But actually, an article from today's New York Times says it all better...
U.N. Warns of Urgent Environmental Problems
PARIS, Oct. 25 — The human population is living far beyond its means and inflicting damage to the environment that could pass points of no return, according to a major report being issued today by the United Nations.Climate Change, the rate of extinction of species, and the challenge of feeding a growing population are among the threats putting humanity at risk, according to the United Nations Environment Program in its fourth Global Environmental Outlook since 1997.
“The human population is now so large that the amount of resources needed to sustain it exceeds what is available at current consumption patterns,” Achim Steiner, the executive director of the Environment Program, said in a telephone interview. Efficient use of resources and reducing waste now are “among the greatest challenges at the beginning in of 21st century,” he said.
The program described its report, which is prepared by 388 experts and scientists, as the broadest and deepest of those the United Nations has issued on the environment and called it “the final wake-up call to the international community.”
Over the last two decades the world population has increased by almost 34 percent, to 6.7 billion from 5 billion. But the land available to each person is shrinking, from 19.5 acres in 1900 to 5 acres by 2005, and is projected to drop to 4 acres by 2050, the report said.
Population growth combined with unsustainable consumption has resulted in an increasingly stressed planet where natural disasters and environmental degradation endanger millions of human beings as well as plant and animal species, the report said.
Persistent problems identified by the report include a rapid rise of so-called dead zones, where marine life no longer can be supported due to depleted oxygen levels from pollutants such as fertilizers, as well as the resurgence of diseases linked with environmental degradation.
The report comes two decades after a commission chaired by the former Norwegian prime minister warned that the survival of humanity was at stake from unsustainable development.
Mr. Steiner said many of the problems the Brundtland Commission identified are even more acute because not enough had been done to stop environmental degradation while flows of goods, services, people, technologies and workers has expanded, even to isolated populations.
He did, however, identify pockets of hope, noting that Western European governments had taken effective measures to reduce air pollutants and that Brazil had made efforts to roll back some deforestation in the Amazon. He said an international treaty to tackle the hole in the earth’s ozone layer had led to the phasing out 95 percent of ozone-damaging chemicals.
Mr. Steiner said parts of Africa could reach an environmental tipping point if changing rainfall patterns stemming from climate change turned semi-arid zones into arid zones and made agriculture that sustains millions of people much harder.
Mr. Steiner said another tipping point could occur in India and China if Himalayan glaciers shrink so much that they no longer supply adequate amounts of water to populations in those countries.
He also warned of a global collapse of all species being fished by 2050, if fishing around the world continued at its present pace.
The report said 250 percent more fish are being caught than the oceans can produce in a sustainable manner, and that global fish stocks classed as collapsed had roughly doubled to 30 per cent over the past 20 years.
The report said that current changes in biodiversity were the fastest in human history, with species becoming extinct a hundred times faster than the rate in the fossil record. It said 12 percent of birds are threatened with extinction; for mammals the figure is 23 percent and for amphibians it is more than 30 percent.
The report said concentrations of carbon dioxide in the atmosphere were about one-third greater than 20 years ago, and that the threat from climate change now was so urgent that only very large cuts in greenhouse gases of 60 to 80 percent could stop irreversible change.