SAR Composite Arctic Imagery (normalized radar cross section)

Updated: March 31, 2022

**NRT,NOAA Synthetic Aperture Radar Normalized Radar Cross Section Arctic Composite**
Service	Resource Locator
HTTPS	Portal Viewer Near Real-Time Search Directory: https://coastwatch.noaa.gov/data/pub0022/coastwatch/composite/nrcs/arctic/
THREDDS	https://coastwatch.noaa.gov/thredds/socd/coastwatch/catalog_composite_sar_nrcs_arctic_daily.html
ERDDAP	https://coastwatch.noaa.gov/erddap/search/index.html?page=1&itemsPerPage=1000&searchFor=noaacwSARnrcsnpoleDaily
FTP	Top Level: ftp ://ftpcoastwatch.noaa.gov/pub/pub0022/coastwatch/composite/nrcs/arctic/

[Please acknowledge "NOAA CoastWatch/OceanWatch" when you use data from our site.]

The daily composite of Synthetic Aperture Radar (SAR) Normalized Radar Cross Section (NRCS) imagery covering the Arctic and sub-Arctic maritime regions over a period of one day are available at 1-km resolution. These high-resolution, weather- and time-agnostic measurements of surface backscatter contain detailed information tailored for sea ice classification purposes.

A composite for typical day contains around 200-400 individual scenes gathered from several C-Band SAR systems, including Sentinel-1A/B, RADARSAT-2, and RADARSAT Constellation Mission, which are calibrated with values given by the SAR data provider and are then projected and resampled onto a 1km polar stereographic grid. The files are produced in SAROPS (SAR Operational Product System) by the Water Surface Conditions/Sea Surface Roughness group within the NOAA STAR Satellite Oceanography and Climatology Division.

For further details on the individual granules that make these composites and for links to the GeoTIFF versions of these files, please see the SAR NRCS page.

Data Courtesy of the Copernicus Program, RADARSAT Constellation Mission, and the Canadian Space Agency.

Key	Description
Platform/Sensor	Sentinel-1A/B / RADARSAT-2 / RADARSAT Constellation Mission / Synthetic Aperture Radar
Measurement/Products	NRCS Composites
Sample Filename	Source filenames begin with satellite, data source, year, month, day, hour, minute, second, Julian seconds, center latitude, center longitude, polarization, delimited with an underscore NRCS: S1A_ESA_2016_12_07_18_18_57_0534449937_178.66E_51.85N_VV_C5_GFS05 CDF_nrcs_level2.[png,nc] CoastWatch distributed composites: SAR_composite_2022070T0000_2022070T2359_NP06_1km_nrcs.[png,nc]
Dataset Type	Open
Processing Level	NRCS: Level-2, Averaged and resampled and mapped L-1 Composite: Level-4, Averaged and resampled and mapped L-1
Spatial Coverage	Arctic and sub-Arctic maritime regions (>40°N) Pixel width: 1.0669 km Pixel height: 1.0669 km Total width: 11018.7124 km Total height: 11018.7124 km Center: 89.9925 N, 90.0000 W Upper-left (pixel center): 23.6456 N, 90.0000 W Upper-right (pixel center): 23.6509 N, 0.0057 W Lower-left (pixel center): 23.6509 N, 179.9943 W Lower-right (pixel center): 23.6562 N, 90.0000 E
Temporal Coverage	00:00Z-23:59Z (daily)
Latency	Generated at 14Z the following day
Resolution	1km
Projection	Polar Stereographic / WGS84 projection:grid_mapping_name = "polar_stereographic" ; projection:latitude_of_projection_origin = 90. ; projection:straight_vertical_longitude_from_pole = -45. ; projection:standard_parallel = 60. ; projection:false_easting = 0. ; projection:false_northing = 0. ; projection:semi_major_axis = 6378137. ; projection:inverse_flattening = 298.257223563 ; projection:units = "m" ; projection:proj4 = "+proj=stere +lat_0=90 +lat_ts=60 +lon_0=-45 +k=1 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs" ; projection:spatial_ref = "PROJCS[\"unknown\",GEOGCS[\"unknown\",DATUM[\"WGS_1984\",SPHEROID[\"WGS 84\",6378137,298.257223563,AUTHORITY[\"EPSG\",\"7030\"]],AUTHORITY[\"EPSG\",\"6326\"]],PRIMEM[\"Greenwich\",0,AUTHORITY[\"EPSG\",\"8901\"]],UNIT[\"degree\",0.0174532925199433,AUTHORITY[\"EPSG\",\"9122\"]]],PROJECTION[\"Polar_Stereographic\"],PARAMETER[\"latitude_of_origin\",60],PARAMETER[\"central_meridian\",-45],PARAMETER[\"false_easting\",0],PARAMETER[\"false_northing\",0],UNIT[\"metre\",1,AUTHORITY[\"EPSG\",\"9001\"]],AXIS[\"Easting\",SOUTH],AXIS[\"Northing\",SOUTH]]" ;
Data Provider	Creator: NOAA STAR Release Place: Suitland, MD, USA Data courtesy of Copernicus Program, RADARSAT Constellation Mission, and the Canadian Space Agency
Formats	Portable Network Graphic (PNG) Network Common Data Format (NetCDF) with Climate-Forecast, ACDD, and CoastWatch attributes
Keywords	OAA, SAR, Sentinel-1, RADARSAT-2, RCM, arctic, polar, ice

Documentation:

Synthetic Aperture Radar Marine Users Manual. Ed C.R Jackson and J.R. Apel: NOAA: Washington, DC, USA, 2004. ISBN 0-16-073214-X