Dr. Don J. Easterbrook, Professor Emeritus Geology, Western Wa****ngton
University, author of 8 books, 150 journal publications with focus on
geomorphology; glacial geology; Pleistocene geochronology; environmental
and engineering geology.
CBS-TV, 60 Minutes, Burlington, Wa****ngton
March 30, 2008
http://icecap.us/images/uploads/DonEasterbrookInterviewTranscript.pdf
DJE: There's a big noise that Gore and Hansen made about melting in
Greenland. There is melting along the edges, but the ice is growing in
the middle, like Antarctica. To discuss Greenland temperatures-we had
global warming from the turn of the century to the 1940's, then
Greenland experienced the same global cooling that everyone else did
from 1945 to about 1977 and it's been warming since then. The
interesting thing is, it was warmer in Greenland in the 1930's than it
is right now. They're saying it's never happened before? It happened in
the 1930's.
KLC: Speaking of Greenland, I'm curious about your take as a geologist
about what you see as a driving factor. From my reading I know you
believe there is a correlation with solar cycles, but I'm curious about
the geothermal heating.
DJE: The temperature is too variable to be accounted for by volcanic
activity. Aerosols from eruptions last about two years, and then they're
done. With regard to geothermal heating, there is geothermal activity in
Greenland that may be contributing to the melt, but I suspect the root
cause of melting around the edges is ocean surface temperature. We're in
a global warming period, so what do you expect to happen?
I plotted a curve from isotopes in Greenland. Oxygen isotope ratios give
us ambient air temperature in the snowfall. The isotope signature doesn't
change, so you can core ice and examine annual dust layers that mark the
ablation surface in the summer when the dust settles on it. You can
identify the melt season very accurately and go back for thousands of
years with one or two year accuracy. The chronology is very accurate. We
don't have it in the Antarctic, but we have it in Greenland. I plotted
the Oxygen 18 ratios and they show times when the temperature was warmer
and colder. The cool periods are about 30 years apart, which means the
same thing we saw in the last century has been going on for 500 years.
It's nothing new.
--
Warmest Regards
Bonzo
"From 1870 to 1900, we had global cooling, then we had significant
global warming from about 1910 to 1945. That global warming is not
accompanied by any significant rise in CO2, so you can't blame CO2. Then
CO2 increased while we had global cooling. You can't blame that on CO2.
It's only been the last 30 years there's been correlation between CO2
and global warming" Dr. Don J. Easterbrook, Professor Emeritus Geology,
Western Wa****ngton University
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