ØProjections of future climate changes are uncertain. Although some computer models predict warming in the next century, these models are very limited. The effects of cloud formations, precipitation, the role of the oceans, or the sun, are still not well known and often inadequately represented in the climate models --- although all play a major role in determining our climate. Scientists who work on these models are quick to point out that they are far from perfect representations of reality, and are probably not advanced enough for direct use in policy implementation. Interestingly, as the computer climate models have become more sophisticated in recent years, the predicted increase in temperature has been lowered.
Are humans causing the climate to change?
Ø98% of total global greenhouse gas emissions are natural (mostly water vapor); only 2% are from man-made sources.
ØBy most accounts, man-made emissions have had no more than a minuscule impact on the climate. Although the climate has warmed slightly in the last 100 years, 70% percent of that warming occurred prior to 1940, before the upsurge in greenhouse gas emissions from industrial processes. (Dr. Robert C. Balling, Arizona State University)
ØA Gallup survey indicated that only 17% of the members of the American Meteorological Society and the American Geophysical Society thought the warming of the 20th century was the result of an increase in greenhouse gas emissions.
If global warming occurs, will it be harmful?
ØThe idea that global warming would melt the ice caps and flood coastal cities seems to be mere science fiction. A slight increase in temperature -- whether natural or mankind induced -- is not likely to lead to a massive melting of the earth ice caps, as sometimes claimed in the media. Also, sea-level rises over the centuries relate more to warmer and thus expanding oceans, not to melting ice caps.
Contrary to some groups' fear mongering about the threat of diseases, temperature changes are likely to have little effect on the spread of diseases. Experts say that deterioration in public health practices such as rapid urbanization without adequate infrastructure, forced large scale resettlement of people, increased drug resistance, higher mobility through air travel, and lack of insect-control programs have the greatest impact on the spread of vector-borne diseases.
ØLarger quantities of CO2 in the atmosphere and warmer climates would likely lead to an increase in vegetation. During warm periods in history vegetation flourished, at one point allowing the Vikings to farm in now frozen Greenland.
Politics
What are the policy proposals?
ØThe U.S. agreed to a 7% reduction of CO2 emissions from what they were in 1990 -- a target to be met by 2008-2012. This agreement would result in massive restrictions on energy use and large taxpayer-funded subsidies for new technologies.
ØThe Clinton Administration has supported a system of tradable permits to be used by companies that emit CO2. These permits could be bought and sold inter-nationally, giving companies an incentive to lower emissions and thus sell their permits. But this system would require massive international oversight on the order of a worldwide EPA to track CO2 emissions, and the costs to consumers would still be high.
ØBecause of the devastating effects that global warming policies will have on economic growth, the treaty that was discussed in Kyoto in December 1997 currently excludes developing nations. However, the US Senate has voted 95-0 against supporting a treaty that doesn’t include developing nations.
What economic impact will the proposals have?
ØAccording to a report by the Department of Energy, stringent targets to reduce fossil-fuel emissions in the US will cause energy-intensive industries, including steel, iron, chemical, rubber and plastic, to flee from the developed countries to undeveloped countries, taking with them hundreds of thousands of jobs.
ØCarbon taxes will cause relatively large income losses in the poorest one-fifth of the population. The poor, because they spend a greater proportion of their income on necessities, would have few ways to cut back to compensate for higher living costs.
ØStabilizing emissions at 1990 levels by 2010 would reduce the growth of US per capita income by 5% per year.(Gary W. Yohe, Wesleyan University)
ØThe burden would fall on many individuals and families and would be unfair in that it would be quite unrelated to income, wealth or ability to pay. Instead, the burden would be determined by energy use patterns and circumstances, such as distance from work, condition and energy efficiency of homes, automobiles, and appliances.
ØSenior citizens on fixed incomes would find their energy costs escalating and their income dwindling.
Will the policies actually stop global warming?
ØBy all estimates, only severe reductions in global CO2 emissions -- on the order of 60 percent or more -- will alter the computer forecasts. The resulting economic dislocations would be tremendous, potentially outweighing the negative impacts of even the most apocalyptic warming scenario.
ØIf the policies do not include developing nations the result will likely be a reallocation of emissions to developing nations, not a reduction of emissions.
ØIf the entire world is included and CO2 emissions are severely restricted, the science is not clear what impact, if any, it would have on the world’s climate.
Claim: Scientists agree that failing to respond to the threat of global warming now could prove disastrous for some parts of the globe.
Fact: A survey of over 400 German, American and Canadian climate researchers conducted by the Meteorologisches Institut der Universitat Hamburg and the GKSS Forschungszentrum found that 67% of those surveyed either disagreed or were uncertain about the proposition that global warming will occur so quickly that lack of preparation could prove disastrous.
Claim: Thousands of scientists have signed letters and petitions alerting the public to the dangers of global warming.
Fact: One of the letters often cited to support this claim was issued by Ozone Action. A close examination of that letter revealed that only 10% of the letter's signatories had backgrounds in climate science. Worse, landscape architects, a gynecologist, and a practitioner of traditional Chinese medicine are among the signatories.
Claim: 2,500 United Nations-sponsored scientists have concluded that human greenhouse gas emissions are warming the temperature of the planet.
Fact: This claim is based on the fact that the United Nations Intergovernment Panel on Climate Change (IPCC) issued a report suggesting a "discernible human influence" on climate change. While several thousand scientists were consulted in crafting the report, not all of them agreed with its conclusions. As Dr. John W. Zillman, one of these scientists noted: "[The IPCC was] meticulous in insisting that the final decision on whether to accept particular review comments should reside with chapter Lead Authors... Some Lead Authors ignored valid critical comments or failed to... reflect dissenting views..." The report was therefore the result of a political rather than a scientific process.
Claim: The majority of scientists believe global warming is a process underway and that it is human-induced.
Fact: A 1992 Gallup survey of climatologists found that 81 percent of respondents believed that the global temperature had not risen over the past 100 years, were uncertain whether or not or why such warming had occurred, or believed any temperature increases during that period were within the natural range of variation. Further, a 1997 survey conducted by American Viewpoint found that state climatologists believe that global warming is largely a natural phenomenon by a margin of 44% to 17%.