Projet ICEPAC: Interactive Atlas on the Probability of Ice Hazard Affecting Marine and Coastal Infrastructure in the Context of Climate Change

Ice plays a crucial role in protecting shores and coastal infrastructure.

Given the current context of climate change, the gradual melting of shore fast ice is expected to leave coastal infrastructure and shores more exposed to large waves and storm surges, which, when combined, can pose significant risks to coastal infrastructure and the people using it. The ice hazard should be a factor considered in risk assessments in the planning, design, construction, maintenance, operation, and use of maritime transportation infrastructure in Canada.

Risk assessments should be able to determine the probability of the presence and duration as well as the spatial distribution of both land-fast and drift ice locally. Although some key sea ice parameters (e.g. average onset of freeze-up and thaw dates) are known from existing descriptive statistics, this information does not allow for a detailed characterization of sea ice evolution over time, but merely provides specific information.

Develop a probability model of the space-time variability of sea ice at the local scale based on data available in Nunavik.

• Study the space-time variability of sea ice at the regional level to determine the characteristics of the statistical distribution of ice concentrations for each 12.5 km area for every day of the year.

• Develop procedures to map ice concentrations at the local level (250 m) using satellite imagery.

• Study the space-time variability of sea ice at the local level (250 m) in proximity to marine and coastal infrastructure.

• Implement a decision-making tool in the form of an interactive online atlas of sea ice conditions.

• Study the impact of climate change on sea ice in relation to risk management for marine and coastal infrastructure

The analyses carried out under the IcePAC project provide a comprehensive perspective on the evolution of past, current and future sea ice conditions in the Hudson Bay sector.

This area located on the edge of the Arctic zone exhibits dynamic sea ice behaviours that can be difficult to define. Several tools were developed and implemented during the project in order to adequately study this complex dynamic:

The first, a probabilistic sea ice concentration model at a 12.5km resolution (IcePAC-R for “regional”) allows users to obtain the probability of a given sea ice concentration in a given location for each of the 52 weeks of the year.

The second tool is an automated mapping algorithm called IceMap250 that produces sea ice presence maps using MODIS Terra and Aqua satellite data at 250m resolution. A new ice cover map is produced on a daily basis and automatically made available on the IcePAC interface.

The third tool, the IcePAC-L (for “local”) model, estimates the probability of the presence of local ice at 250m resolution near communities located along the Hudson Bay coast for each of the 52 weeks of the year.

Finally, a fourth tool provides a future overview of sea ice dynamics through a frequency analysis of the data from two climate models (CanRCM4 and CCSM4).

A series of descriptive data (mean, standard deviation, etc.) and analytical data (cumulative freezing degree-days, empirically simulated ice thickness, simulated growth stage) are made available for the results of each of these tools as they are calculated.

The data are distributed through an online mapping interface, and are easily accessible and downloadable. This flexibility of use makes the IcePAC tool even more interesting for users.

Figure 1. ICEPAC Atlas interface.

• Ministère des Transports du Québec