This data set is only available for a restricted user group, please contact us if you want to access these data.
Coverage, spatial and temporal resolution
Period and temporal resolution:
- 1998-11-01 to 2020-07-20
Coverage and spatial resolution:
- Northern Hemisphere
- Spatial resolution: 24 km x 24 km (1998-2020) and 4 km x 4 km (2004-2020); polar-stereographic grid, tangential plane at 60°N
- Geographic longitude: -180°E to 180°E
- Geographic latitude: 0°N to 90°N
- Dimension: 1024 rows x 1024 columns (24 km) and 6144 rows x 6144 columns (4 km)
- Altitude: following terrain
- NetCDF (Note: coordinates are stored in a separate netCDF file)
The data set does not include uncertainty estimates. However, this is a supervised, manual data set and it can be assumed that the analysis as well as the selection of the satellite data used has been handled carefully.
In situ observations are included into the IMS snow cover analysis, however, only with small weight because local effects (urban / airport heat island, different exposure to sun in mountain valleys) can easily result in an observed snow cover which is not representative for a larger area.
The IMS analysis can be regarded conservative. Usually, the IMS sea ice extent is smaller than the one given, e.g., by NIC sea ice charts or NSIDC sea ice concentration products based on passive microwave satellite data.
More information related to possible uncertainties is given on the IMS webpage and the two references given below.
ICDC / CEN / University of Hamburg
email: stefan.kern (at) uni-hamburg.de
NSIDC User Services
National Snow and Ice Data Center
email: nsidc (at) nsidc.org
IMS-website at NSIDC
Please cite usage of this data as follows:
National Ice Center. 2008, updated daily. IMS daily Northern Hemisphere snow and ice analysis at 1 km, 4 km, and 24 km resolutions. Boulder, CO: National Snow and Ice Data Center. Digital media [last access date: July 21, 2020], provided in netCDF format by ICDC (http://icdc.cen.uni-hamburg.de).