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Showing posts with label temperature. Show all posts
Showing posts with label temperature. Show all posts

Wednesday, December 11, 2013

Antarctica sets low temperature record of -135.8 degrees

recordlowap.jpg FILE: In this image provided by the National Snow and Ice Data Center, sastrugi stick out from the snow surface in this photo near Plateau Station in East Antarctica. A new look at NASA satellite data revealed that Earth set a new record for coldest temperature recorded in East Antarctica. It happened in August 2010 when it hit -135.8 degrees. Then on July 31 of this year, it came close again: -135.3 degrees.NSIDC/AP

WASHINGTON –  Feeling chilly? Here's cold comfort: You could be in East Antarctica which new data says set a record for "soul-crushing" cold.

Try 135.8 degrees Fahrenheit below zero; that's 93.2 degrees below zero Celsius, which sounds only slightly toastier. Better yet, don't try it. That's so cold scientists say it hurts to breathe.

A new look at NASA satellite data revealed that Earth set a new record for coldest temperature recorded. It happened in August 2010 when it hit -135.8 degrees. Then on July 31 of this year, it came close again: -135.3 degrees.

The old record had been -128.6 degrees, which is -89.2 degrees Celsius.

Ice scientist Ted Scambos at the National Snow and Ice Data Center said the new record is "50 degrees colder than anything that has ever been seen in Alaska or Siberia or certainly North Dakota."

"It's more like you'd see on Mars on a nice summer day in the poles," Scambos said, from the American Geophysical Union scientific meeting in San Francisco Monday, where he announced the data. "I'm confident that these pockets are the coldest places on Earth."

However, it won't be in the Guinness Book of World Records because these were satellite measured, not from thermometers, Scambos said.

"Thank God, I don't know how exactly it feels," Scambos said. But he said scientists do routinely make naked 100 degree below zero dashes outside in the South Pole, so people can survive that temperature for about three minutes.

Most of the time researchers need to breathe through a snorkel that brings air into the coat through a sleeve and warms it up "so you don't inhale by accident" the cold air, Scambos said.

On Monday, the coldest U.S. temperature was a relatively balmy 27 degrees below zero Fahrenheit in Yellowstone, Wyo., said Jeff Masters, meteorology director of the private firm Weather Underground.

"If you want soul-crushing cold, you really have to go overseas," Scambos said in a phone interview. "It's just a whole other level of cold because on that cold plateau, conditions are perfect."

Scambos said the air is dry, the ground chilly, the skies cloudless and cold air swoops down off a dome and gets trapped in a chilly lower spot "hugging the surface and sliding around."

Just because one spot on Earth has set records for cold that has little to do with global warming because it is one spot in one place, said Waleed Abdalati, an ice scientist at the University of Colorado and NASA's former chief scientist. Both Abdalati, who wasn't part of the measurement team, and Scambos said this is likely an unusual random reading in a place that hasn't been measured much before and could have been colder or hotter in the past and we wouldn't know.

"It does speak to the range of conditions on this Earth, some of which we haven't been able to observe," Abdalati said.


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Sunday, June 26, 2011

Researchers take dinosaurs' temperature with teeth

A Camarasaurus tooth from the Jurassic Morrison Formation of North America, in a photo courtesy of Caltech. REUTERS/Lance Hayashida/Caltech

A Camarasaurus tooth from the Jurassic Morrison Formation of North America, in a photo courtesy of Caltech.

Credit: Reuters/Lance Hayashida/Caltech

By Steve Gorman

LOS ANGELES | Fri Jun 24, 2011 9:28am EDT

LOS ANGELES (Reuters) - Scientists in California say they have for the first time devised a way to accurately take the body temperatures of dinosaurs -- by examining the creatures' teeth.

Chemical analysis of the Jurassic period fossil teeth from two sauropods -- long-tailed, long-necked dinosaurs that rank among the largest land animals ever to roam the Earth -- showed they were about as warm as most modern mammals.

But they also were cooler than some experts had predicted for animals of such gigantic size.

The findings from a team led by researchers at the California Institute of Technology were published Thursday in an online edition of the journal Science.

"This is like being able to stick a thermometer in an animal that has been extinct for 150 million years," said Robert Eagle, an evolutionary biologist and post-doctoral scholar at Caltech who was lead author of the report.

The study supports a growing body of research suggesting dinosaurs were more active and energetic than scientists originally believed.

But it leaves unanswered the key question of whether dinosaurs were cold-blooded, relying on their environments for heat, or warm-blooded, with self-regulated metabolism like modern mammals and their evolutionary descendants, birds.

Eagle said that determination will have to come with further analysis of a much greater range of dinosaur species.

The two dinosaurs initially selected for study -- Brachiosauraus brancai and camarasaurus -- were close cousins of the massive plant-eating dinosaur known as brontosaurus.

The temperature of brachiosaurus was measured at 38.2 degrees Celsius, or 100.8 degrees Fahrenheit. Camarasaurus registered a temperature of 35.7 degrees C, or 96.3 degrees F. Researchers say those figures are accurate to within 2 degrees Celsius.

WARMER THAN CROCS, COOLER THAN BIRDS

While equivalent to the temperature of most modern mammals, that range is warmer than modern and extinct crocodiles and alligators but cooler than birds.

Still, because of their sheer enormous size, sauropod dinosaurs would be expected to retain their body heat more efficiently than smaller warm-blooded animals, like humans, even if dinosaurs themselves were cold-blooded, Eagle said.

To explain this, researchers suggested the dinosaurs may have had some physiological or behavioral adaptation that allowed them to avoid getting too hot. One possibility is they dissipated excess heat through their long necks and tails.

In any case, scientists will learn more as they apply their new technique to other species, such as meat-eating predators like Tyrannosaurus rex or velociraptors, which were smaller and probably faster on their feet, Eagle said.

Researchers previously had to gauge dinosaur body temperatures indirectly, inferring energy needs and metabolism from the spacing of fossil footprints that indicated how fast they ran, or the presumed ratio of predators to prey in the fossil record.

Eagle's more direct technique was adapted from geological research perfected by other Caltech scientists, he said. It examines concentrations of rare carbon and oxygen isotopes in a mineral found in tooth enamel and bone.

Researchers based their study on an examination of 11 fossil teeth unearthed in Tanzania, Wyoming and Oklahoma and donated by museums.

Eagle said his team started with sauropods because their plant-munching teeth were bigger and contained more enamel to work with. Sauropod teeth are also easier to come by in the fossil world, in part because museums and collectors are less willing to part with the teeth of dynamic predator species like T. rex, he said.

(Editing by Jerry Norton)


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