This December, world leaders will meet in Kyoto, Japan to sign an amendment to the United Nations Framework Convention on Climate Change (the Rio Treaty) that will require signatory nations to meet strict targets and timetables for reducing their emissions of carbon dioxide and other greenhouse gases. The central premise of the amendment -- and the treaty itself -- is that atmospheric concentrations of these gases are growing at an alarming rate and that continued build-up of these gases will result in a rise in global temperatures. Such warming, treaty proponents argue, could lead to such calamities as world-wide flooding, droughts, pestilence, agricultural disasters and famine, the spread of tropical diseases such as malaria and increases in the intensity and frequency of severe weather disturbances such as hurricanes, to name only a few. The scientific foundation for all these claims, however, is rather weak.
Nevertheless, President Clinton appears poised to sign the Kyoto amendment. The costs of doing so could be high for the United States as the amendment is likely to call for reductions in current greenhouse gas emissions of between 10 and 20 percent by the year 2020. By one estimate, even reducing U.S. emission to their 1990 levels would reduce gross domestic product by $260 billion per year, equal to $2,700 per household.
Unfortunately, the Intergovernmental Panel on Climate Change (IPCC), the U.N.-sponsored body tasked with studying global climate data, has given us little reason to believe such high costs are justified. Before the United States places the economic futures of hundreds of thousands if not millions of Americans at risk in the interest of stopping the threat of global warming, the American people are entitled to answers to some basic, common-sense questions. These questions include: 1) Would life be better with or without global warming?; 2) Is global warming actually occurring?; 3) Is global warming the result of natural phenomenon or human activity?; and 4) Is the prescribed cure for global warming worse than the disease?
Perhaps the most important, most fundamental question of all is whether life would be better with or without global warming.
Question #1: Would life be better with or without global warming?
After world leaders meet in Kyoto, Japan this December, billions of people may face a bleaker future than they do today. The principal threat comes not from the possibility that the international community will fail to adopt a plan to control global warming, but that it will actually succeed in doing so.
The Benefits of Global Warming
According to the World Bank, one-third of the world's population already suffers from chronic water shortages. The Worldwatch Institute predicts that this situation will be exacerbated further by the addition of an estimated 2.6 billion people to the world's population over the next 30 years. By 2025, the group claims, some three billion people -- or 40% of the world's population -- could be living in countries without sufficient water supplies, leading to crop failures, diminished economic development and even to regional conflicts as nations find it necessary to fight for control over scarce water resources.
While the scientific community is divided over many aspects of the global warming theory, the effect of global warming on precipitation levels is not one of them: Global warming would mean more condensation and more evaporation, producing more and/or heavier rains. Global warming, therefore, could offer the answer to the water scarcity problem that the Worldwatch Institute has been seeking.
If history is any indication, greater precipitation may be only one of many benefits of global warming. For example, between the 10th and 12th Centuries, when the temperature of the planet was roughly 0.5 degrees Celsius warmer than it is today, agriculture in North America and Europe flourished and the southern regions of Greenland were free of ice, allowing cultivation by Norse settlers. Evidence of this was found in 1993 when scientists from the National Science Foundation-sponsored Greenland Ice Sheet Project II extracted an ice core from Greenland's ice sheet that spanned more than 100,000 years of climate history. Samplings from the core suggest that a Little Ice Age began between 1400 and 1420, blanketing the Vikings' farms in ice and forcing them to abandon their farms in search of more hospitable climates. Prior to the onset of this Little Ice Age, temperatures were comparable to the temperatures general circulation models used by the U.N.-sponsored Intergovernmental Panel on Climate Change (IPCC) have projected for 2030-2050. Yet, the world's leaders stand poised to take dramatic steps to curb the risks of this kind of climate change.
Global warming could also mean greater agricultural productivity and greater water conservation. CO2 acts as a fertilizer on plant life while reducing plant transpiration (the passage of water from the roots through the plant's vascular system to the atmosphere). Thus, with global warming, agricultural output could be expected to increase while making less demands on the water supply.
The Myth of Increased Storm Activity
Proponents of swift, coordinated international action to counter the threat of global warming counter that the phenomenon could both increase the intensity and frequency of storms and boost the populations of such pests as mosquitoes, increasing the risk of malaria, yellow fever and other diseases. But there is little evidence to support either conclusion.
Since 1492, eight of the twenty "deadliest" tropical storms in the Atlantic occurred prior to 1850, the year most cited as the beginning of the current planetary warming trend. The deadliest of these storms occurred in 1780 offshore of Martinique and Barbados and cost an estimated 22,000 lives. Only two of the top 20 deadliest storms occurred since 1963 and none of them occurred in the 1980s or 1990s, when the earth reportedly experienced its hottest temperatures on record (See figure 1).
Figure 1: Twenty Deadliest Tropical Storms in the Atlantic
Year ------- Countries/Area Effected ------- Deaths
1780 West Indies: Barbados, Martinique 22,000 1900 Galveston, Texas 8,000-12,000 1974 Honduras 8,000-10,000 1930 Dominican Republic 4,000-8,000 1963 Haiti and Cuba 7,000-8,000 1776 Pointe-a-Pitre Bay 6,000 1775 Newfoundland Banks 4,000 1899 Puerto Rica and the Carolinas 3,000-4,000 1928 Florida, Guatemala, Puerto Rico, Turks and Caicos Island, and Martinique 3,000-4,000 1932 Cuba, Cayman Islands, and Jamaica 2,500-3,100 1782 Central Atlantic 3,000 1813 Martinique 3,000 1934 El Salvador and Honduras 2,000-3,000 1791 Western Cuba 3,000 1831 Barbados 1,500-2,500 1931 Belize 1,500-2,500 1935 Haiti, Honduras, and Jamaica 1,000-2,000 1979 Dominica and United States 2,000 1781 Offshore Florida 2,000 1893 South Carolina and Georgia 1,000-2,500
According to the George C. Marshall Institute, severe storms are more closely associated with cold weather than warm weather. The most severe storms in the North Sea, for example, occurred during the 15th and 16th centuries, after the onset of the Little Ice Age. Storms in 1421 and 1446 claimed 100,000 lives while a storm in 1570 claimed over 400,000.
The Myth of Increased Disease
Claims that higher global temperatures would lead to increased risk of malaria, dengue, yellow fever and other tropical diseases are similarly weak. The Intergovernmental Panel on Climate Change (IPCC) projects, under its worst case warming scenario, that the world population at risk of malaria transmission could increase by one-third by the end of the next century. But the greatest human health risks in the future will come not from contact with insects, but with other humans, according to leading authorities.
"The combination of population growth, international air travel, incessant migration and the ebb and flow of refugees means that the peoples of the world are more intermingled now than at any time in history," writes the United Nations's World Health Organization. "Thus, human transmission could become the predominant way in which diseases are spread quickly, not just from person to person but from continent to continent -- by airborne and droplet spread, sexual transmission, bloodborne transmission or direct contact."
Even the IPCC, which through its reports and press releases has fueled much of the international hysteria over global warming, admits that the impact of global warming is uncertain. In its 1995 Summary for Policymakers, the IPCC stated: "Impacts are difficult to quantify and existing studies are limited in scope... quantitative projections of the impacts of climate change on any particular system at any particular location are difficult because regional-scale climate change predictions are uncertain; our current understanding of many critical processes is limited and systems are subject to multiple climatic and non-climatic stresses, the interactions of which are not always linear or additive."
In other words, the IPCC really doesn't know whether global warming would be desirable or not.
Historical record, however, suggests that it would be.
Question #2: Is global warming occurring?
Whether or not the planet is warming depends largely on the time period measured. The planet has experienced numerous warming and cooling trends throughout its history. If the starting point for temperature measurement is the 16th century, for example, then global temperatures have decreased, not increased. If, however, the starting point is the middle of the 19th century at the conclusion of the Little Ice Age, then the planet has warmed by roughly 1.5 degrees Celsius. But there is little evidence that this warming trend has continued appreciably over the past 50 years.
According to climate models used as the basis of the U.N. Framework Convention on Climate Change, by now global mean temperatures were supposed to be rising at a rate of 0.3 degrees Celsius per decade. But no such warming has occurred, forcing modelers to consistently revise their projections downward.
An article by Richard Kerr in the September 9, 1994 issue of Science offers an explanation of why: In order for a climate model to have credibility, it must first be able to reliably "predict" current climate. According to Kerr, "nearly everybody cheats a little" to achieve these results by manipulating their models to make them agree with today's temperatures. Some "tune" their models by adjusting the strength of solar radiation; others by adjusting the transfer of energy between the ocean and the atmosphere to get just the desired results. The result is climate models that are largely worthless.
But the National Center for Atmospheric Research recently developed a climate model without such cheating. The model, which can run for 300 years without deviation from the real climate, projects that doubling of CO2 levels would raise global temperatures just two degrees Celsius, between 20% and 55% less than the increases forecast by the IPCC.
Even modest climate variation like this is subject of some debate among climate scientists. For example, a poll of 400 German, American and Canadian climate researchers conducted by Dennis Bray of the Meteorologisches Institut der Universitat Hamburg and GKSS Forschungszentrum and Hans von Storch of GKSS Forschungszentrum and reported in the United Nations Climate Change Bulletin found that slightly more scientists agreed than disagreed with the premise that global warming is underway. The poll, which surveyed 228 German, 149 American and 35 Canadian scientists involved in climate research, asked scientists to indicate their agreement to the following statement on a scale of one to seven: "We can say for certain that global warming is a process already underway." With one equal to "strongly agree" and seven equal to "strongly disagree," the overall mean response was just 3.3 -- almost dead center. Further, just 3% of U.S. respondents, 13% of German respondents and 23% of Canadian respondents "strongly agreed" that global warming is underway.
The answer to the question of whether or not global warming is underway is therefore uncertain. Global temperatures have risen since the mid-19th century, but available evidence suggests that there has been no significant warming in recent decades and no clear answer to what the future holds.
Question #3: Is global warming the result of natural phenomenon or human activity?
Scientists don't fully understand the role of carbon dioxide on the climate, let alone the role of human emissions of these gases on the climate. Four hundred and forty million years ago, atmospheric concentrations CO2 were up to ten times current levels. Based on IPCC climate models, the temperature during this period should have been between five and eight degrees Celsius warmer than today. Yet, geologic evidence suggests that the period was in the grip of a major ice age, with temperatures five to ten degrees colder than today. This suggests that CO2 levels are only one of many factors effecting global climate.
History similarly shows little solid connection between human CO2 emissions and climate change. Although planet temperature has increased by 1.5 degrees Celsius since the mid-19th century, two-thirds of this rise occurred before 1940, when carbon dioxide emissions from human activities such as fossil fuel consumption were still minimal. Further, according to the Worldwatch Institute, worldwide carbon emissions from fossil fuels reached an all-time high in 1996 of 6.25 billion tons. If such emissions are responsible for global warming one should expect that the rise in human-generated carbon emissions would result in a corresponding rise in the temperature of the planet. They haven't. Despite a more than 19% rise in such emissions since 1979, the planet temperature has cooled slightly over the past 18 years -- by .09 degrees Celsius.
Global warming -- if it is indeed occurring -- appears to be the result of natural process rather than human activity.
Question #4: Is the cure worse than the disease?
The initial objective of international negotiators has been to reduce greenhouse gas emissions to their 1990 levels by the year 2000 (1990/2000 mandate), with further reductions slated for 2010 and 2020. Rolling back carbon dioxide emissions of industrialized nations to their 1990 levels would require carbon taxes of between $100 and $200 per metric ton. A $100 carbon tax would reduce U.S. gross domestic product by between two and four percent by 2010, causing job losses of between 500,000 and one million by some estimates.
Australia, which has a strong mining sector, would fair even worse. The Australian Bureau of Agricultural and Resource Economics has estimated that cutting emissions ten percent below 1990 levels -- a reduction level likely to be called for in Kyoto -- would cost Australians $7,000 each. As a result, Prime Minister John Howard is considering pulling Australia out of the negotiations.
The economies of developing nations, however, would be particularly sensitive to mandated reductions in carbon dioxide emissions. Brazil's emissions grew by 20%, India's grew by 28%, Indonesia's grew by 40% and China's grew by 27% between 1990 and 1995. Developing nations and oil exporters in particular have thus been understandably reticent about joining the effort to limit emissions, fearing that such efforts could jeopardize their economic futures. This may explain why developing nations were exempted from the 1990/2000 reduction mandate under the Berlin Mandate. Over the next two decades, however, as much as 60% of all carbon emissions will come from the developing world, suggesting that strict emission controls on these nations are only a matter of time.
The IPCC has admitted as much: "Clearly, the Convention's ultimate objective of stabilizing global greenhouse gas concentrations at a 'safe' level is not going to be achieved by the presently 'developed countries alone," notes the IPCC in a recent bulletin. "[I]n the longer term their efforts could be negated by the growth of emissions from developing countries."
While full global costs of reducing greenhouse gas emissions are difficult to calculate, the costs would certainly be high and likely outweigh any climate benefits of reducing such emissions.
This December, world leaders will meet in Kyoto, Japan to craft a response to global warming -- a phenomenon that may not even exist, could be a net plus if it does, and may, in any event, be impossible for human beings to control. Nevertheless, they are poised to commit to specific targets and timetables for reducing greenhouse gas emissions at tremendous cost to the world's economies, including those that can afford it least -- the developing world.
The fate of billions of people could hinge on the outcome of the Kyoto meeting. But the principal threat comes not from the possibility that the international community will fail to adopt a plan to control global warming, but that it will actually succeed in doing so.
David A. Ridenour is Vice President of The National Center for Public Policy Research.
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