Extreme weather events in the Arctic will become more common as the winter ice cover retreats, with potentially severe consequences for human activity, says the Sweden-based Bjerknes Centre for Climate Research (BCCR).
One of the most visible signs of climate change is the dramatically reduced ice cover in the Arctic. The retreat of the sea ice leads to rapid changes in the weather conditions in these areas. Regions that have been covered by sea ice until now will be exposed to new kinds of severe weather. This may have dire consequences for human activities in the Northern regions.
Increased Activity and More Extreme Weather
Large increases in the potential for extreme weather events were found along the entire southern rim of the Arctic Ocean, including the Barents, Bering and Beaufort Seas. While these areas are sparsely populated, an increasing commercial marine activity is predicted there because the sea ice is set to retreat.
One consequence of climate change is that new areas are uncovered, opening for commercial activities. At the same time, commercial activities in the North (e.g. fisheries, oil industry and shipping) will become increasingly vulnerable to extreme weather as the activities in these areas increase.
In adddition, the limited existing infrastructure for responding to maritime accidents in the Arctic must be strengthened. As Arctic sea ice declines and commercial activities in the region increases, this becomes incresingly important.
Cold Air Is the “Fuelâ€
Arctic weather has many faces. While the conditions over the Arctic Ocean ice sheet are frequently calm and cloudy, the warm regions with open ocean surrounding it are host to severe weather, such as explosive mid-latitude storms, polar lows and arctic fronts.
A common feature of these weather types is that they form when cold air masses wander out from over the ice sheets over the warm ocean to be heated from below. In the North Atlantic, such conditions arise frequently along the Gulf Stream and its northern branches. The North-East Atlantic (the Greenland, Iceland, Norwegian and Barents Seas) is particularly prone to marine cold-air outbreaks (MCAOs).
Some Good News
As the sea ice in the Northern Hemisphere retreats rapidly, the regions with the highest frequency of MCAOs today are pulled towards the north. Thus, a projected decrease in the strength of MCAOs along the most densely populated coastlines was also found. This may prove to be good news for people along the coastlines of Norway, Iceland, the British Isles and Northern Europe in general.
BCCR is a joint venture between University of Bergen, Institute of Marine Research, and Nansen Environmental and Remote Sensing Center.
(Photo Courtesy of NOAA)
