosphere > Atmospheric Radiation > Radiative Flux, Earth Science > Atmosphere > Atmospheric Radiation > Solar Radiation, Earth Science > Atmosphere > Clouds > Cloud Microphysics > Cloud Droplet Concentration(Size), Earth Science > Atmosphere > Clouds > Cloud Microphysics > Cloud Droplet Phase, Earth Science > Atmosphere > Clouds > Cloud Microphysics > Cloud Optical Depth(Thickness), Earth Science > Atmosphere > Clouds > Cloud Properties > Cloud Fraction, Earth Science > Atmosphere > Clouds > Cloud Properties > Cloud Top Pressure, Earth Science > Atmosphere > Clouds > Cloud Properties > Cloud Top Temperature, Earth Science > Atmosphere > Clouds > Cloud Properties > Cloud Type, Earth Science > Atmosphere > Clouds > Cloud Radiative Transfer > Cloud Radiative Forcing, Earth Science > Climate Indicators > Cryospheric Indicators > Ice Depth(Thickness), Earth Science > Cryosphere > Sea Ice > Ice Depth(Thickness), Earth Science > Cryosphere > Snow And Ice > Albedo, Earth Science > Cryosphere > Snow And Ice > Snow And Ice Temperature, Earth Science > Land Surface > Land Albedo, Earth Science > Land Surface > Land Temperature, Earth Science > Oceans > Sea Ice > Ice Depth(Thickness), Earth Science > Terrestrial Hydrosphere > Snow And Ice > Albedo, Earth Science > Terrestrial Hydrosphere > Snow And Ice > Ice Depth(Thickness)";
    String keywords_vocabulary "NASA Global Change Master Directory (GCMD) Earth Science Keywords, Version 8";
    String license 
"The data may be used and redistributed for free but is not intended
for legal use, since it may contain inaccuracies. Neither the data
Contributor, ERD, NOAA, nor the United States Government, nor any
of their employees or contractors, makes any warranty, express or
implied, including warranties of merchantability and fitness for a
particular purpose, or assumes any legal liability for the accuracy,
completeness, or usefulness, of this information.";
    String Metadata_Conventions "COARDS, CF-1.6, Unidata Dataset Discovery v1.0";
    String metadata_link "https://doi.org/10.25921/AE96-0E57";
    String naming_authority "gov.noaa.ncei";
    String NCO "\"4.6.3\"";
    Int32 nco_openmp_thread_number 1;
    String platform " NOAA polar orbiting satellite 19";
    String product_version "V2.0";
    String PROJ4 "+proj=laea +lat_0=90 +lon_0=0 +x_0=0 +y_0=0 +a=6371228 +b=6371228 +units=m +no_defs";
    String proj_crs_code "EPSG:3408";
    String proj_crs_code_description "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.";
    String proj_units "meters";
    String publisher_email "erd.data@noaa.gov";
    String publisher_name "NOAA/NMFS/SWFSC/ERD and NOAA/NESDIS/CoastWatch West Coast Node";
    String publisher_type "institution";
    String references "doi.org/10.25921/AE96-0E57";
    String sensor "Advanced Very High Resolution Radiometer (AVHRR)/3";
    String source "individual twice daily APP-x data";
    String sourceUrl "https://www.ncei.noaa.gov/metadata/geoportal/rest/metadata/item/gov.noaa.ncdc:C00941/html";
    String spatial_resolution "25 km";
    String standard_name_vocabulary "CF Standard Name Table (v26, 08 November 2013)";
    String summary "summary";
    String time_coverage_end "2018-12-31T14:00:00Z";
    String time_coverage_start "1982-01-01T04:00:00Z";
    String title "Sea Ice Thickness, Extended AVHRR Polar Pathfinder APP-X NCEI Climate Data Record V2, Arctic, 1982-Present, Twice 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.

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.


 
ERDDAP, Version 2.02
Disclaimers | Privacy Policy | Contact