Seasonality of Operations and Sea Ice Extent

(from AMSA Report 2009)


The Arctic is defined by extreme seasonal vaibility , impacting the behavior of the animals that live in and migrate to and from the region, as well as human activity. Generally, most of the central Arctic is ice-covered, dark and very cold throughout the winter months. There are some areas, such as the Aleutian Island chain, the northern coast of Norway, southern Iceland and the Murmansk region in northern Russia where, due to ocean currents and other factors, ice does not form in the Arctic in the winter. However, these areas still experience darkness, extreme cold and variable conditions. The Arctic summer is the opposite extreme, with 24 hours of light and temperatures that can be uncomfortably warm. The pattern of vessel traffic in the AMSA database shows that vessel activity in the Arctic is highly affected by seasonal ability .

The AMSA GIS database includes Arctic sea ice maps for each month in 2004, with information collected and compiled by national ice administrations working cooperatively to create an Arctic sea ice picture. When layered with 2004 seasonal vessel traffic this data demonstrates how vessel traffic patterns interacted with the minimum sea ice extent at the time.

Maps 5.5 and 5.6 show the differences in sea ice extent between winter (January) and summer (July) traffic levels. Map 5.5 shows virtually no vessel activity in the central Arctic in the winter, although some takes place on the fringes in year-round ice-free zones. As mentioned earlier, the database indicates that only year-round commercial operations in the Arctic in seasonally ice-covered areas were into Dudinka in the Russian Federation and Deception Bay in Canada. These two operations were the only commercial icebreaking activities taking place in 2004; government icebreakers and research vessels conducted all other icebreaking that year. The data indicates that this was done only in the spring, summer and fall seasons.

Map 5.5 January traffic and Map 5.6 July traffic 

Source: AMSA

Map 5.6 demonstrates the surge in vessel activity in the summer season, when all of the community re-supply takes place and most bulk commodities are shipped out and supplies brought in for commercial operations. Summer is also the season when all of the passenger and cruise vessels travel to the region. Wildlife in the Arctic also follows this pattern: although most species migrate earlier in the spring before ice break-up, animals gather in large aggregations in the summer to feed and reproduce. This is important to consider when examining potential environmental and ecosystem impacts that may result from current or increased vessel activity in the region.

Summer and fall are the safest and most economical seasons for marine activity; therefore, activities such as resource development, tourism or community re-supply will most likely increase in the summer months. There may be a few exceptions, where high value commodities may drive year-round operations, but that will be driven by economics, not climate. If ice conditions continue to change and sea-ice extent reduces as predicted in the near term, the summer and fall shipping seasons will most likely lengthen. Even as perennial sea ice is reduced, winter in the central Arctic will remain inhospitable to marine navigation; therefore, future Arctic vessel activity will continue to be highly seasonal in the region.


    Arctic Council, 2009, Arctic Marine Shipping Assessment Report, Arctic Council.©