Waves in the Arctic Ocean 1992-2014

In the past decade the Arctic Ocean has experienced increasing losses of sea ice which has a direct impact on the wave field. The sea state of the Arctic is largely dependent on the ice-free area and wind. This study characterizes the waves in the Arctic using detailed information from a hindcast and merged altimeter dataset spanning 1992-2014. The waves are driven by winds from the Climate Forecast System Reanalysis and ice concentrations are derived from satellites on a 12.5 km sufficiently able to resolve important features in the marginal ice zone. Effort is taken to identify a suitable forcing wind field, and to establish the validity and consistency of the wave hindcast using buoys and a merged altimeter dataset.

The seasonal advance and retreat of the ice largely dictates the characteristics of the waves. This creates distinct features in the wind seas and swell fields. The Nordic and Greenland Seas are mostly dominated by swell from the North Atlantic while the coastal regions and semi-enclosed seas of the Kara, Laptev, Chukchi, and Beaufort have more of an equal split between wind waves and swell. Trends in the altimeters and model are in agreement and show increasing wave activities in the Beaufort Sea, Chukchi Sea, Laptev Sea, Kara Sea, and Baffin Bay. It is confirmed that the trends are largely related to the loss of ice rather than the change in winds. In the Nordic and Greenland Seas, there are decreasing trends mainly related to the changes in the local wind forcing. The waves also influence the ice sheet. Two distinctly different wave-ice environments are identified: the Greenland Sea and Beaufort/Chukchi Sea. Particular events from these regions are used to demonstrate the impact of storms to the marginal ice zone. The broader implications of the wave-ice interaction will be discussed as they relate to the climate. The crux of the research identifies the need for continued study and improvement of wave-ice interaction.