Left, President Obama plays golf in Martha’s Vineyard. (Susan Walsh/AP) Right, Bear Grylls in “Get Out Alive with Bear Grylls.” (Jasin Boland/NBC)

As far as hiking buddies go, Barack Obama and Bear Grylls make for an unlikely pairing. Grylls is a TV outdoorsman with a flair for drama and a propensity for drinking his own urine. Obama is cerebral and stolidly even-keeled, and, you know, the president of the United States.

Nevertheless, the strange duo is slated for some bonding Tuesday while hiking the Exit Glacier, a south Alaskan river of ice that has shrunk by 1.25 miles in recent decades. They have no plans to drink urine, Grylls has confirmed, and the adventurer’s usually madcap exploits will be scaled down to “interesting,” in the words of White House press secretary Josh Earnest.

Instead, they’ll talk climate change while testing Obama’s survival skills under the watchful eye of the Secret Service. The whole trip will be taped and will air on Grylls’s NBC show “Running Wild” later this year.

Bear Grylls begins his descent off a cliff in Whakatane, located about 200 miles north of Auckland in New Zealand, on March 1, 2011. (Luis Enrique Ascuti/ Getty Images)

[Obama takes a turn at reality TV in Alaska]

Coming amid a three-day trip to Alaska aimed at promoting his environmental agenda, Obama’s hike with Grylls is an unorthodox new tactic. If reasoned argument, moralist appeals and dire predictions of impending disaster aren’t enough to draw people’s attention to climate change, perhaps a jaunt through the wilderness for reality TV will.

In that effort, Grylls is an ideal partner. The 41-year-old British daredevil has made a living out of being so outrageous you can’t help but pay attention. His television programs play like a cross between “Survivor” and “Fear Factor,” but without the million dollar prize at the end. Grylls doesn’t need a cash reward to persuade him to sip on water squeezed from elephant dung, subsist on a diet of bugs or risk his life para-motoring past Mount Everest (though with nine TV shows to his name, he certainly doesn’t lack for money). He does it for fun.

“I’ve got a dream job,” he told Outside magazine in 2010, while taping his series “Worst Case Scenario.” “… I feel like I’ve been doing this since I was five years old. If someone had told me then, when I was climbing trees and caked in mud, that one day I’ll have a job doing the exact same thing, I would have thought it was heaven.”

Deion Sanders and Bear Grylls in “Running Wild with Bear Grylls.” (Duncan Gaudin/NBC)

[Obama using Alaska to add urgency to his climate change warnings]

Grylls grew up in the U.K., the son of Conservative member of parliament Sir Michael Grylls. According to Outside, his sister gave him the nickname Bear. (“I was a bossy big sister, and he was my toy,” she told the magazine. “I was always getting him to do things.”)

Partway through university, he joined the United Kingdom Special Forces Reserve and nearly died during a training parachute jump in Africa. During his 18-month recovery, he vowed that if he walked again he would climb Mount Everest, according to Men’s Journal. He finally did in 1998, becoming at age 23 one of the youngest Brits to reach the world’s tallest peak.

The climb turned out to be the more conventional of the feats that would soon clog Grylls’s resume. In the past two decades, he has become the first person to circumnavigate the U.K. on a jet ski and the first to cross the North Atlantic in an open inflatable boat. He took part in the world’s highest open-air dinner party (dangling from a hot air balloon at 25,000 feet, the guests had to wear gas masks or risk deadly hypoxia), and he has set a Guinness world record for longest indoor free-fall. A passionate defender of the environment, Grylls has dedicated a number of his adventures to raising money for the sustainable development organization Global Angels and for climate change awareness groups.

His TV exploits have brought controversy. In 2007, it was revealed that parts of “Man vs. Wild” were scouted and orchestrated — wild animals were sometimes removed from cages and placed in Grylls’s path; treks were filmed not on remote islands but near comfortable hotels. In response, Discovery added a disclaimer to the beginning of the program: “On some occasions, situations are presented to Bear so he can demonstrate survival techniques,” it read.

Grylls’s survival skills series “The Island” has likewise been accused of “fakery” and has gotten flak from female adventurers and animal rights activists for initially excluding women and featuring the killing of animals. But the fracas doesn’t seem to have hurt Grylls’s shows, which still get several million viewers a week.

The truth is that Grylls, like all reality TV stars, benefits from a little drama. He has less in common with Sir David Attenborough than he does with Kim Kardashian.

But that might be exactly what Obama is looking for. After all, he’s already met with Attenborough, in an interview at the White House this June that focused on the environment and climate change. The BBC called the meeting “an extraordinary meeting of minds.” Obama’s hike with Grylls seems unlikely to be described in the same language.

What it might be is a compelling P.R. opportunity for a president hoping to focus on the climate while avoiding conflict over Arctic oil drilling and management of the area’s natural wealth.

An appearance on “Running Wild,” which has also hosted Zac Efron, Deion Sanders and Kate Winslet, seems like a good attention grabber. After all, the Alaskan wilderness — framed by blue-gray mountains and glowing ice — is a dramatic stage, and Grylls is an expert entertainer.

Now if only Grylls can persuade Obama to eat a few bugs. You know, for the environment.