On Monday, 11 July from 3:00 p.m. through Wednesday, 13 July until 5:00 p.m. (USA Mountain Time), NSIDC data distribution, services, and Web site will be unavailable to accommodate a major upgrade to our data center. We apologize for any inconvenience this may cause you. Need to talk to us? You can always contact our friendly User Services Office at firstname.lastname@example.org or + 1 303.492.6199.
Long-term snow cover frequencies (1966-2003) derived from Northern Hemisphere EASE-Grid Weekly Snow Cover and Sea Ice Extent Version 3 data, used for Processing Steps, Step 4. Southern Hemisphere permanent ice mask, derived from BU-MODIS land cover data.