Al Gore's "Inconvenient Truth" has been listed among the top 10 eco-disaster movies of all time. But while it awakened many people to the threat of climate change, others were disappointed that it focused more on the problem, less on the solutions. Nowadays, however, Al Gore appears decidedly upbeat.

In a recent New York Times piece on the new optimism of Al Gore, the former vice president attributes this change of heart to the unexpected and unprecedented rate at which the world is decarbonizing and investing in alternatives: 

Investment in renewable energy sources like wind and solar is skyrocketing as their costs plummet. He has slides for that, too. Experts predicted in 2000 that wind generated power worldwide would reach 30 gigawatts; by 2010, it was 200 gigawatts, and by last year it reached nearly 370, or more than 12 times higher. Installations of solar power would add one new gigawatt per year by 2010, predictions in 2002 stated. It turned out to be 17 times that by 2010 and 48 times that amount last year.
Comparing the disparity in clean energy projections to the roll out of cellphones, Gore points out that in 1980, analysts predicted that the market for cellphones would reach 900,000 units sold by 2000. The actual figure turned out to be 109 million.

Chinese coal production is falling years ahead of predictions. Solar is booming in emerging markets like Latin America, sometimes without subsidies. Corporations are reaching carbon reduction goals years ahead of schedule. Entire cities are gunning for 100 percent renewable energy. This shift in Gore's perspective is one more sign that in boardrooms, government halls and the mass media, the conversation about climate change is shifting from whether or not it's happening to how (and how fast) we can transition to a low-carbon economy. (Sadly, this shift has not yet made it to the comments section of blogs like these.)

In terms of supporting solutions, Gore has helped to move things forward while earning a healthy return too — investing heavily in clean energy ventures and companies that put sustainability at the center of their business practices. While critics have accused him of profiting from the crisis, Gore defends his approach, suggesting that doing anything else would make him a hypocrite:

Is participating in the green economy a conflict of interest? “I think that having a consistent outlook in my advocacy and in the way I invest is a healthy way to live,” he says. Much of what he makes, including all salary from his early stage investing work as a partner at Kleiner Perkins and his Nobel Prize money, goes to his advocacy group, the Climate Reality Project. “I never imagined when I was younger that this would become the principal focus of my life,” he says. “But once you pick up this challenge, you can’t put it down. I can’t. Don’t want to.” 
With some of the biggest players in our economy going all out for renewables, and even traditional energy-intensive companies like Dow Chemical betting heavily on wind power, it's easy to see why Gore might be feeling optimistic. And he emphasizes that optimism with a confident prediction: 

“We’re going to win this.” He pauses and repeats for effect, part preacher and part TED talk. “We’re going to win this. The only question is how long it takes.

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