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Me wrote:Extreme Conditions Create Rare Antarctic Clouds
SYDNEY (Aug. 1) - Rare, mother-of-pearl colored clouds caused by extreme weather conditions above Antarctica are a possible indication of global warming, Australian scientists said on Tuesday.
Known as nacreous clouds, the spectacular formations showing delicate wisps of colors were photographed in the sky over an Australian meteorological base at Mawson Station on July 25.
Australian Antarctic Division scientist Andrew Klekociuk said such clouds are occasionally produced by air rising over Arctic and Antarctic mountains in high polar latitudes during winter.
"You have to be in the right part of the world in winter, and have the sun just below your horizon to see them," he said.
Nacreous clouds can only form in temperatures lower than minus 112 Fahrenheit.
Meteorologist Renae Baker said a weather balloon in the vicinity of the clouds in the stratosphere about 12 miles above the Earth's surface measured temperatures as low as minus 124.6 F.
"That's about as cold as the lowest temperatures ever recorded on the surface of the Earth," Baker, who photographed the clouds, said in a statement.
Klekociuk said the rarely seen clouds, also known as polar stratospheric clouds, were more than just a curiosity.
"They reveal extreme conditions in the atmosphere, and promote chemical changes that lead to destruction of vital stratospheric ozone," he said.
Klekociuk said temperatures in the stratosphere, between 5 and 31 miles above Earth, would be expected to drop as global warming increases. Data collected over the past 25 years had reflected this, he told Australian Broadcasting Corp. radio.
"Over that time there has been a small decrease in temperature and that change is actually occurring faster than the warming at the surface of the Earth," he said.
The delicate cloud colors are created at sunset when fading light passes through tiny water-ice crystals blown along on strong jets of stratospheric air.
She said winds at the same height were measured blowing at almost 143 mph.
A Bit of History for Global Warmers: Look at 1930
By Randy Hall
CNSNews.com Staff Writer/Editor
August 04, 2006
(CNSNews.com) - People sweltering from a heat wave in the Mid-Atlantic region of the U.S. might find cold comfort in the fact that the temperatures of the past few days are not the hottest on record. That "honor" belongs to a summer 76 years ago -- decades before the controversy over "man-made global warming" began.
"From June 1 to August 31, 1930, 21 days had high temperatures that were 100 degrees or above" in the metropolitan Washington, D.C., area, Patrick Michaels, senior fellow for environmental studies at the libertarian Cato Institute, told Cybercast News Service. "That summer has never been approached, and it's not going to be approached this year."
Between July 19 and Aug. 9 of that year, heat records were set on nine days and they remain unbroken more than three-quarters of a century later. "That's hot," added Michaels, who also serves as professor of natural resources at Virginia Polytechnic Institute and State University in Blacksburg, Va.
The summer of 1930 also marked the beginning of the longest drought of the 20th century. In 1934, dry regions stretched from New York and Pennsylvania across the Great Plains to California. A "dust bowl" covered about 50 million acres in the south-central plains during the winter of 1935-1936.
However, the first six months of this year were the hottest across the nation since the federal government began keeping records in 1890, according to Dennis Feltgen, a meteorologist with the National Oceanic and Atmospheric Administration who told NBC News that about 50 all-time high-temperature records were broken during the month of July.
But Michaels noted that high temperatures are common in the middle of the summer.
"Climatologically, the last week in July is the warmest week of the year on average, and when the atmospheric flow patterns get into anomalously warm configurations during this time of the year, temperatures will skyrocket," he said.
Along with an unusual upper-air pattern, the Washington, D.C., area "was exceedingly dry" during the summer of 1930, Michaels stated.
"Generally speaking, when the ground is moist here, temperatures cap out in the high 90s," he noted. "That's because the sun's energy is divided into evaporating water and directly heating the surface. If the surface is dry, then everything goes into heating the surface, and you get exceedingly hot temperatures like you saw in 1930.
"Big cities are getting warmer -- with or without global warming -- because the bricks and the buildings and the pavement retain heat," Michaels added. For that reason, he prefers to compare temperatures in nearby rural areas. "There's been very little change" in those areas, "so we trust the record to be a reliable indicator of base climate."
Residents of the nation's capital can look forward to some relief, as weather forecasts for the weekend call for a cooling trend. "If we were going to go into the 100s -- the 103 and 104 degree range -- we would have done it, but there's just a little bit too much moisture in the surface to allow that to happen," Michaels said. He noted, however, that temperatures are expected to rise again next week.
The mid-summer temperatures have provided more opportunities for environmentalists subscribing to the theory that man is responsible for the current global warming.
Jay Gulledge, senior research fellow for science and impacts at the Pew Center on Global Climate Change, told NBC News on Wednesday that "this heat wave and other extreme events we've seen in recent years are completely consistent with what we expect to become more common as a result of global warming, even though we can't be definitive on any single event."
Michaels acknowledged that "global temperatures have been warming slightly for several decades" and noted that the surface of the world "is a little bit warmer than it was in the 1930s" even though "temperatures dropped between 1940 and 1975."
"Usually, the way the jet stream breaks out is very hot in the East and relatively cool in the West or vice versa," he said. "This time around, it looks more like the summers of the 1930s," but he dismissed the idea that the extreme temperatures of that time were caused by man-made "global warming" since "it wasn't around then."
August 03, 2006
Americans Not Warming to Al Gore
Forty-eight percent view him favorably
by Joseph Carroll
A recent USA Today/Gallup Poll finds that Americans' views of Al Gore are unchanged, though he has received a great deal of publicity for his well-received documentary on global warming. Forty-eight percent of Americans have a favorable opinion of Gore while 45% have an unfavorable opinion, compared with a 49% favorable rating in 2003. Gore's ratings were consistently higher during his two terms as vice president than in the last several years.
