usatoday | "We're pumping heat into the ocean at a faster rate over the past 60
years," said study lead author Yair Rosenthal, a climate scientist at
Rutgers University. "We may have underestimated the efficiency of the
oceans as a storehouse for heat and energy," he added. "It may buy us
some time — how much time, I don't really know. But it's not going to
stop climate change."
"It's not so much the magnitude of the
change, but the rate of change," noted study co-author Braddock Linsley,
a Columbia University climate scientist. "We're experimenting by
putting all this heat in the ocean without quite knowing how it's going
to come back out and affect climate."
He said that in the past six
decades the temperature of the Pacific Ocean water studied (from the
surface to about 2,200 feet below) has increased by about one-third of a
degree Fahrenheit. (The specific area studied was in the Pacific near
Indonesia, chosen because that's a typical sample of Pacific Ocean
water.) Researchers say that while the amount of warming might seem
small in the scheme of things, it's the rate of warming that's so
alarming, Linsley said.
The researchers found that Pacific Ocean
water has generally been cooling over the past 10,000 years, until about
800 years ago, when temperatures started to slowly rise. (Then fell
again, during the so-called Little Ice Age from the mid-1500s to
mid-1800s). It's been only in the past few decades, though, that the
rate has dramatically increased.
The Earth's atmosphere has been
about the same temperature for the past 15 years or so, providing fuel
for skeptics of man-made global warming. However, this study, along with
other recent research, finds that heat absorbed by the planet's oceans
has increased significantly.
Obviously, there were no
thermometers taking measurements of ocean temperatures over the past few
thousand years (instrument records from buoys go back only to the
1960s). So scientists had to use "proxy" sources to measure temperature.
In this case, it was fossils of ancient marine life — little shelled
animals known as foraminifera — that could be analyzed to reconstruct
the climates in which they lived over millennia.
"This is a relatively new way of measuring past temperature data," Rosenthal noted.
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