- The NISE snow and sea ice algorithm both use near-real-time brightness temperature observations from the SSMIS instrument on DMSP-F18.
- The coefficients for the NISE snow algorithm were updated to better match results from DMSP-F13 as a result of an inter-calibration between F13 and F17 during an overlap period from 3/27/2008-3/26/2009 and between F17 and F18 during an overlap period from 7/1/2014-6/30/2015.
- ESDT metadata was updated to reflect the change in data set version number.
The NISE Version 5 data record begins 12/01/2016.
- Near-real-time combined sea ice and snow product (Armstrong and Brodzik, 2001; Maslanik and Stroeve, 1999)
- Useful for large-scale monitoring of sea ice and snow conditions (Armstrong and Brodzik, 2001; Maslanik and Stroeve, 1999)
- Uses data from up to 5 days previous to fill in all spatial gaps (particularly important for lower latitude snow cover) (Armstrong and Brodzik, 2001)
- Microwave observations provide surface snow and ice coverage during cloudy and night-time (including polar night) conditions (Cavalieri et al., 1999)
- Good source as input to products/models requiring a spatially complete snow and sea ice cover field at moderate/low resolution (Armstrong and Brodzik, 2001)
- Low spatial resolution (25 km gridded) limits detail on concentration and precision of sea ice edge; is unsuitable for operational/navigational support (Cavalieri et al., 1999) and/or for detailed mapping of snow extent (Armstrong and Brodzik, 2002)
- Underestimates sea ice concentration during melt season (Kern et al., 2020) and/or when the ice is thin (Ivanova et al., 2015)
- Underestimates thin snow (Armstrong and Brodzik, 2002)
- Snow in dense forest and mountainous regions may be missed or underestimated (Armstrong and Brodzik, 2002)
- Wet snow is not accurately retrieved (Armstrong and Brodzik, 2002)
- There is a gap in coverage near the coast due to low spatial resolution and mixed land-ocean footprints (Armstrong and Brodzik, 2002)
- Near-real-time product with no planned reprocessing for long-term consistency; should not be used to derive long-term trends in sea ice or snow (Cavalieri et al., 1999)