Floating Puzzles in Deep Time
The earth’s climate history is filled with odd twists. Clearly something is going on which can’t be explained by a regular cycle. For example, why did Antarctica freeze over thirty-four million years ago while ice started forming in the Arctic a mere three million years ago? Scientists at the Woods Hole Oceanographic Institute have a fascinating explanation you can find here at Oceanus Magazine:
"From sediment cores and other data, we know that until about 5 million years ago, North and South America were not connected. A huge gap–the Central American Seaway–allowed tropical water to flow between the Atlantic and Pacific Oceans.
A growing body of evidence suggests that the formation of the Isthmus of Panama partitioned the Atlantic and Pacific Oceans and fundamentally changed global ocean circulation."
(Originally posted by R. Guenette on 08./29./06)