Earth Policy Institute
http://www.earth-policy.org/Books/Seg/PB2ch01_ss2.htm
Lester R. Brown
We recently entered a new century, but we are also entering a new world, one where the collisions between our demands and the earth’s capacity to satisfy them are becoming daily events. It may be another crop-withering heat wave, another village abandoned because of invading sand dunes, or another aquifer pumped dry. If we do not act quickly to reverse the trends, these seemingly isolated events will occur more and more frequently, accumulating and combining to determine our future.
Resources that accumulated over eons of geological time are being consumed in a single human lifespan. We are crossing natural thresholds that we cannot see and violating deadlines that we do not recognize. These deadlines, determined by nature, are not politically negotiable.
Nature has many thresholds that we discover only when it is too late. In our fast-forward world, we learn that we have crossed them only after the fact, leaving little time to adjust. For example, when we exceed the sustainable catch of a fishery, the stocks begin to shrink. Once this threshold is crossed, we have a limited time in which to back off and lighten the catch. If we fail to meet this deadline, breeding populations shrink to where the fishery is no longer viable, and it collapses.
We know from earlier civilizations that the lead indicators of economic decline were environmental, not economic. The trees went first, then the soil, and finally the civilization itself. To archeologists, the sequence is all too familiar.
Our situation today is far more challenging because in addition to shrinking forests and eroding soils, we must deal with falling water tables, more frequent crop-withering heat waves, collapsing fisheries, expanding deserts, deteriorating rangelands, dying coral reefs, melting glaciers, rising seas, more-powerful storms, disappearing species, and, soon, shrinking oil supplies. Although these ecologically destructive trends have been evident for some time, and some have been reversed at the national level, not one has been reversed at the global level.
The bottom line is that the world is in what ecologists call an “overshoot-and-collapse” mode. Demand has exceeded the sustainable yield of natural systems at the local level countless times in the past. Now, for the first time, it is doing so at the global level. Forests are shrinking for the world as a whole. Fishery collapses are widespread. Grasslands are deteriorating on every continent. Water tables are falling in many countries. Carbon dioxide (CO2) emissions exceed CO2 sequestration.
In 2002, a team of scientists led by Mathis Wackernagel, who now heads the Global Footprint Network, concluded that humanity’s collective demands first surpassed the earth’s regenerative capacity around 1980. Their study, published by the U.S. National Academy of Sciences, estimated that global demands in 1999 exceeded that capacity by 20 percent. The gap, growing by 1 percent or so a year, is now much wider. We are meeting current demands by consuming the earth’s natural assets, setting the stage for decline and collapse.
In a rather ingenious approach to calculating the human physical presence on the planet, Paul MacCready, the founder and Chairman of AeroVironment and designer of the first solar-powered aircraft, has calculated the weight of all vertebrates on the land and in the air. He notes that when agriculture began, humans, their livestock, and pets together accounted for less than 0.1 percent of the total. Today, he estimates, this group accounts for 98 percent of the earth’s total vertebrate biomass, leaving only 2 percent for the wild portion, the latter including all the deer, wildebeests, elephants, great cats, birds, small mammals, and so forth.
Ecologists are intimately familiar with the overshoot-and-collapse phenomenon. One of their favorite examples began in 1944, when the Coast Guard introduced 29 reindeer on remote St. Matthew Island in the Bering Sea to serve as the backup food source for the 19 men operating a station there. After World War II ended a year later, the base was closed and the men left the island. When U.S. Fish and Wildlife Service biologist David Kline visited St. Matthew in 1957, he discovered a thriving population of 1,350 reindeer feeding on the thick mat of lichen that covered the 332-square-kilometer (128-square-mile) island. In the absence of any predators, the population was exploding. By 1963, it had reached 6,000. He returned to St. Matthew in 1966 and discovered an island strewn with reindeer skeletons and not much lichen. Only 42 of the reindeer survived: 41 females and 1 not entirely healthy male. There were no fawns. By 1980 or so, the remaining reindeer had died off.
Like the deer on St. Matthew Island, we too are overconsuming our natural resources. Overshoot leads sometimes to decline and sometimes to a complete collapse. It is not always clear which it will be. In the former, a remnant of the population or economic activity survives in a resource-depleted environment. For example, as the environmental resource base of Easter Island in the South Pacific deteriorated, its population declined from a peak of 20,000 several centuries ago to today’s population of fewer than 4,000. In contrast, the 500-year-old Norse settlement in Greenland collapsed during the 1400s, disappearing entirely in the face of environmental adversity.
Even as the global population is climbing and the economy’s environmental support systems are deteriorating, the world is pumping oil with reckless abandon. Leading geologists now think oil production may soon peak and turn downward. Although no one knows exactly when oil production will peak, supply is already lagging behind demand, driving prices upward.
Faced with a seemingly insatiable demand for automotive fuel, farmers will want to clear more and more of the remaining tropical forests to produce sugarcane, oil palms, and other high-yielding biofuel crops. Already, billions of dollars of private capital are moving into this effort. In effect, the rising price of oil is generating a massive new threat to the earth’s biological diversity.
As the demand for farm commodities climbs, it is shifting the focus of international trade concerns from the traditional goal of assured access to markets to one of assured access to supplies. Countries heavily dependent on imported grain for food are beginning to worry that buyers for fuel distilleries may outbid them for supplies. As oil security deteriorates, so, too, will food security.
As the role of oil recedes, the process of globalization will be reversed in fundamental ways. As the world turned to oil during the last century, the energy economy became increasingly globalized, with the world depending heavily on a handful of countries in the Middle East for energy supplies. Now as the world turns to wind, solar cells, and geothermal energy in this century, we are witnessing the localization of the world energy economy.
The world is facing the emergence of a geopolitics of scarcity, which is already highly visible in the efforts by China, India, and other developing countries to ensure their access to oil supplies. In the future, the issue will be who gets access to not only Middle Eastern oil but also Brazilian ethanol and North American grain. Pressures on land and water resources, already excessive in most of the world, will intensify further as the demand for biofuels climbs. This geopolitics of scarcity is an early manifestation of civilization in an overshoot-and-collapse mode, much like the one that emerged among the Mayan cities competing for food in that civilization’s waning years.
You do not need to be an ecologist to see that if recent environmental trends continue, the global economy eventually will come crashing down. It is not knowledge that we lack. At issue is whether national governments can stabilize population and restructure the economy before time runs out.
Thursday, October 11, 2007
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