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A HEATING DEBATE
Right now, global warming is a hot news topic. While the media seems quick to publicize information supporting its existence, research questioning the existence of global warming often receives little or no coverage. "Temperatures nationwide rose about one degree in the 20th century..." ---The New York Times The New York Times is not the only newspaper guilty of ignoring the scientific debate as to whether the earth's temperatures are rising. The Washington Post and USA Today have cited similar statistics. The fact is, many scientists still question the existence and/or severity of global warming. Temperature statistics vary. The National Oceanic and Atmospheric Administration's surface air temperature record, which is a composite of temperature measurements taken at ground level stations in populated areas of the world, shows that the overall global temperature has increased 0.35° F per decade since the mid-1970s. NASA's satellite record, which uses microwave-sounding units to include the temperature measurements of remote deserts, oceans and rain forests, shows no temperature change in the lower troposphere since 1979. Dr. Vincent Gray, who received his Ph.D. in Physical Chemistry from Cambridge University and served as an Expert Reviewer on the United Nations-sponsored Intergovernmental Panel of Climatic Change (IPCC), points to the satellite information as evidence that no global temperature change is occurring. "The most convincing evidence of all (that the earth is not warming) is that the only truly global temperature measurement system with a known level of accuracy, the MSU units on NASA satellites, has failed to register a temperature change in the lower troposphere for the past twenty years," said Dr. Gray. "If the greenhouse effect were real, this is where it ought to happen." Some scientists hold moderate beliefs about the severity of global warming. Dr. Roy Spencer is a senior scientist for Climate Studies at NASA's Marshall Space Flight Center. His studies involve satellite temperature measurements. "Global warming is occurring and is inevitable," said Dr. Spencer, who considers global warming any amount of natural or man-made warming of the earth, "but I don't believe it is a catastrophic event." When asked which temperature record is more accurate, Dr. Spencer admits he doesn't know. "Both have different kinds of errors," he said. "I believe that climate researchers that believe in (the event of) global warming think they know more than they do," Dr. Spencer concludes. "It's my opinion that they are--without sufficient evidence." "Increasingly, mainstream scientists are concluding that a buildup of heat-trapping gases like carbon dioxide in the atmosphere has contributed to warming in the last 100 years, and they say the trend is likely to carry well into the new century." --The New York Times "Mainstream scientists," who The Times did not identify, must be focusing their studies on the surface air temperature record. Apparently, an IPCC Expert Reviewer and NASA do not fall into The Times' category of "mainstream science." Dr. Gray's studies uncovered an "upward bias" in the surface air temperature record. "Most of the biases from poor supervision are upwards," said Dr. Gray. "Poor cleaning, painting, clearing of cobwebs, control of surrounding vegetation, adequate distance from buildings or roads are examples and inadequate calibration of equipment is another." Dr. Gray finds that population increase and the expansion of human activity may also cause the warming trends observed at ground level temperature measurement stations. "The recent rise since 1976 can be attributed to the escalation of air traffic, the rapid improvement in living standards and the closing of many rural stations," said Dr. Gray. "There is still a lack of representative surface coverage, mainly in the more remote land areas and oceans." John Daly is an economist and scientific advisor of the Greening Earth Society in connection with Western Fuels Association. He is an accomplished global warming debater and has published 10 books questioning its existence, including "Waiting for Greenhouse" and "The Luke-Warm Greenhouse." Most recently, Daly has written a treatise addressing the differences in temperature measurement record trends. The treatise gives three possible explanations for the discrepancy: the surface air record is inaccurate, the satellite record is inaccurate or both records are accurate, and their differing trends are the result of some unknown atmospheric process or processes. "Good maintenance is essential if the instruments are to provide a continuously accurate (surface air temperature) record," said Daly. "Numerous stations across the world have closed since about 1980, at a time when governments sought to cut public services expenditures." Temperature station closures may reduce the consistency of the surface air measurements. "Some of the growth in these so-called greenhouse gases, scientists say, is caused by the burning of fossil fuels, destruction of forests and other human activities." -- The New York Times Dr. Spencer believes that an increase in CO2 "would be harmful in some ways and benign in others." Daly concludes, "Since CO2 has only marginal climatic effects and big biological benefits, there is a net benefit both economically and environmentally to continue using fossil fuels." Global warming calculations: Temperature Trend Calculator Satellite Information
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