His message is as terrifying as ever. Anthropogenic climate change is already producing massive sea temperature changes, huge storms, rising water levels, and climate refugees, Gore says.

He likens the “mass delusion” that now exists in fossil-fuel markets—the value of which are based on the premise that those fuels can be burned without consequence—to America’s sub-prime mortgage crisis, only worse. There exists $22 trillion dollars of “book market capital” in fossil fuels that cannot be burned if we’re to avoid complete destruction of the environment, he says. This is based on ”an assumption even more absurd” than what led to 2008’s global financial meltdown, he adds.

And yet, only minutes before the end of his presentation, Gore says he is optimistic.

“There’s exciting news,” he says. And that, it turns out, is the enormous increase in renewable-energy technology and generation capacity. The costs of mature renewable technologies like wind and solar are plummeting, he says. Last year, 90% of all new energy capacity built was renewable, according to the International Energy Agency.

“You talk about an exponential curve? This one is taking off like a skyrocket,” Gore says, pointing to a chart showing global solar photovoltaic installation from 1980 to 2015.

Gore points to his "skyrocket" solar chart.
Gore points to his “skyrocket” solar chart.
Image: Skoll World Forum/YouTube

What’s more: “The battery market is booming, and it is poised for a massive period of growth,” he says, which will address the problems of storing the intermittent power that wind and solar produces.

Gore likens the shift to greener energy to the advent of the mobile phone—a technology which not only revolutionized how we communicate, but also allowed societies without fixed-line networks to “leapfrog” directly to mobiles. In the same way, he explained, societies that have never had a power grid are eschewing centralized generation for distributed renewable networks.

Gore asks three questions through his talk: Do we have to change, can we change, and will we change? And, a master of rhetoric, he quotes Wallace Stevens to answer them:

“After the final no there comes a yes
And on that yes the future world depends.”

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