National Snow and Ice Data Center DAAC (NSIDC DAAC)
The NSIDC DAAC provides data and information for snow and ice processes, particularly interactions among snow, ice, atmosphere, and ocean, in support of research in global change detection and model validation. NSIDC also provides general data and information services to the cryospheric and polar processes research community.
Available Data
Terra and Aqua Products
- Snow and Sea Ice Extent from MODIS on Terra and Aqua
(Resolution: Snow cover at 500 m and 0.5 deg; sea ice extent at 1 km and 4 km | Availability: Terra, February 2000 to present; Aqua, July 2002 to present | Coverage: Global)NSIDC's holdings include several Moderate Resolution Imaging Spectroradiometer (MODIS) snow and sea ice extent products. These products consist of Level 2 swath data and Level 3 gridded composites.
- Advanced Microwave Scanning Radiometer-EOS (AMSR-E) on Aqua
(Resolution: 5 to 56 km | Availability: May 2002 to present | Coverage: Global)AMSR-E data include brightness temperatures, soil moisture, ocean products (water vapor, cloud liquid water, sea surface temperature), rain, snow, and sea ice in both swath and gridded formats.
Photo: Sea ice conditions for September 2002, 2003, and 2004, derived
from the Sea Ice Index. Ice concentration anomaly images (the difference in
estimated concentration from the mean) and the 1979-2000 median September ice
edge (indicated by the pink line) are combined in each panel. For each year, the
ice edge is well north of its median position off the coasts of Alaska and
Siberia. There is a striking lack of sea ice off the east coast of Greenland, a
feature noted for the first time in 2002. Anomalies are not calculated north of
the circle centered over the pole (shown as light green) where satellites prior
to 1988 provided no coverage.
Validation Data
- AMSR-E Validation Data
(Resolution: Variable | Availability: 2002 to 2005 | Coverage: Iowa, Oklahoma, Georgia, Alabama, Arizona, Mexico, and Brazil)The AMSR-E validation effort addresses data quality through comprehensive calibration and validation programs. These programs characterize the accuracy and precision of AMSR-E observations and their derived products, and provide for the assessment and refinement of algorithm performance for the standard AMSR-E products.
- Cold Land Processess Experiment
(Resolution: Variable | Availability: 2002 and 2003 | Coverage: Northern Colorado and Southern Wyoming)The Cold Land Processes Experiment (CLPX) is a multi-sensor, multi-scale field program designed to extend the current local-scale understanding of water fluxes, storage, and transformations to regional and global scale. Using ground, airborne, and spaceborne observations, the experiment emphasizes the development of a strong synergism between processoriented understanding, land surface models, and microwave remote sensing.
Passive Microwave Products
- Nimbus-7 SMMR and DMSP SMM/I
(Resolution: 25 km | Availability: SMMR, 1978 to 1987; SSM/I, 1987 to present | Coverage: Polar regions)Scanning Multichannel Microwave Radiometer (SMMR) and Special Sensor Microwave/Imager (SMM/I) data include gridded brightness temperatures and sea ice type, extent, and concentration.
- Near-Real-Time SSM/I EASE-Grid Daily Global Ice Concentration and Snow Extent
(Resolution: 25 km | Availability: January 2000 to present | Coverage: Polar regions)Near-real-time maps are meant to provide a best estimate of current ice and snow conditions, based on information and algorithms available at the time the data were acquired.
- Northern Hemisphere EASE-Grid Weekly Snow Cover and Sea Ice Extent, Version 2
(Resolution: 25 km | Availability: 1966 to 2001 and 1978 to 2001 | Coverage: Northern Hemisphere)This data set combines snow cover and sea ice extent at weekly intervals for 1978 to June 2001, and snow cover alone for 1966 to June 2001.
NSIDC distributes a host of ancillary sea ice products, including ice
extent, melt onset data, climatologies, ice persistence, total
ice-covered area, and ocean masks.
AVHRR Products
- AVHRR 1-km Level 1b Polar Data Set
(Resolution: 1.1 km at nadir | Availability: 1992 to present | Coverage: Polar regions)This Advanced Very High Resolution Radiometer (AVHRR) data set provides nearly complete coverage of sea ice, land ice, and land in polar regions at 1.1-kilometer resolution for all five bands of the AVHRR sensor.
- AVHRR Polar Pathfinder Twice-Daily EASE-Grid Composites
(Resolution: 1.25, 5, and 25 km | Availability: 1992-1998 (1.25 km), 1981-1998 (5 km), 1981-2000 (25 km) | Coverage: Polar regions)These data sets are a collection of products for both poles, consisting of twice-daily gridded and calibrated satellite channel data and derived parameters. The parameters include average albedo and skin temperature, solar zenith angle, surface type mask, cloud mask, cloud fraction files, and others. Data are in 1-byte and 2-byte integer gridded format.
Altimetry and Elevation Data
- Ice, Cloud, and Land Elevation Satellite (ICESat) Geoscience Laser Altimeter System (GLAS)
(Resolution: 60-m spot size at nadir | Availability: Begins Feb. 2003; see release schedule for availability | Coverage: Global, from 86° N to 86° S latitude)The main objective of the ICESat mission is to measure ice sheet elevations and changes in elevation through time. Secondary objectives include measurements of cloud and aerosol height profiles, land elevation, vegetation cover, and sea ice thickness.
- RAMP Digital Elevation Model (DEM) Version 2
(Resolution: 200 m, 400 m, and 1 km | Availability: Collected between 1940s and 2000 | Coverage: Antarctica, from 60° S to 90° S latitude)This high-resolution RADARSAT Antarctic Mapping Project (RAMP) DEM combines topographic data from a variety of sources to provide consistent coverage of all of Antarctica.
- Greenland 5 km DEM, Ice Thickness, and Bedrock Elevation Grids
(Resolution: 5 km interpolated, but true horizontal resolution varies according to slope and surface characteristics | Availability: Collected between 1970s and 1990s | Coverage: GreenlandA Digital Elevation Model (DEM), ice thickness grid, and bedrock elevation grid of Greenland are available in ASCII text format at a 5 km grid spacing in a polar steriographic projection.
Polar Atmospheric Data
- Historical Arctic and Antarctic Observational Data
(Availability: Varies by station, 1913 to 2002 | Coverage: Arctic and Antarctic)This product consist of meteorological data from 105 Arctic weather stations and 137 Antarctic stations. Variables include wind direction, wind speed, visibility, air temperature, dew point temperature, and sea level pressure. Temporal coverage varies by station, with the earliest record in 1913 and the latest in 2002.
Additional Products
The NSIDC DAAC and its host, the collocated National Snow and Ice Data Center, distribute data sets and products acquired outside EOSDIS. Data subjects include permafrost, frozen ground, glaciers, ice shelves, icebergs, ice sheets, snow cover, ice velocity, and ocean chemistry and temperature.
Data Tools
NSIDC distributes a variety of data manipulation tools for specific data
types. It also has tools for searching, ordering, and subsetting gridded
data.
Data Access
Data orders may be placed at the NSIDC DAAC through the EDG data search-and-order system. Users may also access information about NSIDC data holdings through the online data catalog on NSIDC's Web site. Depending on the data set, NSIDC data products are available on a variety of media, including FTP, CD-ROM, 8-mm tape, DVD, and DLT.
For assistance or additional information, contact:
NSIDC DAAC User Services
National Snow and Ice Data Center
University of Colorado
Phone: +1 303-492-6199
Fax: +1 303-492-2468
E-mail: nsidc@eos.nasa.gov or nsidc@nsidc.org