'A voice in the wilderness': The man who spent 12 gruelling days swimming in the Arctic

Lewis Pugh has been swimming against the tide for 35 years.

He has swum in some of the world's most extreme waters, from the North Pole to Antarctica, to raise awareness of the impact humans are having on Earth and the effects of climate change.

His latest endeavour saw him spend 12 days completing the 'coldest swim on Earth' across the Ilulissat Icefjord in Greenland, which is fed by the world's fastest-moving glacier.

Pugh, a UN Patron of the Oceans and a former World Economic Forum Young Global Leader, spoke to us about his latest challenge, what it's like swimming in freezing waters and his mission to tell the world what's actually happening to our planet.

Swimming in very cold waters is both mentally and physically challenging, Pugh explains.

"When you get into freezing cold water, trying to get everything into sync is very difficult," he says. "You're just surviving, you're slapping the water and trying to move as quickly as possible. That's what makes this type of swimming so very challenging."

You have to fight mental hurdles too, and the memory of what it was like the last time - otherwise you simply won't get back in, day after day.

"When you have been really, really, really cold, you never forget it. It's deep in your bones and you remember it so vividly," Pugh says. "You can't get into the water unless you're mentally prepared to get into that type of water, because everything, when you look around you, is telling you you shouldn't be getting in there."

Indeed, the water on his latest swim was so cold that he was only able to swim for about 10 minutes at a time - after which it would take two hours for him to recover properly, even with the help of a sleeping bag, three hot water bottles and hot chocolate.

Modern science is also able to paint a vivid picture of what's going on in his body during this time. Pugh would swallow a temperature capsule before he went into the water, allowing him and his team to monitor how his temperature changed.

"Five minutes before I get in the water, we notice my core body temperature is rising in anticipation of the cold," he explains. The team were surprised though at what happened when he went into the water.

"You would have thought my core body temperature would immediately drop. Actually, it's the converse, on some occasions, it was actually rising and kept rising - or kept stable - for the 10 minutes while I do the swim."

It's only once he's out of the water that his core temperature started dropping - and getting back to normal could take nearly two hours.

The swims are about more than the challenge or the science for Pugh, though. They're about raising awareness of the impact of climate change and what's happening to the planet.

He explains: "Data and science are absolutely crucial, but we aren't moved necessarily by data, but by human stories of what is happening and how this will be impacting all of us."

When he first swam in the Norwegian Arctic, the water was 3 degrees Celsius in summer. When he went back 12 years later, it had risen to 10 degrees. "Every single degree of water temperature that goes up makes a huge difference," he explains.

And so you have to tell stories. "You have to explain what it's like. I'm swimming in the water, I'm swimming in the ice, and I've been in the ice for the last 18 years. And I'm seeing the changes and feeling it."

"It's important to use storytelling, to convey a message about what's happening to the planet."

One example of these stories comes from his latest trip.

"I want you to imagine a long fjord," Pugh says. "This fjord is 60 kilometres long. And at the top of the field, you've got the glacier and it's calving icebergs, which is a very natural process, but it's calving away. And then for 60 kilometers, you've got thousands and thousands and thousands of icebergs. And at the mouth at the end of this fjord, there were a number of very, very large icebergs, which were grounded, stuck on the seabed. And they were preventing all these other icebergs from going out to sea.

"And then I remember opening my curtains at four in the morning, getting ready for the swim. And one of these icebergs dislodged. I have never in my life seen anything like it - and I've been operating in the Arctic since 2003. To say it was like a dam breaking, exploding would minimize it. It was like an explosion. Thousands and thousands and thousands of icebergs pouring out - it was like a motorway. It extended 10 kilometres out to sea within a few hours and then all these icebergs started heading north."

"And after a day or so, they were 50 kilometres to the north. And looking out to sea, you couldn't see one piece of open water because it was icebergs everywhere. A timely reminder that we cannot negotiate with the planet."

Messages about what's happening to our planet are difficult but vital to convey, says Pugh. But, the time for action on climate change is now, he believes.

COP26 is "perhaps the most important conference of our lifetime", he says. To tackle the "defining issue of our generation" we need "all hands on deck".

"I cringe when I hear world leaders making promises for 2050 or 2060, when we know perfectly well they won't be around to deliver it," he says. "The sad reality is the glaciers are now moving quicker than our political leaders."

"I've been swimming now year after year in the polar regions. And I know there are so many scientists and diplomats and NGOs working so hard on this, but I have felt like a voice in the wilderness, just literally in the ice saying to people, this matters. This is the defining issue of our generation."

And we need to be far more ambitious in building on the Paris Agreement, he urges. "When you start looking at the commitments nations have made, the vast majority of them don't even live up to what was agreed in Paris," Pugh says. "So my message to world leaders is we need to honour the commitments which we made in Paris and build on them."

The swim might have been incredibly challenging, but really the hard work starts now, Pugh says.

"It's getting world leaders - political, business, community leaders - to understand the speed of the crisis, the scale of the crisis, how it's going to be impacting all of us and urging each one of them to wake up in the morning and ask themselves a very, very simple question, 'What can I do today to help solve the climate crisis?'"

It's not just political and business leaders who can take action, though, he explains. "I always say that every single purchase we make is a decision about our future. It's a decision about our children's future, and it's a decision about the animal kingdom."

And what about Pugh's future? He thinks his days of swims in such hostile environments might be over. But he'll carry on using swimming to share his message of why we need to protect our oceans.

"I love swimming. I want to swim until the last day of my life."

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