Ice cool surfer cheats death to become the first person to ride tsunami wave created by block of 300-foot tall GLACIER crashing into the water

By James Nye

Published: 18:46 EDT, 26 June 2013 | Updated: 10:45 EDT, 27 June 2013

At least if global warming continues, extreme sports can welcome an unlikely new event- glacier surfing.

Daredevils Garrett McNamara and Kealii Mamala have done the unthinkable and spent 20 hours a day over the course of one week in almost freezing waters to become the first people to ride a wave created by 300-foot tall glacier.

McNamara and Mamala, one on a surfboard and the other riding a jetski, completed their stunning joyride at the foot of the Child's Glacier, in south-central Alaska, managing to ride the wave as the thunderous roar of the crashing ice falling into the sea begins.

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August 2007, Cordova, Alaska, USA: Hawaii tow-in surfing team Garrett McNamara and Kealii Mamala have just returned from Alaska where they became the first - and possibly last - surfers to successfully ride glacier-generated tsunami waves

Famed for surfing the world's biggest wave, a 24-meter giant, off the coast of Portugal in 2011, McNamara called the glacier stunt, 'The heaviest thing I've ever done in my life!'

'It's like the Empire State Building about to come down on top of you.

'It was the closest I've ever come to death.

'I was up to my neck in water, looking up at this 90-meter tall glacier, waiting for the ice to break off and hoping that it'll fall straight into the water -- because if it falls flat you'll be squashed under it.'

Death-defying: Their tsunami surfing experience took place at Child's Glacier on the Copper River, in South-Central Alaska, located near the town of Cordova

Stunning: Team members rode waves generated when large ice faces calved away from the glacier, crashing into the waters below and setting off waves that offered rides of up to one minute in length

McNamara and his team spent the week in the water in 2007 simply waiting for a block of ice to fall into the Copper River and create a two-meter high wave large enough to surf.

'I wanted to go home after the first day,' McNamara admitted to CNN.

'But it's fun to be the first to do something. It's a totally new experience -- no one can tell you what it feels like, what to expect.'

As the freezing wave pounds towards the extreme sports enthusiasts the camera zooms in to reveal the sheer magnitude of the 400-ft glacier.

Dramatic: The pair spent nearly three weeks camping at the 400 ft Child's Glacier in south-central Alaska waiting for the perfect wave

Spine-tingling: The adventure was inspired by photgrapher Ryan Casey in 1995 who suggested surfing on glacier waves

For a moment the surfer is completely immersed in the rolling water and the cameraman, unsurprisingly, questions his friend's safety.

'It was way more than I expected,' said McNamara.

'After the first day, I just wanted to make it home alive. Not knowing where the glacier was going to fall, where the wave would emerge, or how big it would be.

'I spent most the time thinking about my family and wondering if I would survive to see them again. It was in a realm all of its own.'

Growing up in Pittsfield, Massachusetts, McNamrara tested the limits of danger from an early age.

'My brothers said I was always the craziest, always pushing buttons,' he said.

'When I was five-years-old I was jumping off two-story buildings.'

Surf's up: Garrett McNamara and Kealii Mamala ride the thunderous and freezing wave caused by a falling glacier

The spine-tingling adventure was inspired by photographer Ryan Casey in 1995 when he was filming for IMAX in the area. He was an avid surfer himself, and noticed the waves.

'If you look at the statistics, it's a lot more dangerous to ride down a highway than a big wave,' he said.

'If you don't make the wave, the jet ski will come get you. In 2000 we started using life jackets, so as long as you can hold your breath under water for long enough, you're OK.'

Hawaiian surfer Garrett McNamara prepares for a surf session at Nazare's fishing harbour on January 29, 2013

The surfers would wait up to several hours in the icy water for a glacier to fall, then chase down the ensuing wave on their jetski and attempt to ride without being injured or killed by ice and rock debris.

'When I surfed the glacial wave it was mind-bending, it was the heaviest rush. But since that day I've found it difficult to get that rush in the ocean. It made me realize how comfortable I feel on big waves.'