Global Warming Is Fact, and Denial Won't Change Climate Back

Joseph Romm, a physicist, climate expert, and senior fellow at the Center for American Progress, blogs at ClimateProgress.org and is author of Straight Up and Hell and High Water.

Big Oil wants us to remain addicted to oil, a major source of carbon pollution. So it and other special interests have conducted an aggressive disinformation campaign for more than a decade to convince Americans that there's a major disagreement among scientists on the dangers posed by carbon pollution, just as the tobacco industry disputed the science to keep smokers addicted.

Yes, the 3,000-page review of the scientific literature by the United Nations' Intergovernmental Panel on Climate Change in 2007 has a couple of "trivial mistakes" in it, as the Washington Post put it. But as a physicist who writes on climate issues, I've read much of the original literature and talked to dozens of the leading climate scientists. The real story was captured in a recent headline in Scientific American: "Despite Climategate, IPCC Mostly Underestimates Climate Change."

The British Royal Academy, the oldest scientific body in the world, and the Met Office, part of the United Kingdom's Defense Ministry, noted that "even since the 2007 IPCC Assessment, the evidence for dangerous, long-term, and potentially irreversible climate change has strengthened."

The basic science is clear. Naturally occurring, heat-trapping gases keep the planet about 60 degrees warmer than it would otherwise be, giving us the livable climate we have today. Since the industrial revolution, humankind has spewed vast quantities of extra greenhouse gases, principally carbon dioxide from fossil fuels, into the atmosphere, causing more and more heat to be trapped. And so the atmosphere is warming. Deke Arndt, climate monitoring chief at the National Oceanic and Atmospheric Administration, said in October, "The last 10 years are the warmest 10-year period of the modern record." It may have seemed like a cool January in parts of this country, but globally it was the hottest January in the satellite record. And while it may be counterintuitive, we actually get more snowstorms in warm years.

The Bush administration concluded in a 2008 report, "It is well established ... that the global warming of the past 50 years is due primarily to human-induced increases in heat-trapping gases." That study noted that we're already seeing more extreme weather events.

In the past million years, the climate was primarily driven by natural cycles initiated by changes in Earth's orbit, which led to emissions of greenhouse gases, an amplifying feedback that caused rapid warming after long ice ages. As pre-eminent climatologist Wallace Broecker wrote in 1995, "The paleoclimate record shouts out to us that, far from being self-stabilizing, the Earth's climate system is an ornery beast which overreacts even to small nudges."

Now we are punching the beast in the face. If we don't act quickly, by midcentury carbon dioxide concentrations in the air will reach levels not seen in 15 million years, when it was 5 to 10 degrees warmer and seas were 75 to 120 feet higher, a 2009 study concluded.

The good news is that sea levels don't rise as fast as temperatures, but the bad news is that everywhere you look around the planet, ice is disappearing much faster than expected. Whereas the IPCC had ignored dynamic effects and predicted sea levels might rise perhaps only 1 to 2 feet in this century if we took no action to reduce emissions, major studies since 2007 put the estimate at 3 to 6 feet, enough to generate 100 million environmental refugees or more. Other studies warn that the U.S. Southwest could become a permanent dust bowl post-2040, with Kansas in the Midwest above 90 degrees some 120 days a year.

Republican Sen. Lindsey Graham said in January: "You'll never have energy independence until you clean up the air, and you'll never clean up the air until you price carbon."

We can preserve clean air and a livable climate for our children while slashing the $1 billion a day we send overseas to buy foreign oil and generating millions of good jobs in clean energy industries. But only if the bipartisan effort to pass a comprehensive climate bill led by Graham succeeds. It's time to blow away the smoke once and for all.

Read why the global warming "consensus" is no such thing, by Sen. James Inhofe.

• Check out our editorial cartoons on Global Warming.
• See our slideshow: 10 Winners from Obama's Green Jobs Incentives.