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| CLIMATE CHANGE | |
 May 2004 
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A team of international ecologists using a computer model to predict the effects of climate change say as many as 1 million species could be on the way to extinction by the year 2050. One of the study's authors, Lee Hannah, and environmental experts Daniel Botkin and Patrick Michaels answer your questions.
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Tim Dyke of Honolulu, Hawaii, asks: Can climate change be reversed, as opposed to deterred? If so, how would that happen? What irreparable damage has already been done? Daniel Botkin responds: The best available scientific analyses -- using computer models of climate and studies of past climates and their effects on forests -- suggest that we are very unlikely to reverse the global warming we seem to have initiated, but that we could greatly slow the rate of increase. And it is the rate of climate change that is most important for us and other living things. Life is adapted to climate change, but at much slower rates of change in comparison to what is forecast to happen from global warming. The geological and fossil record suggests that the every rare, very rapid changes in climate, as seem to have occurred when asteroids hit the Earth, were accompanied by great numbers of extinctions of species and great changes in the distribution of other species. Lee
Hannah responds: It is technically possible to remove greenhouse gases from the atmosphere, and this might be part of an interim solution until major changes in transportation and industrial technology can reduce emissions. However, stabilizing (much less reducing) greenhouse gas concentrations requires eliminating all fossil fuel emissions. This is a huge task, so practically it seems unlikely that we'll be able to turn back the clock to greenhouse gas levels of the last century, for instance. Patrick Michaels responds (expanding on a previous answer): That is an excellent question and one that is avoided in discussions of climate change -- it is the real elephant in the room that no one wants to acknowledge. So here's the real answer: We can do very, very little about human-induced climate change. If every nation on earth that signed the Kyoto Protocol on global warming, which reduces emissions in most developed countries roughly 6 percent below 1990 levels by the period 2008-2012, the amount of "saved" warming by 2050 is a mere 0.07 degrees Celsius. Because human-induced warming is a linear (constant-rate) phenomenon, that works out to 0.14 degrees Celsius in a century. Consider that the normal year-to-year variability is about 0.15 degrees Celsius, and you must conclude that we couldn't even find the "signal" of our attempt to slow warming within the year-to-year "noise." That's because any attempt to really "do" anything substantial requires a dramatic shift away from carbon-based energy technologies, a shift that cannot be done with current technology. And solar energy and windmills, so-called "renewable" energy (there really is no such thing as "renewable" energy!) will never be major players because the sun isn't hot enough and the wind too inconstant. Besides, wind power is an esthetic nightmare. So, if something really is to be done, it has to be with a totally different, reliable, productive source of energy. I don't know what that is and neither does anyone else. It could be hydrogen fuel cells, it could be gravity ... beats me. But to get there requires INVESTMENT, which requires capital, which is why laws that take away capital in an attempt to stop warming, like the Kyoto Protocol, are terribly ill-advised. The obvious solution to warming is affluence that creates new technologies, not legally enforced energy privation. I'm not so sure about overall "damage." Consider that, as the world warmed three-quarters of a degree in the last 100 years that life expectancy in developed nations doubled (from roughly 40 to 80 years) and some crop yields quintupled. Wealth has been spread through the population much more so (in terms of actual purchasing power) than the dreams of the wildest social visionaries of the mid-19th century (I include Marx here). Global warming didn't "cause" these changes, but it surely did not stop them. With regard to species distributions, it is clear that habitat fractionation and destruction is much more of a problem than slight climate changes. Remember that climate is very "patchy," with microclimates allowing species to flourish far outside of the range that would be expected from gross climatology (Red spruce, a Canadian tree, is a favorite ornamental in Atlanta, for example), so it is much harder to extinct species from modest climate change than one might expect. Good question!
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