Despite both presidential candidates' belief that aggressive action is needed to reduce the country's carbon emissions, talk of climate change has amounted to a mere whisper in the final weeks of the campaign.
The immediate concerns of a lurching economy and the loss of jobs and retirement savings have drowned out nearly everything else. Barack Obama and John McCain have talked extensively about the country's energy challenges, and they frame the debate through the lens of energy security, jobs and lower prices.
Solutions that address reducing dependence on foreign oil don't necessarily lessen carbon emissions, which the vast majority of scientists believe are dangerously warming earth's climate.
Activists who want McCain and Obama to create the political will to reduce carbon emissions face a rigid political reality: the candidates need votes.
"Both campaigns certainly understand that the objective of reducing greenhouse gases is going to require more expensive energy in the short and medium run, and that's not what they want to campaign on," said Andy Keeler, an energy economist at the John Glenn School of Public Affairs at Ohio State University.
Votes are especially important in states such as Ohio and Pennsylvania, whose economies and electricity industries are heavily dependent on coal — a major source of carbon pollution.
The defining feature of both candidates' plans to address climate change is a cap-and-trade system, in which limits are placed on carbon emissions and companies have incentives to be cleaner than their competitors. Talk of cap-and-trade has largely been absent from recent campaign rhetoric, however.
A speech Wednesday in Ohio by McCain's vice presidential pick, Alaska Gov. Sarah Palin, contained only a couple brief mentions of greenhouse gases or climate change, and listed drilling and clean coal ahead of wind and solar technology in a list of ways to tackle energy problems. Palin has been skeptical of the consensus that climate change is largely a result of human activity.
The campaigns have sought to use clean-coal technology as a wedge issue. The technology refers to the ability to remove traditional pollutants from coal as well as capture and store the carbon emitted when it's burned. Obama's VP choice, Joe Biden, was recorded saying, "No coal plants here in America" at a campaign stop.
Palin then criticized Biden for the remark during the vice presidential debate, but Biden said his comments were taken out of context and that he and Obama support clean coal.
Climate change activists view clean coal as a distraction because many experts believe it is 10 to 20 years from being available for deployment on a full-scale, commercial level. Climate scientists have said the world must begin reducing carbon emissions immediately to prevent irreversible damage to glaciers, sea levels, climate patterns and species.
'Mixed bag' of answers
1Sky, an organization of youth climate activists, approached the candidates and recorded their responses to questions about climate change and creating green jobs. The candidates were often evasive on their answers, sometimes ignoring the questions or presenting clean coal as a major solution, said 1Sky organizer Carolyn Auwaerter.
"It's really been a mixed bag," said Auwaerter, who believes the candidates should be using their political power to educate the public about what must be done to combat climate change.
McCain spokesman Paul Lindsay acknowledged the economic downturn had taken precedence, but said McCain had stood up to fellow Republicans who were skeptics about climate change.
"Our nation's financial crisis has taken center-stage in this campaign, but John McCain is strongly committed to safeguarding the environment while strengthening our economy at the same time," Lindsay said.
Obama spokesman Isaac Baker said Obama's record and positions are clear.
"He is committed to combating climate change by investing in an array of clean and renewable energy technologies," Baker said.