At a debate in North Carolina in October 2000, Vice President Al Gore and Gov. George Bush were asked about their positions on global warming. Would they be willing to pass new regulations and laws to protect the environment? "Sure, absolutely," Bush replied, "so long as they're based on science and they're reasonable." But taking immediate action on climate change, however, he felt would be premature. "I don't think we've got all the facts," he said.
Eight years later, the facts on climate change are well known. Over the past 35 years, demand for energy has more than doubled. Fossil fuels—coal and oil, mainly—have powered the explosive growth, but their use has raised carbon dioxide levels in the atmosphere by more than 35 percent from preindustrial levels. As a result, the sun's rays no longer escape as easily from the atmosphere; some of their heat is radiated back, returning to the ground and the ocean, fueling global warming. In the next 40 years, average global temperatures are expected to rise by about 2 degrees Fahrenheit, causing profound disruptions in rainfall patterns, agriculture, wildlife, and human activity.
Now that there is consensus that global climate change is happening, the real debate is how the next president will address it. Several recent developments, including record oil prices, rapidly rising energy demand, and a growing awareness of the impact of fossil fuel use on the Earth, have provided ample evidence that energy and environment challenges are intimately connected and require a coordinated response. Voters, meanwhile, are growing more concerned. In June, a Gallup Poll found that 9 out of 10 voters say that high energy costs will influence their vote in November.
Sens. Barack Obama and John McCain have heeded the mounting concerns with a flurry of ambitious proposals and promises in recent weeks. McCain frequently argues that energy security is closely intertwined with "national security," if not a prerequisite for it. His campaign has dubbed Obama "Dr. No," a nickname his advisers say captures Obama's resistance to a host of potentially beneficial energy ideas, including nuclear energy. Obama has responded by comparing the presumptive Republican nominee to President Bush, citing their now shared support for offshore drilling.
Ambitious plans. Behind the rhetoric, genuine distinctions emerge, although on the question of cutting greenhouse gas emissions—widely considered the most pressing environmental challenge of the moment—the candidates' views are broadly similar. Both support mandatory federal emissions limits. They agree in principle that reductions should be pursued through cap-and-trade systems, under which the government would set a limit on the total amount of greenhouse gases businesses could emit, and bigger polluters would have to buy emissions allowances from cleaner companies. Obama's proposal goes further than McCain's, requiring that the United States cut carbon dioxide emissions 80 percent from the 1990 levels by 2050; McCain would require only a 60 percent reduction, and distribute some of the allowances to polluters for free. Both plans, nevertheless, are more ambitious than what world leaders have so far embraced. At last week's G-8 summit in Japan, officials reached a "historic" agreement for a 50 percent emissions cut by 2050.
Neither candidate's plan would pass Congress without a fight. Until recently, the Bush administration vigorously opposed even the idea of government-mandated emissions reductions, and leaders in the Republican Party continue to warn that stringent emissions caps could drain the economy of trillions of dollars. "They're both too much," Heritage Foundation senior policy analyst David Kreutzer says of the candidates' proposals. "In the Democratic primaries, it seems like there was a game of who can trump the other person. When you get to the environment, it's, 'Who is going to propose the greatest cut?'"
Many researchers and environmentalists, however, say that McCain, after years of leading on climate change issues, has failed to keep pace with new data and that only Obama's plan offers an adequate response. "McCain is still proposing the same levels [of emissions reductions] he was proposing in 2003, even though the science has advanced a lot," says Tony Massaro, political director of the League of Conservation Voters. "We now need more significant reductions because we've already seen things that weren't anticipated in 2003, such as massive ice sheet melting in Greenland." In the group's eyes, McCain's voting record has also lagged. In 2007, he missed every major vote on environmental legislation. McCain's lifetime score for voting "correctly" on environmental issues, according to the league's tally, is 24 percent; Obama's score, over a much shorter time period, is 86 percent.