Study Documents Rise in Polar Bears' Long-Distance Swims - NYTimes.com

Now comes a new study from researchers at the United States Geological Survey and the World Wildlife Fund indicating, after tracking a small sample of bears wearing radio collars, that the swims have indeed grown longer over the last six years.

How much longer? What's the baseline data? How long were the swims in 1922?  How do we know that fluctuations in swim length are caused by fluctuations in atmospheric CO2?

You ask, I provide. November 2nd, 1922. Arctic Ocean Getting Warm; Seals Vanish and Icebergs Melt. | Watts Up With That?

[Nov 1922] The Arctic ocean is warming up, icebergs are growing scarcer and in some places the seals are finding the water too hot, according to a report to the Commerce Department yesterday from Consul Ifft, at Bergen, Norway.
Reports from fishermen, seal hunters and explorers, he declared, all point to a radical change in climate conditions and hitherto unheard-of temperatures in the Arctic zone. Exploration expeditions report that scarcely any ice has been met with as far north as 81 degrees 29 minutes. Soundings to a depth of 3,100 meters showed the gulf stream still very warm.
Great masses of ice have been replaced by moraines of earth and stones, the report continued, while at many points well known glaciers have entirely disappeared. Very few seals and no white fish are found in the eastern Arctic, while vast shoals of herring and smelts, which have never before ventured so far north, are being encountered in the old seal fishing grounds.