Daily sea ice thickness in the Northern Hemisphere

Daily Northern Hemisphere Sea Ice Thickness Dataset Derived from Satellite-Based Sea Ice Thermodynamic History This dataset provides daily sea ice thickness estimates for the Northern Hemisphere from January 2007 to December 2025. The sea ice thickness was derived from the thermodynamic growth history of sea ice, reconstructed from passive microwave satellite observations obtained by the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) and the Advanced Microwave Scanning Radiometer 2 (AMSR2). The methodology is described in:Kimura, N. and Hasumi, H. (2026): Estimating Arctic sea ice thickness from satellite-based ice history. The Cryosphere, 20, 2331–2349. https://doi.org/10.5194/tc-20-2331-2026 Temporal Coverage 2007-01-01 to 2011-09-27 2016-07-16 to 2025-12-31 Total: 5,187 daily fields. The gap between 2011 and 2016 corresponds to the interval between the AMSR-E and AMSR2 missions. Dataset Contents The dataset is distributed in two formats. ----- 1. Gridded Sea Ice Thickness Data (Binary Format) Daily sea ice thickness fields on a polar stereographic grid. File naming Compressed files: sitYYYYgrid.zip where YYYY indicates the year. After extraction: sitYYMMDDnh_grid.dat where YY is the year, MM the month, and DD the day. Variable Sea ice thickness (m) Data format Headerless binary file 4-byte floating-point values Grid size: 900 × 900 cells Grid information Polar stereographic projection Nominal grid spacing: 10 km Grid dimensions: 900 × 900 Latitude and longitude for all grid cells are provided in: latlon900.txt Each line contains: x-index, y-index, latitude (°N), longitude (°E) for all 810,000 grid cells. Data values Sea ice thickness is expressed in meters. Grid cells without sea ice are assigned a value of 0.0. Missing values within the sea ice cover are generally not present. ----- 2. Point-Based Sea Ice Thickness Data (Text Format) Daily sea ice thickness data stored as geographic coordinates and thickness values. File naming Compressed files: sitYYYY.zip where YYYY indicates the year. After extraction: sitYYMMDDnh.txt where YY is the year, MM the month, and DD the day. Data format Plain text file. Each line contains: latitude (°N), longitude (°E), sea ice thickness (m) Only grid cells containing sea ice are included. Therefore, the number of records varies seasonally, with more records during winter and fewer during summer. The data points correspond to the same 10-km polar stereographic grid used in the gridded dataset. ----- Notes The dataset covers sea ice over the entire Northern Hemisphere. Sea ice thickness is estimated from satellite-derived thermodynamic ice-growth history and is not a direct observational product. The gridded and point-based datasets contain identical thickness information in different formats for user convenience. Recommended Citation Users of this dataset are requested to cite the following publication describing the methodology used to derive the sea ice thickness estimates: Kimura, N. and Hasumi, H. (2026): Estimating Arctic sea ice thickness from satellite-based ice history. The Cryosphere, 20, 2331–2349. https://doi.org/10.5194/tc-20-2331-2026