During the last ice age, there was an ice free corridor wedged between two large ice masses in the Arctic. This corridor, which spanned several hundred kilometres, provided habitats for highly adaptable marine life-forms.
In a new study, scientists from Norway and the UK have shown that, 20.000 years ago, Arctic sea ice in the winter covered more than twice the area than it does today. Yet, there was a small ice-free oasis between ice covered continents and the frozen ocean. There, marine life prevailed.
“When we were looking for evidence of biological life in sediments at the bottom of the ocean, we found that between the sea ice covered oceans, and the ice sheets on land, there must have been a narrow ice-free corridor that extended over hundreds of kilometres into the Arctic. Such ice-free regions are often called “polynyas” – a Russian expression for an area of open water that is surrounded by sea ice and/or ice sheets”, says research scientist Jochen Knies from CAGE and Geological Survey of Norway.
The new findings, which were published recently in Nature Communications, also reveal that the polynya was sustained for at least 5000 years, when the surroundings were largely covered by ice, and global ocean circulation was at a minimum.
Read more at CAGE - Center for Arctic Gas Hydrate, Climate and Environment
Image: Sea ice marginal zone in front of West Antarctic ice sheet. Polynias, ice free corridors between the sea ice and land based ice sheets, are common in Antarctica today. (Credit: Photo: M. Forwick)