At http://phys.org/print289048472.html … new evidence suggests the Arctic Ocean was circulating much the same as it is now during the last Ice Age – how can this be if the northern hemisphere was covered in a massive ice sheet and the Arctic was locked in ice?
The study is in Nature where we learn the deep Arctic Ocean has been churning happily for at least the last 35,000 years. The discovery comes from the sea floor sediments and seems to indicate there was considerable melting of sea ice in the Arctic Ocean each summer, as today. This appears to contradict the idea there was an enormous body of ice at the top of the world. We may also note the Bering Straits were not open and dry land and therefore the circulation of water must have come via the North Atlantic – thought to be covered in sea ice most of the time