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Politics : PRESIDENT GEORGE W. BUSH -- Ignore unavailable to you. Want to Upgrade?

To: Kenneth E. Phillipps who wrote (704461)	9/28/2005 12:20:08 PM
From: DizzyG	Respond to of 769670

Do you have some sort of research that backs up your claim? Or is this just your personal opinion? Until you can show me some proof, I'll provide some reading material for you: The South Polar Ice Cap of Mars is Melting The south polar ice cap of Mars is receding, revealing frosty mountains, rifts and curious dark spots. Science@NASA -- It's not every day you get to watch a planetary ice cap melt, but this month you can. All you need are clear skies, a backyard telescope, and a sky map leading to Mars. Actually, you won't need the sky map because Mars is so bright and easy to find. Just look south between midnight and dawn on any clear night this month. Mars is that eye-catching red star, outshining everything around it. It's getting brighter every night as Earth and Mars converge for a close encounter on August 27th. Mars has gotten so big in recent weeks that even a backyard telescope will show details on the planet's surface: dust clouds, volcanic terrains, impact basins. Best of all is the polar ice cap. The southern hemisphere of Mars is tipped toward Earth and its bright southern cap, which reflects more sunlight than any other part of the planet, is remarkably easy to see. Don't wait too long to look, though, because the ice is melting. Like Earth, Mars has seasons that cause its polar caps to wax and wane. "It's late spring at the south pole of Mars. The polar cap is receding because the sun is shining on it," explains planetary scientist Dave Smith of the Goddard Space Flight Center. "Southern summer on Mars begins September 29th; by then much of the polar cap will be gone." Watching the polar cap disappear is fun. The shrinking cap develops rifts, dark spots, and a ragged border. Lately, for instance, amateur astronomers using 8-inch and larger telescopes have been watching a frosty mountain range emerge from the ice. Says Smith, "these are the Mountains of Mitchel" -- named after the Ohio astronomer who first spotted them 150 years ago. A bold dark rift called Rimas Australis cuts through the polar ice just south of those mountains. (These features are visible in Thomas Williamson's photograph of Mars at the beginning of this story.) Something else to look for is the "Cryptic region" -- a dark zone hundreds of km wide. Even after the ice above it recedes, the Cryptic region remains remarkably cold according to infra-red cameras onboard NASA's Mars Global Surveyor spacecraft. No one is sure what the Cryptic region is, "but it's probably big enough to see from Earth," notes Smith. Here's an amazing fact: The seasonal polar caps are made of martian air (carbon dioxide or CO2) that freezes during winter. Depending on the time of year, more than a quarter of the martian atmosphere can be found lying on the ground around the poles. As seasons come and go, this CO2 shifts back and forth -- lying on the ground during cold months, floating through the air during warmer months. The world-wide air pressure rises and falls by 25%. For comparison, the air pressure inside a hurricane on Earth is often only a few percent lower than ambient. You can experience a full 25% difference in pressure by traveling from sea level to the top of a 9000 ft (3000 m) mountain. Just try running a 100 yard dash up there. The south polar cap is vaporizing now, which means CO2 is rushing back into the atmosphere. "Remember, though," adds Smith, "there are two polar caps on Mars--north and south. While the south polar cap is vaporizing the north polar cap is growing. It's a balancing act. Overall air pressure will be greatest when there's the least amount of CO2 on the ground." The next such peak is due in early October--that is, early southern summer on Mars. The boost in pressure has some interesting consequences. It won't make the martian atmosphere thick by Earth-standards. At best the air pressure on Mars is 100 times less than Earth. But it might become thick enough in some places for liquid water to flow. Liquid water is normally impossible on Mars because the air pressure is so low. On a warm summer day, ice doesn't melt. It vaporizes. But a small boost in pressure could be enough to allow water to flow under a warm summer sun. Southern summer, therefore, might be a good time for future human explorers to visit. On the other hand, thicker air also encourages dust storms, which are a big problem on Mars. Small dust clouds stirred by sun-warmed winds sometimes grow to encircle the entire planet. In 2001 such a storm lasted for months and frustrated astronomers who couldn't see through the haze. Will that happen again this year? No one knows. When the seasonal polar cap finally vanishes, Smith recommends looking for the permanent polar cap. "The permanent cap is made of frozen water hiding beneath the seasonal cap of CO2," he explains. While the seasonal cap is wide-ranging (90o to 60o latitude) and shallow (only 1-meter deep), the permanent cap is compact and about 3-km deep. "It harbors a mass of water comparable to the mass of the martian moon Phobos." To amateur astronomers peering through telescopes, the water-ice cap will look like a tight white knot within 10o latitude of the pole. Dark "cryptic" spots. Mountainous rifts. A treasure trove of water. There's a lot to look for around the south pole of Mars. Grab a telescope and see for yourself! ----- Editor's note: In this story we talk about the martian polar caps "melting" or "vaporizing." That's not exactly right. A physicist would say more accurately "the polar caps are subliming." In other words, the frozen CO2--better known as "dry ice"--transforms directly from a solid to a gas without going through an intermediate liquid phase. ----- Author: Dr. Tony Phillips The Science Directorate at NASA's Marshall Space Flight Center sponsors the Science@NASA web sites. The mission of Science@NASA is to help the public understand how exciting NASA research is and to help NASA scientists fulfill their outreach responsibilities. rednova.com Diz-

To: Kenneth E. Phillipps who wrote (704461)	9/28/2005 12:24:01 PM
From: DizzyG	Respond to of 769670

The truth about global warming - it's the Sun that's to blame By Michael Leidig and Roya Nikkhah (Filed: 18/07/2004) Global warming has finally been explained: the Earth is getting hotter because the Sun is burning more brightly than at any time during the past 1,000 years, according to new research. A study by Swiss and German scientists suggests that increasing radiation from the sun is responsible for recent global climate changes. Dr Sami Solanki, the director of the renowned Max Planck Institute for Solar System Research in Gottingen, Germany, who led the research, said: "The Sun has been at its strongest over the past 60 years and may now be affecting global temperatures. "The Sun is in a changed state. It is brighter than it was a few hundred years ago and this brightening started relatively recently - in the last 100 to 150 years." Dr Solanki said that the brighter Sun and higher levels of "greenhouse gases", such as carbon dioxide, both contributed to the change in the Earth's temperature but it was impossible to say which had the greater impact. Average global temperatures have increased by about 0.2 deg Celsius over the past 20 years and are widely believed to be responsible for new extremes in weather patterns. After pressure from environmentalists, politicians agreed the Kyoto Protocol in 1997, promising to limit greenhouse gas emissions between 2008 and 2012. Britain ratified the protocol in 2002 and said it would cut emissions by 12.5 per cent from 1990 levels. Globally, 1997, 1998 and 2002 were the hottest years since worldwide weather records were first collated in 1860. Most scientists agree that greenhouse gases from fossil fuels have contributed to the warming of the planet in the past few decades but have questioned whether a brighter Sun is also responsible for rising temperatures. To determine the Sun's role in global warming, Dr Solanki's research team measured magnetic zones on the Sun's surface known as sunspots, which are believed to intensify the Sun's energy output. The team studied sunspot data going back several hundred years. They found that a dearth of sunspots signalled a cold period - which could last up to 50 years - but that over the past century their numbers had increased as the Earth's climate grew steadily warmer. The scientists also compared data from ice samples collected during an expedition to Greenland in 1991. The most recent samples contained the lowest recorded levels of beryllium 10 for more than 1,000 years. Beryllium 10 is a particle created by cosmic rays that decreases in the Earth's atmosphere as the magnetic energy from the Sun increases. Scientists can currently trace beryllium 10 levels back 1,150 years. Dr Solanki does not know what is causing the Sun to burn brighter now or how long this cycle would last. He says that the increased solar brightness over the past 20 years has not been enough to cause the observed climate changes but believes that the impact of more intense sunshine on the ozone layer and on cloud cover could be affecting the climate more than the sunlight itself. Dr Bill Burrows, a climatologist and a member of the Royal Meteorological Society, welcomed Dr Solanki's research. "While the established view remains that the sun cannot be responsible for all the climate changes we have seen in the past 50 years or so, this study is certainly significant," he said. "It shows that there is enough happening on the solar front to merit further research. Perhaps we are devoting too many resources to correcting human effects on the climate without being sure that we are the major contributor." Dr David Viner, the senior research scientist at the University of East Anglia's climatic research unit, said the research showed that the sun did have an effect on global warming. He added, however, that the study also showed that over the past 20 years the number of sunspots had remained roughly constant, while the Earth's temperature had continued to increase. This suggested that over the past 20 years, human activities such as the burning of fossil fuels and deforestation had begun to dominate "the natural factors involved in climate change", he said. Dr Gareth Jones, a climate researcher at the Met Office, said that Dr Solanki's findings were inconclusive because the study had not incorporated other potential climate change factors. "The Sun's radiance may well have an impact on climate change but it needs to be looked at in conjunction with other factors such as greenhouse gases, sulphate aerosols and volcano activity," he said. The research adds weight to the views of David Bellamy, the conservationist. "Global warming - at least the modern nightmare version - is a myth," he said. "I am sure of it and so are a growing number of scientists. But what is really worrying is that the world's politicians and policy-makers are not. "Instead, they have an unshakeable faith in what has, unfortunately, become one of the central credos of the environmental movement: humans burn fossil fuels, which release increased levels of carbon dioxide - the principal so-called greenhouse gas - into the atmosphere, causing the atmosphere to heat up. They say this is global warming: I say this is poppycock." telegraph.co.uk