John Hickenlooper says the evidence he’s seen from scientists across the world pointing to climate change is “shocking.” “It’s pretty compelling,” Denver’s mayor tells 9News via telephone from Copenhagen, Denmark, where he is among the world leaders discussing myriad issues, including ways to address rising global pollution. “My takeaway is I want to come back to Denver and sit down with every skeptic I can find and just walk them through all the evidence.” Hick is thinking of city planning in a new light, emphasizing “little villages” that don’t cause so much waste and focus on quality of life. “When you’re planning and building a city, you can’t do it for next year or for the next five years,” he says. “What you’ve got to be thinking about is your children’s grandchildren, and it’s a different way of thinking than a lot of Americans are used to.” Hickenlooper even appeared on Democracy Now! to discuss the issues.

Meanwhile, negotiators at the climate talks have their work cut out for them. If they are to reach an accord, there would have to be profound shifts in energy production, for instance, in a variety of programs and measures that would cost “trillions of dollars” over the coming decades, according to The New York Times, which calls the sum significant but a small fraction of the world’s economic output. Still, there are skeptics who don’t believe pollution is really causing undesirable climate change. University of Colorado Earth Science and Observation Center director Waleed Abdalati tells The Denver Post, after a presentation to delegates in Copenhagen, “There seems to be a sense that perhaps we are acting too late,” pointing to maps of lost ice. “People can quarrel about whether temperature has changed 1 degree or 1.5 degrees in the last so many years, but the presence or absence of ice is very tangible, as is the idea of oceans rising and inundating coastal areas.”