ICE - Ice group indicator
ci - Concentration or arrangement of sea ice
Code Description
0 No ice.
1 Ship in open lead more than 1 nm wide or ship in fast ice with boundary beyond limit
of visibility.
2 -5 Ice concentration uniform.
2 Open water or very open pack ice,<3/10 concentration.*
3 Open pack ice 4/10 to <6/10 concentration.*
4 Close pack ice 7/10 to <8/10 concentration.*
5 Very close pack ice 9/10 or more, but not 10/10 concentration.*
6 -9 Ice concentration not uniform.
6 Strips and patches of pack ice with open water between.*
7 Strips and patches of close or very close pack ice with areas of lesser concentration
between.*
8 Fast ice with open water,very open or open pack ice to seaward of the ice boundary.*
9 Fast ice with close or very close pack ice to seaward of the ice boundary.*
/ Unable to report,because of darkness,poor visibility or because ship is more than 0.5 nm away from ice edge.
(* Ship in ice or within 0.5 nm of ice)
Si - Stage of development
Code Description
0 New ice only (frazil ice,grease ice,slush,shuga).
1 Nilas or ice rind,<10 cm thick.
2 Young ice (grey ice,grey-white ice) 10 -30 cm thick.
3 Predominantly new and/or young ice with some first-year ice.
4 Predominantly thin first-year ice with some new and/or young ice.
5 All thin first-year ice (30 -70 cm thick).
6 Predominantly medium first-year ice (70 -120 cm thick) and thick first-year ice (>120
cm thick) and some thinner (younger) first-year ice.
7 All medium and thick first-year ice.
8 Predominantly medium and thick first-year ice with some old ice (usually more than 2
metres thick).
9 Predominantly old ice.
/ Unable to report,because of darkness,poor visibility or only ice of land origin visible or
ship is more than 0.5 nm away from ice edge.
bi - Ice of land origin
Code Description
0 No ice of land origin.
1 1-5 icebergs,no growlers or bergy bits.
2 6-10 icebergs,no growlers or bergy bits.
3 11-20 icebergs,no growlers or bergy bits.
4 Up to and including 10 growlers and bergy bits no icebergs.
5 More than 10 growlers and bergy bits no icebergs.
6 1-5 icebergs with growlers and bergy bits.
7 6-10 icebergs with growlers and bergy bits.
8 11-20 icebergs with growlers and bergy bits.
9 More than 20 icebergs with growlers and bergy bits a major hazard to navigation.
/ Unable to report because of darkness,poor visibility or only sea ice is visible.
Di - Bearing of principal ice edge
Code Description
0 Ship in shore or flaw lead.
1 Ice edge towards NE.
2 Ice edge towards East.
3 Ice edge towards SE.
4 Ice edge towards South.
5 Ice edge towards SW.
6 Ice edge towards West.
7 Ice edge towards NW.
8 Ice edge towards North.
9 Not determined (ship in ice).
/ Unable to report,because of darkness,poor visibility or only ice of land origin visible.
zi - Ice situation and trend over preceding three hours
Code Description
0 Ship in open water with floating ice in sight.
1 Ship in easily penetrable ice;conditions improving.**
2 Ship in easily penetrable ice;conditions not changing.**
3 Ship in easily penetrable ice;conditions worsening.**
4 Ship in ice difficult to penetrate;conditions improving.**
5 Ship in ice difficult to penetrate;conditions not changing.**
6-9 Ice difficult to penetrate,conditions worsening.
6 Ice forming and floes freezing together.**
7 Ice under slight pressure.**
8 Ice under moderate or severe pressure.**
9 Ship beset.**
/ Unable to report,because of darkness or poor visibility.
(** Ship in ice)