?Physicist Richard Feynman in the final report on the Challenger disaster Life has had to deal with environmental change, especially climate change, since the beginning of its existence on Earth. Species adjust or go extinct, and both have happened. For life-forms with our kinds of cells?eukaryotic, the kind with distinct organelles?the average existence of a species is about 1 million years, and, on average, one species goes extinct a year, at least of the species we have named and know, including those we know only from fossil records. Organisms adjust to environmental change in three ways, from fastest to slowest: behaviorally, physiologically, and genetically. Ecologist Larry Slobodkin used to demonstrate the first two playfully during a lecture by picking up a piece of chalk and tossing it to one of the students. The student would duck or catch the chalk, which Larry pointed out was the behavioral response, first and fastest, and then within 20 seconds would blush, the physiological adjustment, second fastest. These, he would explain, were not only relatively fast but used little energy in a population. If these failed to make a successful adjustment, a population's genetic makeup could change, with genes transmitted to the next generation that led to characteristics better adjusted to the changed environment, obviously a much slower adjustment. Individual mobile organisms migrate as an adjustment to climate. Plants and other non-mobile species adjust by having seeds or other propagules that move easily. Wind, water, and animals provide the major transportation. In any population there is a mixture of genetic types and, as Darwin explained a long time ago now, those better adapted to the current climate left more offspring than the less adapted, and over time a population evolved to fit the new climate. But this genetic adjustment took time, and since the climate is always changing, it could be that at any one time a population would be adjusting genetically to a climate that had been present but had passed or was passing. It was and is an eternal dance, populations never quite in perfect harmony with their present environment. If the rate of environmental change is too fast, populations cannot adjust and go extinct. Dealing with environmental change has always been part of being alive. Early man was part of this dance between life and environment. Homo erectus, the first of our kind who left Africa, would likely have migrated as a matter of course. They may not have thought of it as migration in our modern sense; they were going where the environment, including sources of food and water, was better. Environmental change and moving along with it were only natural. With the beginning of civilization and the construction of buildings that could last a long time, and with investments of time and effort in agricultural fields, as well as the discovery of specific sources of minerals and the building of mines to get them, people's lives changed in ways that led to a desire for constancy. Establishment of property rights and national boundaries (beginning with tribe-established land boundaries) augmented the need and desire for constancy of place and of environment. One can argue that it is our species that most needs and most desires constancy and has therefore formed worldviews that not only require environmental constancy but have turned it into a fundamental belief, a folkway, a series of myths. The more technologically and legally advanced a civilization, the greater the need and desire for environmental stability, for a balance of nature. Hence, our modern dilemma vis-?-vis climate change. Rather than claim the world is constant except for our sinful interference with it, we need to acknowledge and work out ways to live with environmental change. This can include doing our best to stop or slow that change, as we do in the short term with agricultural irrigation, stabilizing the "precipitation," so to speak. But the harder we work to force environmental constancy onto our surroundings, the more fragile that constancy becomes and the greater the effort and energy it takes. The use of groundwater for crop irrigation illustrates that fragility. Large aquifers that took many thousands of years to develop are being depleted for crop irrigation over comparatively short times?decades or centuries. A major example of this depletion is the Ogallala aquifer (also called the High Plains aquifer), stretching from South Dakota into Texas. It stores a huge amount of water and is the main water source in the area. Its use began in the 1940s. Today water is removed up to 20 times faster than it is naturally replaced. In southwest Kansas and the panhandle in western Texas, it is said that supplies may last only another decade. Lower Cimarron Springs, famous in the nineteenth century as a watering hole along the Santa Fe Trail, dried up decades ago due to pumping groundwater. Millions of dollars will be needed to find alternative sources. Achieving short-term stability at the cost of long-term fragility is a trade-off. It makes more sense, in retrospect, that the earliest civilizations, like Egypt and Persia, were established downstream on a river system whose flow varied year to year but was relatively constant compared to much of the rest of the surrounding lands. When I give talks about the discordant harmonies of nature and my changing views of global warming, a common response is "Why bother to point this out? Everybody believes in global warming, and doing something about it doesn't hurt anything and can only benefit." But in our real world, the choice to take one action means that other actions are not taken. We are well aware these days of the worldwide limits of capital and cash to do things, and we must choose carefully. There's the rub. One of the things missing from the global-warming debate is to put the issue of global warming within the set of major environmental problems and then establish priorities based on what can be done, what needs the most immediate action, and what is most important. In addition to possible effects on climate, major ways that human actions are decreasing overall biological diversity, include (not in an order of priority) habitat destruction; overharvesting of renewable living resources; chemical pollution; removal of groundwater; depletion of mineral resources necessary for life, especially sources of phosphate; and introduction of exotic species that harm other species and are undesirable from our point of view, and just plain inadvertently causing species to become threatened with extinction. These are here-and-now problems. Moreover, sometimes actions that the public is told will help mitigate or reduce global warming create or worsen other environmental problems. For example, in Indonesia, 44 million acres (18 million hectares) of tropical rain forests may have been cut down to plant palm trees to produce palm oil to be used as a biofuel. This is justified as being good for the environment because it is supposed to reduce emissions of greenhouse gases and therefore reduce the rate of global warming. But this habitat destruction further endangers orangutans and Sumatran tigers, already threatened with extinction. While few, if any, knowledgeable environmental organizations will be fooled by the claim that this is going to be environmentally beneficial, the European Union and the government of Malaysia have been considering what to do about the biofuels from these plantations, taking the possibility seriously that using these to fuel cars and trucks in Europe will offset some of the greenhouse gas production by these vehicles and is therefore justified and on the whole environmentally sound. Singling out global warming from other environmental issues is a one-factor approach, which has been too common in environmental policy decisions. For example, as the Clean Water America Alliance points out, the use of water resources requires considerable energy, but water use and energy use are treated as separate issues most of the time in environmental policy analysis. Because global warming gets so much attention and so much funding, this single-factor approach is a particularly important aspect of this issue's policy analysis. In many cases, actions to help solve another environmental problem can also be beneficial in reducing undesirable effects of climate change. For example, as I discuss in Powering the Future: A Scientist's Guide to Energy Independence, moving away from fossil fuels toward wind and solar energy reduces the human contribution of greenhouse gases to the atmosphere while also reducing habitat destruction (from the mining of fossil fuels) and air, water, and ocean pollution (from the mining, processing, and burning of these fuels), benefiting biodiversity and human health and well-being. The same can be said for a move away from fission-based nuclear power plants, whose toxic substances last up to millions of years (the U.S. government is seeking a warning sign that will keep people away from nuclear waste dumps for 10,000 years). The politicization and ideology-driven beliefs about global warming, on both sides of the issue, prevent a calm, rational examination of where actions to mitigate global warming could fit into a set of priorities. Indeed, even making a claim that such prioritizing is possible leads to a change in viewpoints and will likely upset many who believe now that global warming is a present and future reality with disastrous effects. We need to be able to put the discussion within a rational context. Among other aspects of this context, we need, as Thomas Friedman wrote on September 14, 2011, in the New York Times, "to start taking steps, as our scientists urge, 'to manage the unavoidable and avoid the unmanageable.'" Not just about climate change, but in establishing an integrated, multifactor approach to our major environmental problems. Excerpt from?The Moon in the Nautilus Shell: Discordant Harmonies Reconsidered,?by Daniel B. Botkin. Oxford University Press, 2012. Copyright ? 2012. Reprinted with permission. Follow Scientific American on Twitter @SciAm and @SciamBlogs. Visit ScientificAmerican.com for the latest in science, health and technology news.
? 2012 ScientificAmerican.com. All rights reserved.
Source: http://news.yahoo.com/used-climate-change-excerpt-150100813.html
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