Table AIV-20.—WMO CODE 0739
WMO CODE 0739
Di - True bearing of principal ice edge.
Code 0 - Ship inshore or in flaw lead.
Code 7
Toward NW
Code 6 - Toward W
Code 5
Toward SW
Code 8
Code 1
Toward N
Toward NE
Toward E - Code 2
Code 4
Code 3
Toward S
Toward SE
Code 9 - Not determined (ship in ice).
Code / - Unable to report or only ice of land origin present.
Table AIV-21.—WMO CODE 3739
WMO CODE 3739
Si - Stage of (sea ice) developement.
Code
Sea ice observed
0
1
2
3
4
5
6
7
8
9
/
New ice only (frazil, grease, slush, shuga).
Nilas or ice rind, less than 10 cm thick.
Young ice (grey, grey-white), 10 to 30 cm thick.
Mostly new and/or young ice with some first-year ice.
Mostly thin first-year ice with some new or young ice.
All thin first-year ice, 30 to 70 cm thick.
Mostly medium first-year ice (70 to 120 cm thick) and thick
first-year ice (120 cm thick), with some thinner first-year ice.
All medium and thick first-year ice.
Mostly medium and thick first-year ice, with some old ice (usually
more than 2 meters thick.
Mostly old ice.
Unable to report: Low visibility, darkness, only ice of land
origin present, or ship is more than 0.5 nm from ice edge.
Table AIV-22.—WMO CODE 0264
WMO CODE 0264
a3 - Standard isobaric surface for which
the geopotential height is reported
Code
Level
1
1000 hPa
2
925 hPa
5
500 hPa
7
700 hPa
8
850 hPa
AIV-20
