Thursday, November 14, 2013

pacific ocean warming faster...,


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.