The remarkable charts that introduce this book reveal the story of humanity's impact on the natural earth. The pattern is clear: if we could speed up time, it would seem as if the global economy is crashing against the earth -- the Great Collision. And like the crash of an asteroid, the damage is enormous. For all the material blessings economic progress has provided, for all the disease and destitution avoided, for all the glories that shine in the best of our civilization, the costs to the natural world, the costs to the glories of nature, have been huge and must be counted in the balance as tragic loss.
Half the world's tropical and temperate forests are now gone. The rate of deforestation in the tropics continues at about an acre a second. About half the wetlands and a third of the mangroves are gone. An estimated 90 percent of the large predator fish are gone, and 75 percent of marine fisheries are now overfished or fished to capacity. Twenty percent of the corals are gone, and another 20 percent severely threatened. Species are disappearing at rates about a thousand times faster than normal. The planet has not seen such a spasm of extinction in sixty-five million years, since the dinosaurs disappeared. Over half the agricultural land in drier regions suffers from some degree of deterioration and desertification. Persistent toxic chemicals can now be found by the dozens in essentially each and every one of us.
Human impacts are now large relative to natural systems. The earth's stratospheric ozone layer was severely depleted before the change was discovered. Human activities have pushed atmospheric carbon dioxide up by more than a third and have started in earnest the dangerous process of warming the planet and disrupting climate. Everywhere earth's ice fields are melting. Industrial processes are fixing nitrogen, making it biologically active, at a rate equal to nature's; one result is the development of more than two hundred dead zones in the oceans due to overfertilization. Human actions already consume or destroy each year about 40 percent of nature's photosynthetic output, leaving too little for other species. Freshwater withdrawals doubled globally between 1960 and 2000, and are now over half of accessible runoff. The following rivers no longer reach the oceans in the dry season: the Colorado, Yellow, Ganges, and Nile, among others.
Half the world's tropical and temperate forests are now gone. The rate of deforestation in the tropics continues at about an acre a second. About half the wetlands and a third of the mangroves are gone. An estimated 90 percent of the large predator fish are gone, and 75 percent of marine fisheries are now overfished or fished to capacity. Twenty percent of the corals are gone, and another 20 percent severely threatened. Species are disappearing at rates about a thousand times faster than normal. The planet has not seen such a spasm of extinction in sixty-five million years, since the dinosaurs disappeared. Over half the agricultural land in drier regions suffers from some degree of deterioration and desertification. Persistent toxic chemicals can now be found by the dozens in essentially each and every one of us.
Human impacts are now large relative to natural systems. The earth's stratospheric ozone layer was severely depleted before the change was discovered. Human activities have pushed atmospheric carbon dioxide up by more than a third and have started in earnest the dangerous process of warming the planet and disrupting climate. Everywhere earth's ice fields are melting. Industrial processes are fixing nitrogen, making it biologically active, at a rate equal to nature's; one result is the development of more than two hundred dead zones in the oceans due to overfertilization. Human actions already consume or destroy each year about 40 percent of nature's photosynthetic output, leaving too little for other species. Freshwater withdrawals doubled globally between 1960 and 2000, and are now over half of accessible runoff. The following rivers no longer reach the oceans in the dry season: the Colorado, Yellow, Ganges, and Nile, among others.
[ ... ]
Economic historian Angus Maddison reports that in the year 1000 there were only about 270 million people on earth -- fewer than today's U.S. population. Global economic output was only about $120 billion. Eight hundred years later, the man-made world was still small. By 1820, populations had risen to about a billion people with an output of only $690 billion. Over this eight hundred years, per capita income increased by only a couple of hundred dollars a year. But shortly thereafter the take-off began. By 2000, populations had swelled by an additional five billion, and, astoundingly, economic output had grown to exceed forty trillion dollars.[19] The acceleration continues. The size of the world economy doubled since 1960, and then doubled again.
World economic activity is projected to quadruple again by midcentury.
World economic activity is projected to quadruple again by midcentury.
No comments:
Post a Comment