August 25, 2004 · Richard Posner
At last, high-level Administration acknowledgment that global warming is real, and that human activity (mainly the burning of fossil fuels, principally oil, natural gas, and coal, and deforestation in Third World countries) is a principal cause because such activity emits carbon dioxide. (See also Times article.)
Greenhouse gases, such as carbon dioxide, in the atmosphere trap heat reflected from the earth and by doing so maintain a temperate climate. But since the Industrial Revolution and in particular since about 1970, economic and population growth has resulted in greatly increased emissions of carbon dioxide, resulting in greatly increased atmospheric concentrations of the gas (the effect of emissions is largely cumulative, because it takes a long time for carbon dioxide to be removed from the atmosphere, by absorption by the oceans), producing in turn higher global temperatures. As I explain in my forthcoming book Catastrophe: Risk and Response, because the global climate equilibrium is fragile, abrupt global warming is possible, though unlikely, in the near future. It would not be as abrupt as depicted in “The Day After Tomorrow,” but it might be abrupt enough to have catastrophic consequences within a decade or even less, consequences that might include a rise in ocean levels that would inundate most of the world’s coatal areas, where most of the largest cities and much of the world’s population are found.
The current global-warming problem is an artifact of technology (though not of the newest technology), which has not only made carbon the basis of most of our energy but has contributed to a great increase in the number and wealth of people, and hence to a great increase in the demand for energy. But technology may bail us out, either by developing feasible, economical substitutes for carbon-based energy sources, or, by advances in nanotechnology (molecular-scale engineering), creating carbon-dioxide devouring nanomachines to cleanse carbon dioxide out of the atmosphere. Unfortunately, as is so generally the case, technology has a downside; for example, concern has been expressed that the weaponization of nanotechnology could further destabilize the geopoliitcal system, and even that nanomachines might accidentally be created that were incredibly voracious self-replicators–superweeds that might devour all organic matter on the planet. See Nanotechnology.