The Arctic winter of 2005-2006 was highly unusual around the Svalbard area: warm Atlantic waters from the West Spitsbergen Current penetrated into the traditionally cold coastal waters around Svalbard and disrupted the normal cycle of sea ice formation. Much of the fjords around the archipelago remained uncharacteristically ice free for much of the winter season. A paper published in this week’s issue of Geographical Research Letters found that this was caused primarily by the arctic coastal waters being exchanged by warm water from ocean currents originating in the Atlantic.  This exchange was ultimately powered by sustained periods of strong winds over the West Spitsbergen shelf which caused the warm upwelling.

Finlo Cottier from SAMS and lead author of the study explained:
“Clearly the Arctic winter conditions of 2005-06 were exceptional in terms of the ice, ocean and atmosphere.  However, the consequences of warm coastal waters go far beyond just the sea ice cover.  Exchange of water also means an exchange of species – particularly the small zooplankton which forms the basis of much of the arctic ecosystem.  Long-term changes in circulation could bring long-term ecological change with a shift in species distribution and viability.”

Finlo Cottier and Frank Nilsen would like to thank The Royal Society for travel grants during the writing process.

Paper: Wintertime warming of an Arctic shelf in response to large-scale
atmospheric circulation. By F. R. Cottier, M. E. Inall, F. Nilsen, S. Gerland, V. Tverberg, and H. Svendsen,  Geophysical Research Letters (GRL) paper 10.1029/2007GL029948, 2007