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Heimaey is the largest of the Westman Islands, an archipelago south of Iceland mostly inhabited by puffins. On Stórhöfði peninsula, at the southernmost point of Heimaey is an outcrop that juts into the Atlantic Ocean. The local weather station here claims to be one of the windiest places in Europe.
It was here, in the early hours of March 12 1984, that 23-year-old Guðlaugur Friðþórsson stumbled towards salvation. His bare feet were bleeding from deep cuts caused by the volcanic rock hidden beneath the snow, his clothes soaked in seawater and frozen to his body. He should have already died several times over, but something deep inside Friðþórsson propelled him forwards.
The night was clear and cold. The air temperature was -2C (28F) but with strong winds it would have felt much colder. Despite the freezing temperatures, he paused at a bathtub filled with water left out for sheep for a brief respite. Punching through the centimetre-thick ice he began to gulp down water from the trough.
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It is perhaps strange that a drink of ice cold water was a primary concern at a time like that. But dehydration is a surprising concern in cold environments as the air in sub-zero temperatures is essentially freeze-dried. With no moisture in the air, when he breathed out, he was losing vital fluid from his lungs. It is why you can see your breath hanging in the air on a cold night.
But the cold also appears to blunt our sensation of thirst, meaning many people do not take in enough water. If you are working hard to stay warm, and breathing heavily as a result, it can quickly lead to dehydration.

A French soldier melts snow as part of a training exercise (Credit: Getty Images)
“You tend to see a lot of problems with cold compounded by dehydration,” says Mike Tipton, professor of physiology at the University of Portsmouth.
Having found fresh water, however, dehydration was not Friðþórsson’s biggest problem. His wet clothes were quickly making his condition worse, putting him at risk of hypothermia, which occurs when the core body temperature drops below 35C (95F). While exercising, he could keep his core temperature high. But having stopped to take a drink, his source of heat – generated by the movement of his muscles – had been cut off. While he still had calories to burn, he had to keep moving.
At maximum exercise, it is like you are running a 2kW fire – Mike Tipton
“A man in the cold is not necessarily a cold man,” says Tipton. “If you keep moving and you are reasonably insulated you will produce enough heat to stay warm. At maximum exercise, it is like you are running a 2kW fire. When you exercise reasonably hard you can do that in shorts and t-shirt in the cold. Even when you have to shiver you are essentially engaged in light exercise.”
People at high altitude might find exercising more difficult. Tipton says that climbers on Everest might only be able to manage one step every 10 seconds. Heat production at this rate of exercise is minimal, so staying warm is very difficult.
Records of climbers who have succumbed to the cold at altitude are plentiful, often because radio communication can be maintained until they fall unconcious. In one harrowing account of several climbers stranded on Peak Lenin in a blizzard in 1974, their final moments were relayed to base camp.
The group, led by Elvira Shatayeva, were attempting to become the first all-women group to scale the mountain, in modern-day Tajikistan. As they grew colder, their thoughts became increasingly disoriented and they spoke of how weak they were becoming: “Another has died,” Shatayeva is recorded as saying in one of her last messages, “... I do not have the strength to hold down the transmitter button.”

At maximum exercise, heavy layers of protective clothing are not required to stay warm (Credit: Getty Images)
While there is evidence that extreme heat affects people’s cognitive abilities, it is less clear what, if anything, extreme cold does to the mind. In one paper, people dunked in 2-3C water for three minutes (enough time for someone to develop and get over the cold shock response) saw a decline in their short-term memory but improved in other areas, like their alertness. Another paper found that people brought very close to the point of hypothermia (their core body temperature was lowered to 35.5C) suffered no decline in cognitive function at all.
It would appear that our brains are much better at coping in the cold than dealing with being too hot. This is because our bodies’ survival strategies centre around keeping our vital organs running at the expense of less essential body parts. The most essential of all, of course, is our brain. By the time that Shatayeva and her fellow climbers were experiencing cognitive issues, they were probably already experiencing other organ failures elsewhere in their bodies.
Our bodies are very good at reducing blood flow, through a process called vasoconstriction, to our hands and feet to preserve our core body temperature. But in doing so, we sacrifice heat in those extremities. Human tissue freezes at around -0.5C. As fluid in our tissues begins to freeze, our cell walls break leading to necrosis, or cell death. We call this frostbite.
However, being close to the point of death from hypothermia can apparently do strange things to the mind. In some rare cases, people suffering from extreme cold appear to feel hot in the moments before they die. Some bodies of hypothermia victims are found partially dressed, or even fully undressed, in a phenomenon called “paradoxical undressing”.
It might be that at the very last moments before death, the mechanism that holds blood below our fat layer fails, causing it to rush to the surface of the skin and giving the sensation of being flushed with warmth. In reality, the victims suddenly lose huge amounts of heat. Getting undressed only speeds up how quickly they die.
Most of these cases (67% of men and 78% of women) involve people who have consumed alcohol, which is known to inhibit our thermoregulatory response.
Like with paradoxical undressing, it would appear that in the very last moments before death the victims are overcome with confusion
In other unusual cases of death by hypothemia, victims have been found hidden behind wardrobes or under beds. This phenomenon is called “hide and die syndrome” or sometimes “terminal burrowing”, although examples of people who have burrowed are extremely rare.

Even at -32C (-20F), people who are strenuously exercising do not need gloves. The best gloves will only work for up to 3 hours at rest (Credit: Javier Hirschfeld/ Getty Images)
Like with paradoxical undressing, it would appear that in the very last moments before death the victims are overcome with confusion. About a quarter of these people also undressed themselves before hiding.
Those few people who have been found frozen to death and paradoxically undressed frequently fell victim while walking home at night in improper clothing, sometimes drunk. For anyone in a survival situation, there are three lines of defence that protect against the cold.
“Clothing or equipment is the first line of defence, shelter is second and third is fire,” says Jessie Krebs, a former US Air Force Survival, Evasion, Resistance and Escape (Sere) Training Instructor. “People will skip right to fire after clothing has been compromised, which is a mistake. If they are not successful they die trying to start a fire.”
This was the situation that faced 30-year-old adventurer Tyson Steele at the end of 2019. Thick snow blanketed the remote, forested corner of the Susitna Valley where Steele’s cabin stood. He slept wrapped up warm against the freezing temperatures outside while the remains of his fire glowed in the wood-burning stove.
A tiny ember drifted up the chimney and settled on the tarpaulin, that formed much of the roof of his hut, where it quietly smoldered. At the smell of the fire, Steele dashed outside to find flames bursting from the plastic roofting. Within a few minutes the whole hut was ablaze.
This was the start of what would become a three-week ordeal for Steele, stranded 20 miles from the nearest town in sub-zero conditions in the Alaskan wilderness. Over the following 20 days or so, he faced a battle to stay warm and alive in the hope of rescue.
Unable to move far in the deep snow, his plan was to stay put, which under the circumstances was not a bad one. After clothing, shelter is next in the hierarchy of defence against the cold. He salvaged some canned food and blankets, built a shelter out of debris from his hut, and lit a fire.

Tyson Steele waves to the circling State Trooper helicopter surrounded by the debris of his hut (Credit: Alaska State Troopers)
At this point, Steele’s outlook was pretty positive; his three lines of defence were in order. He stomped out an SOS message next to his hut and waited for help.
“If you know help is coming, you are better off digging a snow hole and staying put,” says Tipton. “People in Canada say all you are doing is staying put until you die because no one will find you. But if you are fit and have food, if you sent a mayday and you know they will be coming you are better off building a snow hole and not heading into a blizzard.”
While staying at the cabin he had kept in touch regularly with his family, and posted on social media. But when those messages went quiet, his family grew concerned. Fortunately for Steele, his silence was noticed and ultimately saved him, not his SOS.
“The SOS signal is what most people know, but the downside is it is very curvy,” says Krebs. “Most of nature is curvy – it is rounded hills and lakes and streams, so curvy blends in.”
In the military Krebs was taught to use the letter “V” to request general help or an “X” specifically for medical assistance. The long straight lines stand out on a hillside. It also takes less time to create two straight lines 30 feet long compared to two loopy Ss and one O, each 10 feet high.
Provided you are certain that the pilot has seen you, lying down quickly communicates that you are hurt or sick and therefore need assistance urgently – Jessie Krebs
The footage of his rescue, recorded from a helicopter circling above him, shows Steele waving with two arms aloft to his saviours while standing in front of his SOS. While two arms in the air is widely recognised to be a request to be picked up (only one arm could be misinterpreted as a greeting), Krebs says the most effective way to communicate distress is to lie down on the ground. Provided you are certain that the pilot has seen you, lying down quickly communicates that you are hurt or sick and therefore need assistance urgently.
Other forms of ground to air communication include using signal mirrors. A mirror from a car sun visor can be repurposed for this. Holding the mirror over one eye and aiming by fixing the target between your fingers held out in front of you in a “V”, a signal mirror can draw attention up to 50 miles (80km) away in clear skies. Other alternatives are smoke signals – the water in branches and leaves from fresh vegetation creates white smoke when burned, which is useful in dark forests. Burning rubber or car tyres can produce black smoke that will stand out against snow. But Krebs warns this is only really useful if there is an aircraft in the area.
Steele later admitted he had no formal survival training, but had picked up some knowledge from YouTube videos. A few matches, a candle and some birch bark helped him to start a fire, which he could use to keep dry.
Being able to maintain and repair clothing is essential to increasing your chances of survival says Krebs. In a worst case scenario, wet clothes can be wrung out and pushed through powdery snow to absorb some water. But in Friðþórsson’s case, he was already way beyond this point.

A soldier takes part in Sere training in Colville National Forest, Washington, on a freezing January morning (Credit: Getty Images)
Friðþórsson had fallen into the sea just east of Stórhöfði peninsula when his the small fishing vessel, Hellisey VE 503, ran into trouble. At 10pm, her trawl net caught on the ocean floor capsizing the boat so quickly the crew had no time to send a distress signal.
Her five fishermen were thrown overboard. Three of them managed to scramble onto the keel of the upturned fishing boat, two never resurfaced.
An average person will survive in water colder than 6C for about 75 minutes, to swim three miles in these seas would take hours
The survivors found themselves separated from shore by three miles (5km) of 5-6C (41-43F) sea. An average person will survive in water colder than 6C for about 75 minutes. Accounts of people surviving for longer are anecdotal and few. In laboratories, test subjects begin to suffer adverse effects within 20 or 30 minutes before they are pulled out. To swim three miles in these seas would take hours.
Seawater cannot get really, really cold like air. Seawater freezes at about -1.9C (28.6F), but around Iceland in March the sea is just above freezing. It is theoretically possible to get frostbite in cold water, then, but very unlikely.
On the keel of the upturbed boat, however, the sub-feezing air temperature was taking its toll. The fishermen’s wet shirts, sweaters and jeans were quickly exacerbating their coldness. Staying put was not an option.
“When you come out of the water you get evaporative cooling,” says Tipton. “This is a really potent way of losing heat from the body.” Ordinarily you would want to strip off and put dry clothing on, but in the absence of that, climbing into a large plastic bag will reduce evaporative cooling and convective cooling.
“If you get someone wet at 4C and they have got a litre of water in their clothing; if all of that water evaporates they are going to have a fall in body temperature of 10C,” says Tipton. “If you put them through the same scenario and then put them in a plastic bag they can use their body to heat up that water. It is contained in the bag so it cannot evaporate away. Those people lost half a degree, so they were 20 times better off."

The fishermen were separated from land by three miles of frigid sea (Credit: Getty Images)
Tipton says one of the big successes his team at the University of Portsmouth have had was to encourage the Royal Canadian Mounted Police to ditch their expensive foil space blankets in favour of cheap, tough, plastic survival bags. Space blankets, the kind that are wrapped around marathon runners at the end of races, are good at protecting against radiative heat loss, but less good when it comes to evaporative heat loss, because they do not trap fluid. In a survival situation, a plastic bag would be far more useful.
Without a plastic survival bag, and now in the cold air with the seawater evaporating off him, Friðþórsson’s risk of freezing cold injuries was very high.
In all, it took Friðþórsson six hours to swim to land, the two others succumbed after 10 minutes
After a short while deliberating, the three men decide to risk the swim. Within 10 minutes, the two others had succumbed to the cold. In all, it took Friðþórsson six hours to swim to land. How was he able to survive for so much longer than his compatriots?
For the fishermen, the first few minutes after hitting the water were critical. Cold water takes heat away from the body quicker than air at the same temperature. Those that succumbed quickly were probably unable to control the cold shock response. Gasping and panicking, they inhaled water. Friðþórsson, by contrast, managed to control his breathing.
He later described remaining clear-headed throughout his swim. He even chose to get back in the sea to swim further along the shoreline after the cliffs at his first landing spot proved too difficult to climb. The presence of mind to do this probably saved his life.
Finally, Friðþórsson reached a village, and around 7am on Monday morning he knocked on someone’s door. He was later discharged from hospital having been treated for his cuts and dehydration. There was no sign that he had suffered from hypothermia at all.
Friðþórsson, now 58, is a large man. He stands 6’3” (193cm) and weighed 19.6 stone (125kg) in his twenties. A generous layer of fat about two and a half centimetres thick wraps his abdomen. His body fat kept him insulated, but it was also a vital source of energy.
Even so, his ability to stay warm was exceptional. Researchers who conducted tests on Friðþórsson after his ordeal concluded that he must have been able to maintain near normal body temperature for the entirety of his swim.
Unlike other extreme survivors, Friðþórsson has not made his story into a money-spinner. A 2012 independent Icelandic film is the sum total of the mainstream coverage. The clothes that he wore, now on display in the Eldheimar Museum on Heimaey in a small exhibit to the island’s fishing history, are a modest recognition for his remarkable story.
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