Ice Chart Colour Codes

International Ice Chart Working Group, October 2000

John Falkingham, Canadian Ice Service

WMO Hatching Codes

Total Concentration

WMO Hatching Codes

Stage of developmentand thickness

CIS Manice Colour CodeHatching = total concentrationColour = predominant ice type

MANICE Colour Code

Canadian Ice Service Colour Code

• Primarily intended for marine navigation use– multi-year ice emphasized– thin ice forms not prominent

• Green-yellow-red colouring based on Total Concentration except:– Ice less than 15 cm thick is not considered in

Total Concentration

Open or Bergy Water

Blue = open or bergy water

Ice types Thicker than 15 Cm

Green = 1 to 3 tenths of ice thicker than 15 cm

Yellow = 4 to 6 tenths of ice thicker than 15 cm

Orange = 7 to 8 tenths of ice thicker than 15 cm

Red = 9 to 10 tenths of ice thicker than 15 cm

Canadian Ice Service Colour Code

Old Ice .

Purple Dash Lines indicate presence of 1 to 4 tenths old ice

Solid Purple indicates presence of more than 4 tenths old ice

Thin Ice

Blue stars indicate predominance of ice thinner than 10 cm

Red stars indicate predominance of ice 10-15 cm

Fast Ice

Black regardless of thickness

Canadian Ice ServiceColour Code

1 to 4/10

5 to 10/10

open or bergy water (less than 1/10)

1 to 3/10

Ice Thicker Than 15 cm

4 to 6/10

7 to 8/10

9 to 10/10

fast ice

less than 10 cm (new ice)

10 to 15 cm (grey ice)

Predominant Ice - 15 cm or less

Old Ice

Ice coverage in tenths

Colour Code Observations• Stars or other symbols scattered across a chart

tend to clutter the display - problem for ECDIS• “Green” may not be appropriate for any

amount/type of ice– falsely indicates a “go” condition?

• One colour code will not suit all users– let users choose their own colour scheme tailored to

their needs?

– but have “default” international standard

• International standard colour code should be very simple and intuitive

Tentative Proposal

Open water / Bergy water

1-3 tenths ice

4-6 tenths ice

7-8 tenths ice

9-10 tenths ice

Fast Ice any thickness

ignore thin ice (<15 cm)

National practice to superimpose symbols (e.g. stars, bars) to delineate significant ice features (e.g. multi year ice)

Any concentration of thin ice (<15 cm)