Date: Wed, 18 Feb 1998 19:33:24 +0000 From: "M.A.&N.G. Jones" <Jones_M-AT-netcomuk.co.uk> Subject: Re: M-TH: Marine biodiversity and soil fertility F. SHERWOOD ROWLAND Dr. F. Sherwood Rowland, University of California at Irvine. Dr. Rowland won the Nobel Prize in Chemistry in 1995 for his pioneering research in atmospheric chemistry of the destruction of the ozone layer. He currently serves as the Foreign Secretary of the National Academy of Sciences and is a former President and Chairman of the Board of the American Association for the Advancement of Science. Rowland received his Ph.D. from the University of Chicago in 1952 and is currently the Donald Bren Research Professor of Chemistry and Earth System Science at UC Irvine. DR. ROWLAND: Mr. President and Mr. Vice President, global climatic change is underway. Carbon dioxide [CO2] from the combustion of coal, oil, and natural gas has risen by 15 percent in the atmosphere since 1958. Methane, some of which is emitted from cattle and rice paddies, has risen by 16 percent since 1978. The air now holds four times as much chlorofluoracarbons (or CFCs) as it did 25 years ago. The amount of ozone in the stratosphere over the United States is 6 to 10 percent lower than it was in the 1960s. Many other changes are occurring as well. The global average surface temperature has risen about 1 degree Fahrenheit [·F] during the past century, and sea level has risen from 4 to 10 inches. Land use patterns have been greatly altered as forests are burned for use as agricultural land. Many of the biological species formerly in these forests are disappearing. The geographical ranges of tropical diseases are moving northward. Human activities are the chief cause of many of these changes. During the 20th century the developed countries have changed from the agricultural societies of 1900 and to the highly industrialized urban environments of the present. Great forward progress has occurred in the comfort and well being of significant segments of the global population, although not for all. Enormous strides have been made in health. Death rates are lower, life spans are much longer. The last century has also seen a tremendous growth in the global population from about 1½ billion in 1900 to 6 billion in the year 2,000 and 8 billion in the year 2025. Much of the progress and affluence has resulted from the substitution of non-living sources of energy for human and animal energies, [from] the availability of engines, of electricity. Most of this energy comes from the burning of coal, gas, and oil. These energies bring with them environmental consequences: CO2 from the fossil fuels, the radioactivity of nuclear waste. In Japan in 1959, I encountered bullock carts on the road to a nuclear research center. In China in 1980, humans propelled wheelbarrows to move dirt from road construction sites. In contrast, the City of Shanghai alone now has 20,000 major construction projects going simultaneously. And much of the world is moving as fast as possible into a more affluent, energy-intensive era. This combination of a rapidly growing world population with an increase in per capita use of energy carries with it great pressures on the environment and on the atmosphere. Because the wind circles the earth within a few weeks, greenhouse gases emitted from each country quickly become a global problem requiring a global solution. Our earlier experience in dealing with the destruction of stratospheric ozone by the CFCs has taught us that humans can collectively interfere with natural processes on a global scale. Further, despite the immense amount already known about the atmosphere and the oceans, these are complicated systems with uncertainties going in both directions. Surprises can happen. Witness the devastating losses of ozone over Antarctica every spring. However, the United Nations' Montreal Protocol, which is now successfully controlling the emissions of CFCs into the atmosphere, demonstrates that the nations of the world can agree to act when it's for the mutual benefit of all. During the 1990's, these countries have called upon the world's scientists to evaluate the question of global warming from the accumulation of greenhouse gases. In response, the authoritative IPCC [Intergovernmental Panel on Climate Change] has estimated a probable increase in global and surface air temperature of about 3½·F by the year 2100 with a possible range from 2 to 6½·F. They further stated … that the balance of evidence suggests a discernible human influence on global climate, and they warned that the average rate of warming will probably be greater than any experienced in the past 10,000 years. Much of the variations in outcomes depends upon what the countries of the world do to control the emissions of carbon dioxide and other greenhouse gases in the intervening years. More than 2,600 scientists have now signed this Scientists' Statement on Global Climatic Disruption in which as scientists and as concerned citizens we ask that the United States demonstrate strong leadership in the global effort with a firm proposal for reducing U.S. emissions of greenhouse gases. --- from list marxism-thaxis-AT-lists.village.virginia.edu ---
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