Pope Francis greets mayors and governors in the Synod Hall during a conference on Modern Slavery and Climate Change at the Vatican last week. Boulder Mayor Matt Appelbaum is pictured near the top, in the left-hand corner. 

(AP Photo/L'Ossservatore Romano)

Pope Francis asked several dozen mayors and governors from around the world at the Vatican last week to take a "very strong stand" against climate change. Boulder Mayor Matt Appelbaum was there to add his signature to a declaration calling climate change a "scientific reality" that, if not challenged soon, will exacerbate poverty.

"Climate-change mitigation will require a rapid transformation to a world powered by renewable and other low-carbon energy and the sustainable management of ecosystems," the declaration states. "These transformations should be carried out in the context of globally agreed Sustainable Development Goals, consistent with ending extreme poverty; ensuring universal access to healthcare, quality education, safe water, and sustainable energy; and cooperating to end human trafficking and all forms of modern slavery."

The declaration calls for action at the United Nations climate talks later this year in Paris. "High-income countries," it states, "should help to finance the costs of climate-change mitigation in low-income countries as the high-income countries have promised to do."

A Quinnipiac poll last week indicates 62 percent of Coloradans agree with Pope Francis' call on the world to do more about climate change. Yet while 93 percent of of Colorado Democrats polled agree with the idea, just 38 percent of Republicans do.

Appelbaum, a Democrat, was among a handful of American representatives to attend. New York City Mayor Bill de Blasio and California Gov. Jerry Brown, both Democrats, also went, but no Republican mayors accepted invitations, according to U.S. News & World Report

Appelbaum spoke with Colorado Matters host Ryan Warner.

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