There's cold, and then there's Antarctica cold. ... How does a frosty reading of 135.8 degrees below zero sound?
Based on remote satellite measurements, scientists recently recorded that temperature at a desolate ice plateau in East Antarctica. It was the lowest temperature ever recorded on Earth, though it may not get that recognition in the official record book.
A NASA satellite measured that temperature in August 2010; on July 31 of this year, another bone-chilling temperature of -135.3 degrees was recorded.
"I've never been in conditions that cold, and I hope I never am," said ice scientist Ted Scambos of the National Snow and Ice Data Center in Boulder, Colo. "I am told that every breath is painful, and you have to be extremely careful not to freeze part of your throat or lungs when inhaling."
The -135.8-degree reading is "50 degrees colder than anything that has ever been seen in Alaska or Siberia or certainly North Dakota," he said.
"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 on Monday, where he announced the data.
Winter in Antarctica occurs, as it does throughout the Southern Hemisphere, in the months of June, July and August, when the continent is in total darkness.
The official record, as measured by a thermometer, remains -128.6 degrees, set in Vostok, Antarctica, on July 21, 1983. The World Meteorological Organization (WMO), the official keepers of world weather records, recognizes only readings measured by thermometers on location, not remotely by satellite.
"Vostok is still the world's coldest recorded location," said Randy Cerveny, an Arizona State University professor of geography and the "rapporteur for climate extremes" at the WMO, via e-mail. "They are using remote sensing, not standard weather stations, so we at the World Meteorological Organization will not recognize that."
Cerveny noted that there is no way to determine the elevation of the remote-sensed value. Official temperature measurements must be made of the air about 7 feet above the ground, to prevent the ground temperature from impacting the air temperature.
Vostok is a Russian research station about 600 miles from the South Pole, where the highest temperature ever recorded was 4 degrees on a summer afternoon.
As for the USA's coldest mark on record, it's -80 degrees, set in Prospect Creek, Alaska, on Jan. 23, 1971, according to Christopher Burt, weather historian for the Weather Underground. Excluding Alaska, the lowest temperature was the -70-degree temperature recorded in Rogers Pass, Mont., in January 1954.
Regardless of whether or not the Antarctica mark is an "official" record, it's still unimaginably cold: "Thank God, I don't know how exactly it feels," Scambos said. He said scientists do routinely make naked 100-degree-below-zero dashes outside at the South Pole, so people can survive that temperature for about three minutes.
Scambos said that in East Antarctica, the air is dry, the ground chilly and the skies cloudless. Cold air swoops down off a dome and gets trapped in a chilly lower spot, "hugging the surface and sliding around."
The Antarctica measurements were made by the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on board NASA's Aqua satellite and by Landsat 8, a satellite launched early this year by NASA and the U.S. Geological Survey.
The record for cold 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 probably an unusual random reading in a place that hasn't been measured much and could have been colder or hotter in the past.
"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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