Desperate times, desperate scientists

Dec. 12, 2007 | How dire is the climate situation? Consider what Rajendra Pachauri, the head of the United Nations' prestigious Intergovernmental Panel on Climate Change (IPCC), said last month: "If there's no action before 2012, that's too late. What we do in the next two to three years will determine our future. This is the defining moment." Pachauri has the distinction, or misfortune, of being both an engineer and an economist, two professions not known for overheated rhetoric.

In fact, far from being an alarmist, Pachauri was specifically chosen as IPCC chair in 2002 after the Bush administration waged a successful campaign to have him replace the outspoken Dr. Robert Watson, who was opposed by fossil fuel companies like ExxonMobil. So why is a normally low-key scientist getting more desperate in his efforts to spur the planet to action?

Part of the answer is the most recent IPCC assessment report. For the first time in six years, more than 2,000 of the world's top scientists reviewed and synthesized all of the scientific knowledge about global warming. The Fourth Assessment Report makes clear that the accelerating emissions of human-generated heat-trapping gases has brought the planet close to crossing a threshold that will lead to irreversible catastrophe. Yet like Cassandra's warning about the Trojan horse, the IPCC report has fallen on deaf ears, especially those of conservative politicians, even as its findings are the most grave to date.

Part of this is due to the IPCC's own media naiveté. It doesn't put a lot of thought into publicizing its reports; heck, it released this final synthesis on Nov. 17 -- a Saturday! -- in Valencia, Spain. Not exactly the best way to get attention from the most intransigent and important audience: Americans. How little attention? According to Technorati.com, as of Dec. 11, the synthesis report had some 265 blog reactions, where the Aug. 24 YouTube video of Miss Teen South Carolina struggling to explain why a fifth of Americans can't locate the U.S. on a world map had more than 5,300 blog reactions. Hmmm. Perhaps these two things are related. But I digress.

With such poor notice for a seminal document, more than 200 scientists last week took the remarkable step of issuing a plea at the United Nations climate change conference in Bali. Global greenhouse gas emissions, they declared, "must peak and decline in the next 10 to 15 years, so there is no time to lose." The Associated Press headline on the statement was "Scientists Beg for Climate Action." What will we drive climate scientists to next? A hunger strike?

Since many if not most people mistakenly think that other countries are going to suffer much worse than ours, let me focus on the three impacts that most directly threaten this country. The first is sea level rise. The IPCC consensus synthesis report from last month warned:

"Anthropogenic warming could lead to some impacts that are abrupt or irreversible, depending upon the rate and magnitude of the climate change. Partial loss of ice sheets on polar land could imply [tens of feet] of sea level rise, major changes in coastlines and inundation of low-lying areas, with greatest effects in river deltas and low-lying islands. Such changes are projected to occur over millennial time scales, but more rapid sea level rise on century time scales cannot be excluded."

The oceans may take centuries to rise 40 to 80 feet, but that rise may be irreversible as early as the second half of this century. Also, many people seem to think scientists are warning about a one-time sea level rise, say a few feet, which would be painful, but still fairly straightforward to adapt to. In fact, we are potentially talking about sea level rise of 6 to 12 inches a decade by century's end, with that rate continuing for centuries. It's not at all clear how future generations would adapt to such an ongoing catastrophe.

The likely rate of future sea level is not known precisely because we have no good models for the kind of abrupt ice loss we are seeing now, especially in Greenland and West Antarctica. The next IPCC assessment will probably have projections from a number of such models. For a nation with so much wealth and population on the coasts, waiting for more precision on the pace and scale of sea level rise would be suicidal.

The second big direct threat to this country is drought. The IPCC report concludes there is a better than two-thirds chance the planet has already seen an increase in drought-stricken areas since the 1970s. And there's a better than 80 percent chance that many semi-arid areas, including the Western United States, southern Africa and northeast Brazil, will suffer a decrease in water resources due to climate change. Australia recently abandoned its anti-Kyoto political leadership in large part because of a brutal once-in-a-thousand-years drought affecting most of the country, which Australian scientists link to climate change.

The United States has recently been experiencing some of its worst droughts in history, including in the Southeast and Southern California, which has helped drive record wildfires in this country. Regional climate modeling remains a difficult art. Yet the Bush administration has for seven years worked hard to conceal from the public all research on an assessment of U.S. climate impacts. First, it undercut all efforts to publicize the first national assessment finished in 2000, and then, as science writer Chris Mooney put it, replaced "a required follow-up assessment with what amounted to a scientific sham."

A study in the April issue of Science, too recent to be part of the recent IPCC review, "predicted a permanent drought by 2050 throughout the Southwest" if we don't reverse emissions trends. We could wait for the next IPCC assessment for more detail, or wait for a new president to launch a multiyear assessment of U.S. impacts. But with the already arid and drought-stricken West experiencing record population growth, further inaction leaves open the possibility that tens of millions of Americans will be living in an enormous Dust Bowl.

Next page: The IPCC has reached the end of its usefulness