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Politics : The Environmentalist Thread -- Ignore unavailable to you. Want to Upgrade?

To: Thomas A Watson who wrote (23176)	10/27/2008 12:50:55 PM
From: FJB	Respond to of 36917

If you thought that was funny, you will love this... October 27, 2008 Nuclear-powered passenger aircraft 'to transport millions' says expert timesonline.co.uk Call for big research programme to help aviation industry convert from fossil fuels to nuclear energy The United States experimented with a nuclear reactor aboard a B-36 jet bomber Ben Webster, Transport Correspondent Nuclear-powered aircraft may sound like a concept from Thunderbirds, but they will be transporting millions of passengers around the world later this century, the leader of a Government-funded project to reduce environmental damage from aviation believes. The consolation of sitting a few yards from a nuclear reactor will be non-stop flights from London to Australia or New Zealand, because the aircraft will no longer need to land to refuel. The flights will also produce no carbon emissions and therefore make no contribution to global warming. Ian Poll, Professor of Aerospace Engineering at Cranfield university, and head of technology for the Government-funded Omega project, is calling for a big research programme to help the aviation industry convert from fossil fuels to nuclear energy. In a lecture at the Royal Aeronautical Society tonight, Professor Poll will say that experiments conducted during the Cold War have already demonstrated that there are no insurmountable obstacles to developing a nuclear-powered aircraft. The United States and the Soviet Union both began developing nuclear-powered bombers in the 1950s. The idea was that these bombers would remain airborne, within striking distance of their targets, for very long periods. The United States tested a nuclear-powered jet engine on the ground and also carried out flight tests with a nuclear reactor on board a B-36 jet with a lead-lined cockpit over West Texas and Southern New Mexico. The reactor “ran hot” during the flights but the engines were powered by kerosene. The purpose of the flights was to prove that the crew could be safely shielded from the reactor. Each flight was accompanied by an aircraft packed with marines ready to respond to a crash by parachuting down and securing the area. The test programmes were abandoned in the early 1960s when the superpowers decided that intercontinental ballistic missiles made nuclear-powered planes redundant. In an interview with The Times, Professor Poll said: “We need to be looking for a solution to aviation emissions which will allow flying to continue in perpetuity with zero impact on the environment. “We need a design which is not kerosene-powered, and I think nuclear-powered aeroplanes are the answer beyond 2050. The idea was proved 50 years ago, but I accept it would take about 30 years to persuade the public of the need to fly on them.” Professor Poll said the big challenge would be to demonstrate that passengers and crew could be safely shielded from the reactors. “It's done on nuclear submarines and could be achieved on aircraft by locating the reactors with the engines out on the wings,” he said. “The risk of reactors cracking open in a crash could be reduced by jettisoning them before impact and bringing them down with parachutes.” He said that, in the worst-case scenario, if the armour plating around the reactor was pierced there would be a risk of radioactive contamination over a few square miles. “If we want to continue to enjoy the benefits of air travel without hindrance from environmental concerns, we need to explore nuclear power. If aviation remains wedded to fossil fuels, it will run into serious trouble,” he said. “Unfortunately, nuclear power has been demonised but it has the potential to be very beneficial to mankind.” Professor Poll said an alternative to carrying nuclear reactors on aircraft would be to develop aircraft fuelled by hydrogen extracted from sea water by nuclear power stations. However, he said that while hydrogen could be suitable for ground-based transport, its energy density was much lower than kerosene and it would be very difficult to design a long-range passenger aircraft capable of carrying enough of the fuel. Rob Coppinger, technical editor of Flight International magazine, said it was more likely that nuclear reactors would be installed on unmanned air vehicles, used for reconnaissance or in combat, because there would be less need for heavy shielding than on a passenger plane. Professor Poll will also present research tonight into measures to improve the efficiency over the next decade of short-haul aircraft such as the Boeing 737 and the Airbus A320. He will say that the replacements for these aircraft are likely to fly more slowly, adding about 10 minutes to a typical flight within Europe. They are also likely to have open-rotor engines, which would use 20 per cent less fuel but could be much noisier than existing jet engines.

To: Thomas A Watson who wrote (23176)	10/27/2008 6:27:11 PM
From: Maurice Winn	2 Recommendations Respond to of 36917

What the CO2 crowd don't focus on is the water cycle which turns Earth into a giant refrigeration system. Way back in 1987 for our 12 year old son's school project we described it and how the Greenhouse Effect was trivial compared with H2O phases [vapour, water and ice] and movement [evaporation, vapour convection and drift, cloud drift, precipitation, river and glacier flows, ocean flows]. But there is also plant life which is an essential part of the water cycle and global warming [green absorbs LOTS of light whereas white clouds, snow and desert reflect it]. Your dew point graphs emphasize the dramatic nature and importance of the water cycle. As they show, huge amounts of water can be held in the atmosphere in hot regions where water evaporates in vast quantities. The atmosphere then ships the water laden air north and south where it reaches dew point and then precipitation point. If it falls as water, it runs back down to the oceans, going through the cycle again, but on the way overland, it waters plants and keeps them green, thereby absorbing CO2 and the green acts as a light absorber, keeping Earth warm. If it falls as snow, it turns into kilometres-deep stored water at the poles. Or, it melts after a while, before which it acts as a reflector, preventing light absorption. So, Earth is a giant refrigeration-heating system with plants, clouds and snow cover acting as mobile adjustment mechanisms. When Earth gets colder [for orbital or Sol output or volcanic or other reasons] the snow cover shifts southwards as does the dew point and cloud formation, which increases reflection and accelerates the cooling. Plants get buried by snow, reducing light absorption as the ratio of desert to plants increases. Snow and cloud increase too, further reducing light absorption and increasing cooling. As the snow and cloud cover move toward the equator, they cover more and more ground, increasing reflection. But the increasing sun as the snow and cloud cover extend towards the equator makes it harder and harder for them to gain ground. Meanwhile, plants migrate south [not individuals of course, but their offspring who leave home and find a place where the grass is greener, so to speak]. The southern hemisphere is largely irrelevant from a plant migration point of view due to there being little land there by comparison. But ice over ocean increases around Antarctica and on land masses of course such as New Zealand, Australia, South America. As plants migrate into previously desert areas which have cooled and got wet due to dew point migration, they absorb more light and heat over increasing areas of land. Eventually ice and plants rebalance closer to the equator. Then plants gain ascendancy, covering vast swathes of equatorial desert regions, including the Sahara, Iraq, Australia. All that green causes warming which melts the edge of the permafrost, which allows more plants to grow, causing more warming, and more melting and more plants to grow and more sea water to be exposed which absorbs a LOT of light [heat], and the ice age rolls back in a big hurry as the plants go stampeding across the landscape back towards the poles. With carbon having been stripped from the ecosphere over umpty eons, and being buried in limestone, coal, shale, oil, gas, tars, the atmosphere has a thin gruel of CO2 for plants to feed on and run the water and carbon cycles. That's why the ice age dominates in recent times in Earth's history. When the atmosphere was more substantial at the beginning of the carboniferous period, life could have a lot of fun and was rampant. Now it's a battle for survival against ice. People have put a tiny amount of the carbon back into circulation. But it's not much and it's being stripped from the atmosphere quickly by the green and hungry chlorophyll crowd. That's a brief summary. I hasten to add that process does NOT imply that Earth is in some sort of harmonious balance favouring life. It is not. Life is stripping the CO2 from the ecosphere and permanently burying it, with the end point being a frozen wasteland with a thin atmosphere. We can go on to add volcanoes to the mix because they regurgitate a lot of subducted organic material which falls onto the ocean floor and trundles across to the recycling zones under the edge of the tectonic plates. That adds some long cycles to the process because it takes a LONG time for radiolarian ooze and other organic detritus to travel from mid ocean to a subduction zone. Mqurice