Notation	Name	Description	Status
0	Ship in open water with floating ice in sight		stable
1	Ship in easily penetrable ice; conditions improving		stable
2	Ship in easily penetrable ice; conditions not changing		stable
3	Ship in easily penetrable ice; conditions worsening		stable
4	Ship in ice difficult to penetrate; conditions improving		stable
5	Ship in ice difficult to penetrate; conditions not changing		stable
6	Ship in ice difficult to penetrate and conditions worsening. Ice forming and floes freezing together		stable
7	Ship in ice difficult to penetrate and conditions worsening. Ice under slight pressure		stable
8	Ship in ice difficult to penetrate and conditions worsening. Ice under moderate or severe pressure		stable
9	Ship in ice difficult to penetrate and conditions worsening. Ship beset		stable
30	Unable to report, because of darkness or lack of visibility		stable
31	Missing value		stable