NEW YORK - Maybe it's the weird winter weather, or the newly Democratic Congress. Maybe it's the news reports about starving polar bears, or the Oscar nomination for Al Gore's global warming cri de coeur, "An Inconvenient Truth." Whatever the reason, years of resistance to the reality of climate change are suddenly melting away like the soon-to-be-history snows of Kilimanjaro.
Now even George W. Bush says it's a problem.
For years, the president and his supporters argued that not enough was known about global warming to do anything about it. But during last week's State of the Union address Bush finally referred to global warming as an established fact.
"These technologies will help us be better stewards of the environment, and they will help us to confront the serious challenge of global climate change," Bush said in proposing a series of measures to reduce gasoline consumption by 20 percent in 10 years.
Environmentalists and scientists who study the problem say the nostrums Bush proposed Tuesday night will do little to prevent the serious environmental effects that the globe faces in coming decades.
Environmentalists favor imposing a mandatory cap on greenhouse gas emissions tied to a market-based emissions trading system. Several of the global warming bills that have been introduced to the new Democrat-controlled Congress would do exactly that. House Speaker Nancy Pelosi (news, bio, voting record) has proposed creating a new global warming committee to consider the legislation.
"We want the pressure on. The pressure will drive the development of new technologies," said Rep. Henry Waxman (news, bio, voting record), D-Calif., who introduced one of the global warming bills.
Many industry leaders have come to realize that such measures may be more an opportunity than a hindrance. The day before Bush's speech the chief executives of 10 corporations, including Alcoa Inc., BP America Inc., DuPont Co., Caterpillar Inc., General Electric Co. and Duke Energy Corp., called for mandatory limits on greenhouse gas emissions.
"It must be mandatory, so there is no doubt about our actions," said Jim Rogers, chairman of Duke Energy. "The science of global warming is clear. We know enough to act now. We must act now."
And a week before the State of the Union address a dozen evangelicals called action against global warming a "moral imperative" in a joint statement with scientists from the Centers for Disease Control, NASA, Harvard and other institutions.
There is still plenty of opposition to action on global warming in both the evangelical and business communities, but the tide is clearly turning.
"You're seeing a major political shift that is fairly broad-based," said Robert Watson, a scientist at the World Bank and former chairman of the United Nations scientific panel responsible for evaluating the threat of climate change.
Scientists have been at the vanguard of the climate change issue for decades. As early as 1965 a scientific advisory board to President Johnson warned that increasing atmospheric carbon dioxide could lead to "marked changes in climate" by 2000.
In 1988 the United Nations created the Intergovernmental Panel on Climate Change. Though assailed by critics as an overly alarmist organization, the panel actually represents a relatively cautious assessment of global warming because it relies on input from hundreds of scientists, including well-known skeptics and industry researchers.
Every five or six years since 1990, the IPCC has released an updated assessment of the environmental threat posed by global warming. And every time, a single memorable and increasingly alarming statement has stood out from the thousands of pages of technical discussion.
The first report noted that Earth's average temperature had risen by 0.5 to one degree Fahrenheit in the past century, a warming consistent with the global warming predictions but still within the range of natural climate variability.
"The observed increase could be largely due to this natural variability," the scientists concluded.
But by 1995 that possibility had all but vanished: "The balance of evidence suggests a discernable human influence on global climate," the second IPCC report concluded.
Six years after that: "There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities."
Since then, scientists have accumulated abundant evidence that global warming is upon us. They have documented a dramatic retreat of the Arctic sea in recent summers, accelerated melting on the Greenland and Antarctic ice caps and the virtual collapse in mountain glaciers around the globe. They have found plants and animals well poleward of their normal ranges. They have recorded temperature records in many locations and shifts in atmospheric and oceanic circulation. Globally, the planet is the warmest it has been in thousands of years, if not more.
Emboldened by these discoveries, scientists just in the last month have issued some dire warnings. The Bulletin of Atomic Scientists, originally formed in response to the dangers of nuclear weapons, cited the climate change threat in moving its "doomsday clock" two minutes closer to midnight. And Britain's meteorological agency announced just three days into the year that 2007 has a 60 percent likelihood of being the warmest year on record, thanks to the combined effects of global warming and El Nino.
"You just can't explain the observed changes that we've seen in the last half of the 20th century by invoking natural causes," said Benjamin Santer, a U.S. government scientist who was involved in previous IPCC assessments.
The scientists who will gather in Paris this coming week to complete the first section of this year's IPCC report are not allowed to talk about the early drafts that have been circulating in recent months.
But there is little doubt that when the report is released on Friday it will include references to some of the specific environmental effects of global warming that have already been observed, and an even stronger statement about the imminent threat of global warming.
