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Förre amerikanske vicepresidenten Al Gore släppte nyligen en propagandafilm om den påstådda globala uppvärmningen, "An Inconvenient Truth". Vetenskapsmän världen runt protesterar nu mot Al Gores framställning. Canada Free Press-medarbetaren Tom Harris har sammanfattat kritiken: "Scientists have an independent obligation to respect and present the truth as they see it," Al Gore sensibly asserts in his film "An Inconvenient Truth"... With that outlook in mind, what do world climate experts actually think about the science of his movie? Professor Bob Carter of the Marine Geophysical Laboratory at James Cook University, in Australia: "Gore's circumstantial arguments are so weak that they are pathetic. It is simply incredible that they, and his film, are commanding public attention."... Even among that fraction, many focus their studies on the impacts of climate change; biologists, for example, who study everything from insects to polar bears to poison ivy. "While many are highly skilled researchers, they generally do not have special knowledge about the causes of global climate change," explains former University of Winnipeg climatology professor Dr. Tim Ball. "They usually can tell us only about the effects of changes in the local environment where they conduct their studies." This is highly valuable knowledge, but doesn't make them climate change cause experts, only climate impact experts... But it becomes smaller still. Among experts who actually examine the causes of change on a global scale, many concentrate their research on designing and enhancing computer models of hypothetical futures. "These models have been consistently wrong in all their scenarios," asserts Ball. "Since modelers concede computer outputs are not "predictions" but are in fact merely scenarios, they are negligent in letting policy-makers and the public think they are actually making forecasts."... Appearing before the Commons Committee on Environment and Sustainable Development last year, Carleton University paleoclimatologist Professor Tim Patterson testified, "There is no meaningful correlation between CO2 levels and Earth's temperature over this [geologic] time frame. In fact, when CO2 levels were over ten times higher than they are now, about 450 million years ago, the planet was in the depths of the absolute coldest period in the last half billion years." Patterson asked the committee, "On the basis of this evidence, how could anyone still believe that the recent relatively small increase in CO2 levels would be the major cause of the past century's modest warming?" Patterson concluded his testimony by explaining what his research and "hundreds of other studies" reveal: on all time scales, there is very good correlation between Earth's temperature and natural celestial phenomena such changes in the brightness of the Sun. Dr. Boris Winterhalter, former marine researcher at the Geological Survey of Finland and professor in marine geology, University of Helsinki, takes apart Gore's dramatic display of Antarctic glaciers collapsing into the sea. "The breaking glacier wall is a normally occurring phenomenon which is due to the normal advance of a glacier," says Winterhalter. "In Antarctica the temperature is low enough to prohibit melting of the ice front, so if the ice is grounded, it has to break off in beautiful ice cascades. If the water is deep enough icebergs will form." Dr. Wibjörn Karlén, emeritus professor, Dept. of Physical Geography and Quaternary Geology, Stockholm University, Sweden, admits, "Some small areas in the Antarctic Peninsula have broken up recently, just like it has done back in time. The temperature in this part of Antarctica has increased recently, probably because of a small change in the position of the low pressure systems." But Karlén clarifies that the 'mass balance' of Antarctica is positive - more snow is accumulating than melting off. As a result, Ball explains, there is an increase in the 'calving' of icebergs as the ice dome of Antarctica is growing and flowing to the oceans. When Greenland and Antarctica are assessed together, "their mass balance is considered to possibly increase the sea level by 0.03 mm/year - not much of an effect," Karlén concludes. The Antarctica has survived warm and cold events over millions of years. A meltdown is simply not a realistic scenario in the foreseeable future... Karlén explains that a paper published in 2003 by University of Alaska professor Igor Polyakov shows that, the region of the Arctic where rising temperature is supposedly endangering polar bears showed fluctuations since 1940 but no overall temperature rise. "For several published records it is a decrease for the last 50 years," says Karlén Dr. Dick Morgan, former advisor to the World Meteorological Organization and climatology researcher at University of Exeter, U.K. gives the details, "There has been some decrease in ice thickness in the Canadian Arctic over the past 30 years but no melt down. The Canadian Ice Service records show that from 1971-1981 there was average, to above average, ice thickness. From 1981-1982 there was a sharp decrease of 15% but there was a quick recovery to average, to slightly above average, values from 1983-1995. A sharp drop of 30% occurred again 1996-1998 and since then there has been a steady increase to reach near normal conditions since 2001."