What Precise Source Tells Us About Arctic Sea Ice. Dennis Darby

Sedimentation rates in parts of the Arctic Ocean are surprisingly high with 1-2% of that sediment originating from ‘dirty ice,’ says Professor Emeritus Dennis Darby. He explains various processes that govern the formation of sea ice and how sediment can be entrained in it, the processes and routes by which ‘dirty ice’ is transported throughout the Arctic, and his data base of 38,000 different samples permits tracking sediment collected from the sea floor back to its point of origin. Darby discusses how the extensive record he has assembled “which includes cores from the one Deep Sea Drilling Project effort undertaken in Arctic waters (in coordination with Russian scientists using a nuclear-powered icebreaker)” reveal cycles of deposition that correspond to the Arctic and North Atlantic Oscillation, changes in the Greenland ice sheet and Heinrich events in the North Atlantic.

July 24, 2014