Ice Information in the Arctic

(from AMSA Report 2009)

Without sea ice, the needs for environmental information in the Arctic would be little different from the world’s other oceans - wind and weather, waves, tides, currents, etc. Sea ice is what sets the Arctic apart - what makes navigation in the Arctic especially unique and hazardous.

Sea ice in the Arctic has an annual cycle of freeze and melting that will not change in the future. When the sun goes down in the autumn and the extreme cold arrives, the ocean freezes. March is the month of maximum ice coverage. Through the summer months, the ice melts and retreats to a minimum extent in September.

It is generally agreed that the reduction in the thickness and extent of Arctic sea ice will continue into the future until, eventually, the Arctic will become free of sea ice in summer - much like the Baltic Sea, Sea of Okhotsk or the waters off the east coast of Canada. However, this will not eliminate the hazard that ice presents to Arctic shipping. There will still be a winter ice cover and significant inter-annual variability means that not all of the ice will melt every year, so scattered old ice floes will hide in the pack ice along with icebergs and ice island fragments. Moving ice driven by winds and currents will create a dynamic and hazardous operating environment. Variability in the onset of autumn freeze-up will present the risk of getting trapped in the Arctic over winter. Spring break-up to mark the start of summer navigation will vary and, as happens now in more southerly seas, shippers eager to start work will test the limits of their vessels in ice.

As more ships venture into the Arctic, the demand for ice information, as well as other ocean data, products and services, will continue to increase and the resources available to meet this increased demand will be stretched. The ice parameters needed in the future will not change significantly but will be required over larger geographic areas and longer periods of the year. Operators will still need to know where the ice is and isn’t; where it’s going to be, how closely packed it is and how thick and strong it is; generally, how difficult it will be to go around or, when necessary, go through. These parameters will be needed on a variety of space and time scales - from the hemispheric to the local, from months and weeks to daily or even hourly - to support tactical and strategic route planning for ships, scientific study and the development of policy and regulations to ensure safe marine practices.

The needs of mariners for ice information are currently met by a number of organizations, including national ice services that produce information for the Arctic that is generally freely available as a public service funded by tax-payers; academic institutions that provide ice information as part of an ongoing research program or to support field research campaigns; and commercial ice information services that provide services that are specific to individual clients with particular needs. As more ships venture into the Arctic and the demand for ice information and related services increases, there will be increasing pressure on the resources of ice information providers.

The national ice services collaborate in the Joint WMO-IOC Technical Commission for Oceanography and Marine Meteorology Expert Team on Sea Ice, the body that establishes and maintains the standards for ice information internationally; and in the International Ice Charting Working Group (IICWG), an ad hoc group that coordinates ice information services internationally and advises the Expert Team on Sea Ice. As a result of this collaboration, there is an internationally accepted nomenclature for ice in the ocean, common charting and coding practices and cooperative information sharing among the ice services.

Ice information products include ice charts depicting the distribution and characteristics of the sea ice in an area; satellite images of ice-infested waters, often with interpretative text added; and text messages describing ice conditions. There is a wide range of scales for these products – from hemispheric charts that are useful for long-range planning to the navigation scale to support tactical vessel movements.

It is certain that the needs for ice information will evolve as more Arctic shipping develops. It is impossible to predict exactly how that evolution will occur because it depends on many factors - how the ice distribution itself changes, where resources are found, what markets are developed, advances in ship design and improving technology to observe, produce and disseminate ice information. The following examples are intended to provide illustrations of the particular ice information needs for some probable scenarios.

Potential shipping routes for extracting resources – principally oil, gas and minerals - will primarily be along shortest distance lines from the production sites to markets. It is likely the vessels used in this trade will be purpose-built for the trade in question and will operate year-round. They will be ice-strengthened and powered sufficiently to handle the most severe ice conditions encountered along the route. Ice information of most importance to these vessels will be that which can help them reduce time and fuel consumption en route as well as minimize the risks and delays that can be caused by difficult ice conditions around loading docks and piers.

Arctic transit shipping, using the Arctic Ocean as a short cut between Atlantic and Pacific, is not expected to become common because of the seasonal nature of the ice cover. Vessels designed to reliably pass through the winter Arctic ice cover will be greatly disadvantaged economically during the ice-free season. If transit shipping does occur in the Arctic, it will likely be limited to the summer season. These vessels will have some ice-strengthening to handle summer Arctic ice encounters but will not be able to deal with winter conditions. The most important ice information for this trade will be medium- and long-range forecasts of break-up and freeze-up to help companies decide when to head for the Arctic and when to get out in order to avoid being trapped over a winter. Close in the order of importance will be analyses and short-range forecasts of ice concentration, strength and motion to allow masters en route to set courses that avoid ice as much as possible.

Arctic Council, 2009, Arctic Marine Shipping Assessment (AMSA), Arctic Council.©