Eric Larsen and Ryan Waters spent two months trekking across the Arctic to reach the North Pole, before climate change makes it an impossible journey. (Eric Larsen)

With the Arctic melting and possibly disappearing forever, decided to return to the North Pole, despite having gone twice before. Larsen describes this journey as “one of the most difficult expeditions on the planet,” but found it necessary to go.

“Realistically, this type of expedition will not be possible in the future, and that is a sad thing to know you may be the last [explorer],” Larsen told weather.com. “I wanted to tell the story of this unique place and how it is changing.”

The 500-mile journey from Ellesmere Island in Nunavut, Canada to the North Pole took Larsen and his expedition partner, Ryan Waters, two months to finish. Along the way, they pulled through with lightweight sleds that carried more than 320 pounds of food, fuel and equipment—an unsupported journey.

This isn’t a trip to be taken lightly. Larsen and Waters planned and trained for over a year in preparation of the expedition. Though the pair wanted to add one more person to the team, they couldn’t find someone willing to commit to the expedition. With Waters’ prior experience skiing unsupported across Antarctica and several summits to Mount Everest, they decided to embark on the expedition by themselves.

The Arctic Ocean is and also the. Physically pulling supplies with skis or snowshoes on, while enduring extreme conditions, is an exhausting feat. “We are traveling in a very narrow margin of safety and have to be constantly vigilant,” Larsen said.

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Melting and drifting ice conditions made the journey difficult for the two explorers. “For the first three weeks of the journey, we averaged roughly three miles a day,” he said. Their average would, at times, decrease as they ended up drifting backwards on the moving ice during their sleep.

Covering distance wasn’t the only difficulty. “We had a very close call with two polar bears that were stalking us,” Larsen said. Waters also fell through the ice up to his chest and the two of them almost ran out of food and fuel. Their diminishing supplies were also endangered to the frigid weather conditions.

“At 30 or 40 degrees below zero, nylon can tear like a sheet of paper and tent poles can snap like a dry twig,” Larsen said. “A huge part of our preparation was simply training and testing equipment.” One of their most valued items was a DeLorme inReach, a two-way satellite communicator, tracking device and SOS trigger. Other important supplies include snowshoes with great traction for the ice and snow as well as base layers that wick sweat away while retaining enough body heat. “Surprisingly, however, at 30 or 40 below zero, I am often more concerned about getting too warm than too cold,” Larsen said.

At the end of the day, Larsen valued his sleep the most. “It meant a short reprieve from the pain and hardship we were constantly during,” he said. “Still, spending that much time, day after day, traveling across the ice—human powered—gives you a better understanding of [the] environment. The ice is incredible and beautiful. Even though we felt at times the Arctic Ocean was trying to kill us, this was a once-in-a-lifetime opportunity.”

When Larsen returned home, the first thing he did was hug his wife and son. But of course, a man that takes a challenging expedition to the North Pole can’t stay home for too long. He is currently planning bigger expeditions to Mongolia and Nepal.

For a more detailed look into Larsen’s expedition, you can find the details in his recently published book, On Thin Ice: An Epic Final Quest into the Melting Arctic.

To follow along Larsen’s future journeys, find him on and .