Wednesday, June 28, 2006

This is NOT the worst-case scenario


These images are from the July 13 issue of The New York Review of Books. On the left is Florida as seen from space today. On the right is what’s left of Florida after a sea level rise of only 18-20 feet. Again, this is not a worst-case global warming scenario.

The photos are provided by NASA’s chief climate scientist Jim Hansen, whose essay in the current issue delivers a powerful warning, “The Threat to the Planet.” Hansen’s article is prefaced with an unusual note for a government scientist:
His opinions are expressed here, he writes, "as personal views under the protection of the First Amendment of the United States Constitution."
That’s a reference to the contretemps about the Bush administration’s ham-handed attempts to muzzle him earlier this year -- and the constitutional protection that still allows him the freedom to speak out, despite the administration's best efforts to silence him.

THIS is the worst-case scenario
If we continue on our current business-as-usual course, according to Hansen, there will be a five-degree Fahrenheit increase in global warming by the end of the century, resulting in an 80-foot increase in sea level, which would doom almost all of Florida and a whole lot more.
How much will sea level rise with five degrees of global warming? Here too, our best information comes from the Earth's history. The last time that the Earth was five degrees warmer was three million years ago, when sea level was about eighty feet higher.

Eighty feet! In that case, the United States would lose most East Coast cities: Boston, New York, Philadelphia, Washington, and Miami; indeed, practically the entire state of Florida would be under water. Fifty million people in the US live below that sea level. Other places would fare worse. China would have 250 million displaced persons. Bangladesh would produce 120 million refugees, practically the entire nation. India would lose the land of 150 million people.
But that’s a future that may yet be averted. Meanwhile, global warming is real today and already having significant impacts, as Hansen movingly relates in the opening of his essay.
Animals are on the run. Plants are migrating too. The Earth's creatures, save for one species, do not have thermostats in their living rooms that they can adjust for an optimum environment. Animals and plants are adapted to specific climate zones, and they can survive only when they are in those zones. Indeed, scientists often define climate zones by the vegetation and animal life that they support. Gardeners and bird watchers are well aware of this, and their handbooks contain maps of the zones in which a tree or flower can survive and the range of each bird species.
The question is, will the one species that has the ability to adjust the thermostat have the insight and the political will to do so before it’s too late? That’s what the works reviewed by Hansen are about.
“The Weather Makers: How Man Is Changing the Climate and What It Means for Life on Earth,” by Tim Flannery, Atlantic Monthly Press, 357 pp., $24.00

“Field Notes from a Catastrophe: Man, Nature, and Climate Change,” by Elizabeth Kolbert, Bloomsbury, 210 pp., $22.95

“An Inconvenient Truth: The Planetary Emergency of Global Warming and What We Can Do About It,” by Al Gore, Melcher Media/Rodale, 325 pp., $21.95 (paper)

“An Inconvenient Truth,” a film directed by Davis Guggenheim
Hansen has special praise for Gore and puts him in some pretty good company.
Indeed, Gore was prescient. For decades he has maintained that the Earth was teetering in the balance, even when doing so subjected him to ridicule from other politicians and cost him votes. By telling the story of climate change with striking clarity in both his book and movie, Al Gore may have done for global warming what Silent Spring did for pesticides. He will be attacked, but the public will have the information needed to distinguish our long-term well being from short-term special interests.

“An Inconvenient Truth” is about Gore himself as well as global warming. It shows the man that I met in the 1980s at scientific roundtable discussions, passionate and knowledgeable, true to the message he has delivered for years. It makes one wonder whether the American public has not been deceived by the distorted images of him that have been presented by the press and television. Perhaps the country came close to having the leadership it needed to deal with a grave threat to the planet, but did not realize it.
“An Inconvenient Truth” is playing at a multiplex near you. Go see it -- while the theater is still above water.

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