Warming Arctic could teem with life by 2030

“Teeming with life” may not be the description that springs to mind when thinking of the Arctic Ocean, but that could soon change as global warming removes the region’s icy lid.

A study of what the Arctic looked like just before dinosaurs were wiped off the planet has provided a glimpse of what could be to come within decades.
Alan Kemp of the UK National Oceanography Centre in Southampton and colleagues used powerful microscopes to inspect cores of mud extracted from the bottom of the Arctic Ocean. They found successive layers of tiny algae called diatoms. The pattern of the layers and the distribution of the diatoms provides strong evidence that the Arctic was free of ice during the summer and, contrary to recent studies, frequently covered in ice during the winter.

Ice-free summers and icy winters are precisely what glaciologists fear could happen in the Arctic within decades. Over the past few years, wind pattern and warm temperatures have been gradually thinning Arctic sea ice, making it less and less likely to survive the summer. Some believe the Arctic could be ice-free during the summer as soon as 2030.

The researchers say that the sheer number of diatoms locked in the mud suggests that when the dinosaurs roamed the Earth the Arctic Ocean was biologically very rich during the summer, on a par with the most productive regions of the Southern Ocean today. Since diatoms are at the very bottom of the food chain, waters rich in diatoms can support a lot of larger life forms as well.

New Scientist