‘Years of Living Dangerously': David Letterman, Cecily Strong Save the Earth (Exclusive Videos)

Watch former “Late Show” host’s self-diagnosed “pessimism” diminish before your very eyes

The planet needs a hero. What it’s got is David Letterman and Cecily Strong. Good enough? Let’s hope so.

Those two have loaned their faces and celebrity to one of the more crucial causes we currently face — the effort to press pause on (and even hopefully reverse some) climate change. Such is the mission of National Geographic Channel’s ambitious “Years of Living Dangerously.”

In a clip from the former “Late Show” host’s turn, one which is exclusive to TheWrap, Letterman tours an Indian solar field with government officials. What the curmudgeonly comedian observes forces a rare smile just above his mangy beard.

“I see this and my pessimism diminishes,” Letterman says. Watch that video above.

For her episode, “Saturday Night Live” star Cecily Strong tries to figure out exactly who is blocking the sun in America. Yes, who.

Solar power seems like the perfect (and obvious) solution to Nevada’s own energy issues, for one example. Because, you know, it’s a desert. And that’s where she is, attempting to uncover what on Earth is stopping us from saving the Earth.

“Energy worldwide is a $6 trillion a year business, and the first goal of the people in that industry is to make sure it continues to be a $6 trillion a year business,” one former oil exec admits to the “SNL” player. Fabulous.

The other Season 2 celebrity correspondents are: Jack Black, Gisele Bündchen, Ty Burrell, Don Cheadle, America Ferrera, Thomas Friedman, Joshua Jackson, Aasif Mandvi, Nikki Reed, executive producer Arnold Schwarzenegger, Ian Somerhalder, Sigourney Weaver and Bradley Whitford.

James Cameron and the late Jerry Weintraub also executive produce the series, along with “60 Minutes” producers Joel Bach and David Gelber, and climate expert Daniel Abbasi. “Years of Living Dangerously” won the 2014 Emmy award for Outstanding Documentary or Nonfiction Series.

Here’s Strong, from the restricted rooftop at Mandalay Bay:

Season 2 of “Years of Living Dangerously” premieres Sunday, Oct. 30 at 8/7c on National Geographic Channel.

The series will move to its regularly scheduled time –Wednesdays at 10/9c — beginning Nov. 2. The sophomore run will air on NGC in 171 countries and 45 languages.

As part of its effort to bail us all out, Nat Geo is also premiering Leonardo DiCaprio’s climate change documentary “Before the Flood” on Sunday. Click here to learn more from our interview with channel CEO Courteney Monroe.