Notation	Name	Description	Status
0	New ice only (frazil ice, grease ice, slush, shuga)		stable
1	Nilas or ice rind, less than 10 cm thick		stable
2	Young ice (grey ice, grey-white ice), 10-30 cm thick		stable
3	Predominantly new and/or young ice with some first-year ice		stable
4	Predominantly thin first-year ice with some new and/or young ice		stable
5	All thin first-year ice (30-70 cm thick)		stable
6	Predominantly medium first-year ice (70-120 cm thick) and thick first-year ice (>120 cm thick) with some thinner (younger) first-year ice		stable
7	All medium and thick first-year ice		stable
8	Predominantly medium and thick first-year ice with some old ice (usually more than 2 metres thick)		stable
9	Predominantly old ice		stable
30	Unable to report, because of darkness, lack of visibility or because only ice of land origin is visible or because ship is more than 0.5 nautical mile away from ice edge		stable
31	Missing value		stable