The National Snow and Ice Data Center was informed on 24 June 2025 that the Department of Defense (DoD) will cease processing and delivering the Special Sensor Microwave Imager/Sounder (SSMIS) data no later than 30 June 2025.
Affected Data Products:
The SSMIS data serve as input for the following NOAA@NSIDC data sets, which will therefore stop processing after 30 June 2025:
- Near-Real-Time NOAA/NSIDC Climate Data Record of Passive Microwave Sea Ice Concentration
- Sea Ice Index
What This Means For You:
As a user of these datasets, you should anticipate a gap in data availability during the transition to alternative sources.
Our Response:
We are actively evaluating possible alternative data sources, including AMSR2, to minimize disruption to your research and operations. We will communicate updates as soon as they become available.
AMSR2 Sea Ice Concentration Alternative:
In the interim, we recommend exploring the AMSR2 portion of the Near-Real-Time NOAA/NSIDC Climate Data Record of Passive Microwave Sea Ice Concentration. As documented in NSIDC Special Report #27, the AMSR2 data are prototype and not yet fully intercalibrated with older data. Users will notice differences in sea ice extents since AMSR2’s higher resolution provides better ice edge detection than SSMIS. These data may serve as a temporary alternative while we develop a fully intercalibrated version of AMSR2.
Sea Ice Extent Values Alternative:
If you need sea ice extent numbers for the Northern Hemisphere, another NSIDC data set called MASIE may provide you with the data you need.
We are committed to supporting you through this transition. Please reach out to nsidc@nsidc.org with any questions or concerns.