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Remember how Wile E. Coyote, in his obsessive pursuit of the RoadRunner, would fall off a cliff? The hapless predator ran straightout off the edge, stopped in midair as only an animated charactercould, looked beneath him in an eye-popping moment of truth, andplummeted straight down into a puff of dust. Splat! Four decadesago, a Massachusetts Institute of Technology computer model calledWorld3 warned of such a possible course for human civilization inthe 21st century. In Limits to Growth , a bitterly disputed 1972 book that explicated these findings,researchers argued that the global industrial system has so muchinertia that it cannot readily correct course in response tosignals of planetary stress. But unless economic growth skidded to a halt before reaching theedge, they warned, society was headed for overshoot—and asplat that could kill billions. Don't look now but we are running in midair, a new book asserts. In 2052: A Global Forecast for the Next Forty Years (Chelsea Green Publishing), Jorgen Randers of the BI NorwegianBusiness School in Oslo, and one of the original World3 modelers,argues that the second half of the 21st century will bring us nearapocalypse in the form of severe global warming . Dennis Meadows, professor emeritus of systems policy at theUniversity of New Hampshire who headed the original M.I.T. team andrevisited World3 in 1994 and 2004, has an even darker view. The1970s program had yielded a variety of scenarios, in some of whichhumanity manages to control production and population to livewithin planetary limits (described as Limits to Growth). Meadowscontends that the model's sustainable pathways are no longer withinreach because humanity has failed to act accordingly. Instead, the latest global data are tracking one of the mostalarming scenarios, in which these variables increase steadily toreach a peak and then suddenly drop in a process called collapse.In fact, "I see collapse happening already," he says."Food per capita is going down, energy is becoming morescarce, groundwater is being depleted." Most worrisome,Randers notes, greenhouse gases are being emitted twice as fast asoceans and forests can absorb them. Whereas in 1972 humans wereusing 85 percent of the regenerative capacity of the biosphere tosupport economic activities such as growing food, producing goodsand assimilating pollutants, the figure is now at 150percent—and growing. Randers's ideas most closely resemble a World3 scenario in whichenergy efficiency and renewable energy stave off the worst effectsof climate change until after 2050. For the coming few decades,Randers predicts, life on Earth will carry on more or less asbefore. Wealthy economies will continue to grow, albeit more slowlyas investment will need to be diverted to deal with resourceconstraints and environmental problems, which thereby will leaveless capital for creating goods for consumption. Food productionwill improve: increased carbon dioxide in the atmosphere will cause plants to grow faster, and warming will open up new areas such as Siberiato cultivation. Population will increase, albeit slowly, to amaximum of about eight billion near 2040. Eventually, however,floods and desertification will start reducing farmland andtherefore the availability of grain. Despite humanity's efforts toameliorate climate change, Randers predicts that its effects willbecome devastating sometime after mid-century, when global warmingwill reinforce itself by, for instance, igniting fires that turnforests into net emitters rather than absorbers of carbon."Very likely, we will have war long before we get there,"Randers adds grimly. He expects that mass migration from landsrendered unlivable will lead to localized armed conflicts. Graham Turner of Australia's Commonwealth Scientific and IndustrialResearch Organization fears that collapse could come even earlier,but due to peak oil rather than climate change. After comparing thevarious scenarios generated by World3 against recent data onpopulation, industrial output and other variables, Turner and,separately, the PBL Netherlands Environmental Assessmeng Agency,conclude that the global system is closely following abusiness-as-usual output curve. In this model run the economycontinues to grow as expected until about 2015, but then faltersbecause nonrenewable resources such as oil become ever moreexpensive to extract. "Not that we're running out of any ofthese resources," Turner explains. "It's that as you tryto get to unconventional sources such as under deep oceans, ittakes a lot more energy to extract each unit of energy." Tokeep up oil supply, the model predicts that society will divertinvestment from agriculture, causing a drop in food production. Inthis scenario, population peaks around 2030 at between seven andeight billion and then decreases sharply, evening out at about fourbillion in 2100. The e-commerce company in China offers quality products such as Led Neon Rope Light Manufacturer , Led Track Lighting Fixtures, and more. For more , please visit Led Neon Signs today!
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