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Science and Health:
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History of Global Warming

On September 14, 2004, British Prime Minister Tony Blair pledged to pressure Washington to take the threat of global warming more seriously. ONEWORLD reported that Blair would urge the United States to "rejoin international negotiations to curb emissions of greenhouse gases in order to reduce the speed at which the Earth's climate is changing." The Prime Minister has named global warming one of his two top priorities for 2005. Since President Bush withdrew from the Kyoto Protocol negotiations in 2001, the United States has stood apart from Britain and other world leaders on this issue. The stakes, and rhetorical flourishes, have only risen after the Kyoto Protocol went into effect on February 16,2005.

When did the idea of "global warming" emerge and when did it enter into political debate? Below, a series of highlights throughout history to help understand how global concern for the effects of climate change developed. Also, learn about the different viewpoints on global warming in the climate debate.

Global Warming in the Public Eye: A Timeline

1904: Swedish scientist Svante Arrhenius was, according to NASA, "the first person to investigate the effect that doubling atmospheric carbon dioxide would have on global climate."

Arrhenius began studying rapid increases in anthropogenic — human-caused — carbon emissions, determining that "the slight percentage of carbonic acid in the atmosphere may, by the advances of industry, be changed to a noticeable degree in the course of a few centuries."

The unique research of Arrhenius suggested that this increase could be beneficial, making Earth's climates "more equable" and stimulating plant growth and food production. Until about 1960, most scientists thought it implausible that humans could actually affect average global temperatures.

1950s: Geophysicist Roger Revelle, with the help of Hans Suess, demonstrated that carbon dioxide levels in the air had increased as a result of the use of fossil fuels.

1965: Serving on the President's Science Advisory Committee Panel on Environmental Pollution in 1965, Roger Revelle helped publish the first high-level government mention of global warming. The book-length report identified many of the environmental troubles the nation faced, and mentioned in a "subpanel report" the potential for global warming by carbon dioxide.

1977: "In 1977 the nonpartisan National Academy of Sciences issued a study called Energy and Climate, which carefully suggested that the possibility of global warming 'should lead neither to panic nor to complacency.' Rather, the study continued, it should 'engender a lively sense of urgency in getting on with the work of illuminating the issues that have been identified and resolving the scientific uncertainties that remain.' As is typical with National Academy studies, the primary recommendation was for more research." — From "Breaking the Global-Warming Gridlock" by Daniel Sarewitz and Roger Pielke Jr., THE ATLANTIC, July 2000

Roger Revelle chaired the National Academy Panel, which found that about forty percent of the anthropogenic carbon dioxide has remained in the atmosphere, two-thirds from fossil fuel and one-third from the clearing of forests. It is now known that carbon dioxide is one of the primary greenhouse gases that contributes to global warming and remains in the atmosphere for a century.

1980s: Representative Al Gore (D-TN), who had been a student of Revelle's, co-sponsored the first Congressional hearings to study the implications of global warming and to encourage the development of environmental technologies to combat global warming.

1982: Roger Revelle published a widely-read article in SCIENTIFIC AMERICAN addressing the rise in global sea level and the "relative role played by the melting of glaciers and ice sheets versus the thermal expansion of the warming surface waters."

1983: The Environmental Protection Agency released a report detailing some of the possible threats of the anthropogenic emission of carbon dioxide.

1988: NASA climate scientist James Hansen and his team reported to Congress on global warming, explaining, "the greenhouse warming should be clearly identifiable in the 1990s" and that "the temperature changes are sufficiently large to have major impacts on people and other parts of the biosphere, as shown by computed changes in the frequency of extreme events and comparison with previous climate trends."

With the increased awareness of global warming issues, the Intergovernmental Panel on Climate Change (IPCC) was established by the World Meteorological Organization and the United Nations Environment Programme to assess scientific, technical and socio-economic information relevant for the understanding of climate change, its potential impacts and options for adaptation and mitigation. The IPCC was the first international effort of this scale to address environmental issues.

1990: Congress passed and President George Bush signed Public Law 101-606 "The Global Change Research Act of 1990. The purpose of the legislation was "…to require the establishment of a United States Global Change Research Program aimed at understanding and responding to global change, including the cumulative effects of human activities and natural processes on the environment, to promote discussions towards international protocols in global change research, and for other purposes."

As part of the Act, the Global Change Research Information Office (GCRIO) was established "to disseminate to foreign governments, businesses, and institutions, as well as citizens of foreign countries, scientific research information available in the United States which would be useful in preventing, mitigating, or adapting to the effects of global change. The office began formal operation in 1993.

1992: In June of 1992, over 100 government leaders, representatives from 170 countries, and some 30,000 participants met in Rio de Janeiro at the U.N. Conference on Environment and Development (UNCED or the "Earth Summit"). There, an international assembly formally recognized the need to integrate economic development and environmental protection into the goal of sustainable development.

1997: In December, 1997, more than 160 nations met in Kyoto, Japan, to negotiate binding limitations on greenhouse gases for the developed nations, pursuant to the objectives of the Framework Convention on Climate Change of 1992. The outcome of the meeting was the Kyoto Protocol, in which the developed nations agreed to limit their greenhouse gas emissions, relative to the levels emitted in 1990. The United States agreed to reduce emissions from 1990 levels by 7 percent during the period 2008 to 2012.

Also that year, the United States Senate unanimously passed the Hagel-Byrd Resolution notifying the Clinton Administration that the Senate would not ratify any treaty that would (a) impose mandatory greenhouse gas emissions reductions for the United States without also imposing such reductions for developing nations, or (b) result in serious harm to our economy.

2001: The IPCC released its third assessment report, concluding on the basis of "new and stronger evidence that most of the observed warming over the last 50 years is attributable to human activities." They also observed that "the globally averaged surface temperature is projected to increase by 1.4 to 5.8 degrees Celsius over the period 1990 to 2100."

The same year, President George W. Bush announced that the United States would not ratify the Kyoto Protocol. The Protocol is now in limbo until one of the two crucial holdouts — Russia or the United States — will ratify the treaty.

2002: The Milan conference of the United Nations Framework Convention on Climate Change was just one in a series of international meetings to negotiate points of the Kyoto Protocol, and the tension surrounding the issue brought both scientists and the energy industry to the table. NOW reported on the conference in "Ode to Kyoto."

2003: Senator John McCain (R-AZ) and Senator Joseph Lieberman (D-CT) co-sponsored a proposal for mandatory caps on "greenhouse gas" emissions from utilities and other industries. Although the proposal was rejected in the Senate by a margin of 55 to 43, it was the Senators' first attempt to garner Senate attention for the issue of global warming, and McCain and Lieberman were encouraged by the support for the measure.

2004: In August, an annual report by the Climate Change Science Program and the Subcommittee on Global Change Research — "Our Changing Planet: The U.S. Climate Change Science Program for Fiscal Years 2004 and 2005" — was submitted to Congress. In what the NEW YORK TIMES called a "striking shift in the way the Bush administration has portrayed the science of climate change," the report indicated that "emissions of carbon dioxide and other heat-trapping gases are the only likely explanation for global warming over the last three decades." Dr. James R. Mahoney, the director of government climate research, told the NEW YORK TIMES that the studies mentioned in the new report are "significant but not definitive."

On September 15, members of the Senate Committee on Commerce, Science and Transportation heard testimony examining recent scientific research concerning climate change impacts. Senator John McCain presided, opening the hearing by explaining:

Last month, I visited the Arctic region and saw first hand the impacts of climate change on the region. These impacts are real and are consistent with earlier scientific projections that the polar regions would experience the effects of climate change at a faster rate than the rest of the globe. The retreating glaciers provide irrefutable evidence supporting the need to take action on this issue. We cannot continue to ignore an issue that is not static. We need to take action that extends well beyond eloquent speeches, and includes meaningful actions such real reductions in the emission of greenhouse gases.

In late 2004, the Bush Administration came into conflict with the world community when it appeared to take issue with parts of an eight-nation report compiled by 250 scientists which contended that the Arctic is warming almost twice as fast as the rest of the planet due to a buildup of heat-trapping gases. The U.S. State Department argued that the group lacked the evidence to prepare detailed policy proposals.

2005: In a January 2005 speech Senator James Inhofe made a speech on the Senate floor again condemning the idea of global warming as "the greatest hoax ever perpetrated on the American people." Inhofe made frequent reference to the fictional work by author Michael Crichton, best known for the rebirth of dinosaurs in JURASSIC PARK, STATE OF FEAR in which eco-terrorists engineer disasters to prove their theories about global warming. (More about global warming and the international media.)

The Kyoto Protocol entered into force on February 16, 2005. Industrialized countries have committed to cut their combined emissions to 5% below 1990 levels by 2008 - 2012. The emissions covered under the treaty are: Carbon dioxide (CO2), Methane (CH4), Hydrofluorocarbons (HFCs), Perfluorocarbons (PFCs), Sulphur hexafluoride (SF6). As of April 19, 2005, 149 states and regional economic integration organizations have deposited instruments of ratifications, accessions, approvals or acceptances. (More about Kyoto.)

SOURCES: United Nations Framework Convention on Climate Change; CBS News; NASA's Earth Observatory; Environmental Research Foundation; THE ATLANTIC; SOCIAL PROBLEMS; Global Change Research Information Office

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