0 0 No sea ice
1 1 Slush or pancake ice
2 2 Level ice
3 3 Rafted ice
4 4 Pressure ridge/ridged ice
5 5 Hummocks
6 6 Pressure ice
7 7 Rotten disintegrated ice
8 8 Not used
9 9 Not determined or unknown
15 15 Missing value
