...The nations of the world are meeting here to hash out a "rulebook" to help ensure the viability of humanity -- preventing runaway global warming from causing even greater calamity in the form of superstorms, searing droughts and deadly heat waves.

That work, which follows up on the 2015 Paris Agreement, is seen as more critical now than ever. A damning report from the United Nations this fall said there's only about a decade left to avoid the worst of climate change. The message: cut fossil fuel pollution to "net zero" in just a few decades.

Yet the United States held a discussion on Monday that was meant, among other things, to "showcase ways to use fossil fuels as cleanly and efficiently as possible."

Vic Barrett, a 19-year-old college student in Wisconsin, was among those who decided that was too much to take. She and dozens of other protestors erupted in mock laughter as Preston Wells Griffith, an official at the US Department of Energy, spoke about how fossil fuels "will continue to play a role" in the global energy picture. They temporarily stopped the US-led discussion, shouting, "shame on you!" and "keep it in the ground!" -- a reference to fossil fuels that they say should be left unearthed.