Waves – a hidden factor influencing Arctic ice retreat?

The first detailed research on the impact of waves on Arctic sea ice will allow scientists to determine the areas more vulnerable to climate change.

Research published in the Proceedings of the Royal Society A, concluded that as waves break up the ice it melts more easily. As yet, no climate models include the impact of waves on sea ice which implies that the extent and speed of Antarctic and Arctic sea ice retreat have not been estimated correctly.

The study also found that when larger areas of ocean surface are exposed so wave generation by wind is increased. It has also been found that higher albedo (a measure of the reflectivity of the earth's surface), a result of the larger sea ice cover, keeps the ocean temperatures low. However, ice melt reveals the dark ocean causing albedo decrease, therefore leading to an increase of the temperature of the ocean.

The study, undertaken by Dr Luke Bennetts Research Fellow in the School of Mathematical Sciences at the University of Adelaide, investigated the regular water-wave transmission by placing arrays of floating disks in a wave basin and measuring the wave energy. Dr Bennetts said: “Wave energy is scattered by ice floes and is transferred into collisions between ice floes and into waves running over the tops of the floes, both of which impact the ice cover”.

This wave-ice activity appears over hundreds of kilometres into the ice-covered ocean. Therefore models predicting penetration of wave distances need to be developed in order to establish regions of possible breakage. This will result in a better understanding of regional variability in the sea ice.

Paper:

http://www.maths.adelaide.edu.au/luke.bennetts/My_Preprints/PRSA14_pre.pdf