The debate about global warming has grown ever more intense in recent years and become as much political as it is scientific. There's no doubt that Earth is warming-- the scientific evidence shows that the planet's temperature has been rising for the past century and a half. But there's disagreement about the extent to which humans are responsible for the change. How alarmed should we be by the warming and by the forecasts of its potentially disastrous consequences?
Rushing to Judgment
by Jack M. Hollander
Is Earth warming? The planet has warmed since the mid-1800s, but before that it cooled for more than five centuries. Cycles of warming and cooling have been part of Earth's natural climate history for millions of years. So what is the global warming debate about? It's about the proposition that human use of fossil fuels has contributed significantly to the past century's warming, and that expected future warming may have catastrophic global consequences. But hard evidence for this human contribution simply does not exist; the evidence we have is suggestive at best. Does that mean the human effects are not occurring? Not necessarily. But media coverage of global warming has been so alarmist that it fails to convey how flimsy the evidence really is. Most people don't realize that many strong statements about a human contribution to global warming are based more on politics than on science. Indeed, the climate change issue has become so highly politicized that its scientific and political aspects are now almost indistinguishable. The United Nations Intergovernmental Panel on Climate Change (IPCC), upon which governments everywhere have depended for the best scientific information, has been transformed from a bona fide effort in international scientific cooperation into what one of its leading participants terms "a hybrid scientific/political organization."
Yet apart from the overheated politics, climate change remains a fascinating and important scientific subject. Climate dynamics and climate history are extraordinarily complex, and despite intensive study for decades, scientists are not yet able to explain satisfactorily such basic phenomena as extreme weather events (hurricanes, tornadoes, droughts), El Nino variations, historical climate cycles, and trends of atmospheric temperatures. The scientific uncertainties about all these matters are great, and not surprisingly, competent scientists disagree in their interpretations of what is and is not known. In the current politicized atmosphere, however, legitimate scientific differences about climate change have been lost in the noise of politics.
For some, global warming has become the ultimate symbol of pessimism about the environmental future. Writer Bill McKibben, for example, says, "If we had to pick one problem to obsess about over the next 50 years, we'd do well to make it carbon dioxide." I believe that we'd be far wiser to obsess about poverty than about carbon dioxide.
Fossil fuels (coal, oil, and natural gas) are the major culprits of the global warming controversy and happen also to be the principal energy sources for both rich and poor countries. Governments of the industrial countries have generally accepted the position, promoted by the IPCC, that humankind's use of fossil fuels is a major contributor to global warming, and in 1997 they forged an international agreement (the Kyoto Climate Change Protocol) mandating that worldwide fossil fuel use be drastically reduced as a precaution against future warming. In contrast, the developing nations for the most part do not accept global warming as a high-priority issue and, as yet, are not subject to the Kyoto agreement. Thus, the affluent nations and the developing nations have set themselves on a collision course over environmental policy relating to fossil fuel use.
The debate about global warming focuses on carbon dioxide, a gas emitted into the atmosphere when fossil fuels are burned. …