Having just come out of one of the hottest summers on record, wrought with droughts and wildfires, it’s a wonder that “climate change” doesn’t seem to exist in either of our 2012 presidential candidates’ vocabularies. Author and activist Bill McKibben notes that we can’t stop global warming, as the earth’s temperature has already risen, but “we can keep it from getting worse.”

—Steven Hsieh

Video filmed and edited by Karen Rybold-Chin.