Ice decay and the ice regime system

• Main Authors: Timco, G. W., Johnston, M., Kubat, I.
• Format: Report
• Language: English
• Published: 2001
• Subjects: Arctic; Rotten; Sea ice
• Online Access: https://doi.org/10.4224/12340994; https://nrc-publications.canada.ca/eng/view/ft/?id=5081890e-146a-4a9f-a82c-2c70019b0329; https://nrc-publications.canada.ca/eng/view/object/?id=5081890e-146a-4a9f-a82c-2c70019b0329; https://nrc-publications.canada.ca/fra/voir/objet/?id=5081890e-146a-4a9f-a82c-2c70019b0329

The Canadian Ice Regime System takes into account the decay of sea ice by allowing the addition of +1 to the Ice Multiplier for ice that is deemed to be decayed at the "rotten" stage. This report examines this approach based on an analysis of the strength of both first-year sea ice and multi-year sea ice, and the damage statistics for Arctic vessels. The analysis shows that there is no quantitative scientific basis for the current approach of taking into account the decay of sea ice in the Ice Regime System. The report provides a detailed discussion of the analysis with recommendations that (1) the decay of sea ice should be recast in terms of the strength of ice; (2) the summer bonus for reduced ice strength should be given once the ambient air temperature has been above 0°C for one month; (3) an analysis should be performed to define a similar criterion to be used during the growth (autumn) season; and (4) there should be no bonus for decayed multi-year ice. NRC publication: Yes