18:00 15Dec2004 RTRS-Arctic Ocean was balmy 70 mln years ago -study

LONDON, Dec 15 (Reuters) - It may be freezing cold and covered in ice
now but 70 million years ago the Arctic Ocean was as tepid as the
Mediterranean.
In a past greenhouse world, the frigid north would have been balmy,
judging from evidence in a core drilled in an ice island drifting over a
ridge on the ocean floor.
Hugh Jenkyns, of the University of Oxford in England, and scientists
from the Royal Netherlands Institute for Sea Research analysed organic
material in mud in the core and calculated that the mean sea surface
temperature of the Arctic Ocean was 15 degrees Centigrade (59 Fahrenheit)
about 70 million years ago.
"Further back in time if would have been even warmer, so it would have
been a good place to swim," said Jenkyns, who reported the findings in the
journal Nature on Wednesday.
Twenty million years earlier it could have reached 20 degrees Centigrade
(68F).
"It was certainly very much a greenhouse world," he told Reuters.
Although the scientists don't know why it was so warm, they suspect it
may have been due to high concentrations of atmospheric carbon dioxide, the
greenhouse gas blamed for contributing to current global warming.
In a commentary in the journal, Christopher Poulsen, of the University
of Michigan in the United States, said the levels of carbon dioxide were
probably three to six times what they are today which contributed to a
"super-greenhouse climate".
"For a region blanketed in darkness for half of the year, the Arctic
Ocean was astoundingly warm," said Poulsen.

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My comment....

Ever heard of precession? Surely the wobbling of the earth's axis would
affect the angle of theEarth's tilt pointing perhaps more directly towards
the sun.

Brendan