As recently as 2008, presidential candidates openly sparred over their own plans for dealing with climate change. This year it's such a touchy topic that both sides prefer instead to talk about energy policy – a kind of proxy for climate threat.
Here are four ways the candidates differ on climate change: Is climate change a problem caused by humans? Should the US adopt market-based approaches to curbing greenhouse gases? Has the Environmental Protection Agency gone too far? Is the Obama administration waging a "war on coal"?
Although they were once close at least in recognizing climate change as a problem – and in seeking a market-based approach to curbing plant emissions – President Obama and Republican nominee Mitt Romney now come at the issue from sharply different perspectives.
In his 2010 book, "No Apology: The Case for American Greatness," former Massachusetts Governor Romney said that he believed that climate change is occurring, and that humans have a role in causing it. "The reduction in the size of global ice caps is hard to ignore." At a June 3, 2011, town meeting in Manchester, N.H., he said: "I believe based on what I read that the world is getting warmer.... and that humans contribute to that."
But responding to a question in Pittsburgh just four months later, Romney said: "My view is that we don't know what's causing climate change on this planet. And the idea of spending trillions and trillions of dollars to try to reduce CO2 emissions is not the right course for us."
In contrast, Mr. Obama told world leaders at a UN summit on climate change in 2009 that "the security and stability of each nation and all peoples – our prosperity, our health, and our safety – are in jeopardy." He added: "And the time we have to reverse this tide is running out.”
Obama has held the position that climate change is caused by humans, especially by fossil energy burning, since at least his time in the US Senate, when he and 39 other senators in 2006 wrote President Bush calling for government-imposed limits on heat-trapping gas emissions. Obama in January 2007 joined Sen. John McCain (R) of Arizona in co-sponsoring a major climate change bill. He also pledged to mobilize an international coalition to help curb carbon emissions.
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