diving the top of the world
Talk about cold: three divers have made history as the first to scuba dive beneath the geographic North Pole and get back alive. In a Diver exclusive, UK team-leader Dr Brett Cormick explains how his BC, fins, suit, regulators and his own body started packing up in the sub-zero waters beneath the ice

At first the lights seemed to emanate from somewhere below the water. It was an unnerving and quite disturbing experience in this desolate place, a ghostly lightshow of incredible intensity and beauty, like some underwater Aurora Borealis.
Bob Wass and I are the only two people to have seen these mystical lights and survived to tell the tale. They are another secret that our planet has reluctantly given up.
Shining beneath the North Pole, the phenomenon seems to result from a naturally occurring diffusion of light from the sun, refracting off the many crystal-clear ice formations under water and broadcast through the ever-moving cracks in the surface ice.
I believe it was these lights that were seen by the Russian diver Andrei Rozhkov in April 1998, and which drove him to dive to 50m trying to ascertain their source. With the eventual equipment failure that we must now take as inevitable when diving at the North Pole, his fate was sealed.
Rozhkov was one of the best divers in the Soviet Union, and his was the first attempt to dive at the Pole. The tragedy was heightened by the fact that his support team from Moscow State University, the same group that was to accompany our own expedition a year later, had to sit on his body for three days in a portable oxygen-filled tent-cum-dive-chamber, waiting for rescue during one of the frequent Polar storms that hit the ice at this time of year.

Freefall inspiration
Since Admiral Peary first set foot on the geographic North Pole early this century, a number of people have ventured into this beautiful place. It has a way of drawing you back.
I first decided I wanted to dive at the Pole while tumbling through the air above it. On that freefall parachute expedition, as I witnessed the breathtaking beauty of the curvature of the earth and every shade of white imaginable from the most spectacular vantage point on the planet, I started to imagine what it would be like to invert myself under the ice and walk beneath it.
It took two years of meticulous planning. Diving the North Pole is not something you do lightly. Contrary to popular impression, there is no geographical landmass there. The Pole is simply an assigned point, surrounded by a frozen icecap some 1250 miles across.
This mass of unstable and continuously shifting frozen sea water, between several centimetres and many metres thick, covers a drop of nearly 2 miles to the ocean floor.

Regulator freeze-up
The water temperature in the Polar Ocean is constantly between -1 and -2C, and sea water freezes at -1.8C. Normal scuba regulators are useless at these temperatures, as their water-regulated air supplies freeze as soon as they hit the water.
The external air temperatures of late spring, the most suitable month for weather and ice conditions at the Pole, regularly drop to -40C. So the diver has to submerge himself below the freezing water every time he wishes to take a simple breath from his specially constructed regulator, because the water is much warmer than the air, and this keeps the airstream from freezing.
Additionally, the change in air pressure over the second-stage regulator causes any moisture within the tank to freeze immediately, and stop the flow of air to the diver. So all tanks must be filled in situ, at the exact North Pole itself, or the humidity differential between the air-filling site and 90 North will cause the regulator to fail.
Polar divers also risk being trapped under vast, moving sheets of ice, miles wide. The tectonic plate-like pressure can move millions of tonnes of ice cap in an instant, causing the dive hole to close at any time.
This is coupled with the constant danger of free-floating underwater ice structures, frequently more than 10m high, separating from the ice cap and drifting in the currents beneath the ice.
Polar divers must also contend with the powerful currents beneath the floes, which could sweep them miles away or deep under water in minutes. Once lost, they would never be found.
On a human level, water temperatures below 20C trigger survival reflexes. The heart rate drops, breathing accelerates, circulation is restricted to vital organs and muscles fight for heat by shivering. At each declining degree, these reflexes become more and more ineffective. At zero they are useless. If you were to jump off the ice into the Arctic sea, even in a wetsuit, you would be glad to be unconscious in about 40 seconds - you would be dead in two minutes.
Diving in the high Arctic has been going on for years, but none of these dives ever came closer than about 90 miles to the North Pole, because of the unique logistical requirements of mounting a Polar diving operation.
The only way to get to the Pole is by helicopters from the seasonal ice airport, which is about 60-90 miles away on relatively firmer and older ice. The Pole itself is always shifting: one day it might consist of ice as thick as 6-12m, the next, hundreds of metres of open water.
The divers on this project were Bob Wass from the USA, Michael Wolff from Austria and me, representing the UK. We carried out multiple training exercises in the frozen White Sea during the Russian winter and in the frozen lakes north of Tver, about 120 miles north of Moscow. After extensive testing we decided on two separate diving systems.
Our favourite was the common half-mask with double airflow. This comprised a drysuit with neoprene hood, a tank with a V-shaped valve (two entries) and two non-freezing regulators.
Hoses from the left side connected to the main pressure gauge and suit inflation valve, while those from the right connected to the octopus and BC. The advantage of this set-up was that it was more familiar to divers.
The second and warmer configuration was a surface-fed air system through a deployment hose. The tanks for the air feeds were to be located in a warming tent on the surface to protect from freezing. The diver carried an additional 3 litre tank and regulator on his back for safety. This configuration had the advantage of allowing constant communication with the diver, thanks to an AGA mask with inbuilt microphone connection to the surface, hard-wired to the air-hose feed.
The only drawback was that with an AGA only one regulator can be used, and that is the point most prone to freezing.
The main choice of drysuit was Nordic Pro (Trilaminate) with Nordic Pro inner suits (Thinsulate). Trilaminate is still the only material that does not stiffen in sub-zero water temperatures after being exposed to -40C surface temperatures. For convenience the Thinsulate inner suits were also to be used as our main working clothes at the Pole while preparing for the dive.
The suit could function as a BC should the need arise, but we would always use a BC as well, with both suit and BC inflated by separate air feeds for additional safety. We used the Sea Quest-Aqualung Black Diamond, Tusa Imprex Pro 4900 and Spiro Narval.
The regulator first stage had to be isolated from the water, and the second stage provided with a special device to prevent icing and freezing during the dive. We used the Cousteau D Regulator with dry chamber (Supra D Arctic), which had proved very reliable, as well as the Spiro-Aqualung Automatic Breathing Arctic. The regulators were re-engineered in Moscow to enhance their performance.

Race against time
Time and space are the main factors in a Polar dive, and everything must be completed before the fatigue caused by the cold takes away your ability to function, and before the fuel supply for the generator and heater is exhausted. So our idea was to fly in, set up camp some three miles from the Pole, dive quickly as the dive site floated over 90 North and return to camp.
Because of delays caused by the weather, however, we ended up having to make a dash for the Pole with only one helicopter instead of the two we had intended to use.
That meant abandoning all survival equipment such as tents, rations, heating gear, sleeping bags and other necessities, and taking only what we needed to make the dive. The helicopter was forced to withdraw, leaving us, thanks to solar-storm activity, with no means of communicating with base. We were effectively stranded for at least 40 hours.
We spent 18 of those hours preparing for the dive, which included erecting the air-filled rubber chamber in which divers would be revived on their return. Without this we would risk going into shock and spasm immediately. With no survival equipment, we had to sleep on the icy Polar surface without tents, relying on our survival suits to protect us from the cold.
A specially designed steel water bottle I was carrying in my thigh pocket split in seven places despite my body heat.

The sun never sets
With the sun travelling around our horizon, 24 April was a bright day like every other. We might have had 24 hour sunshine but we also needed 24 hour awareness, because the ice was constantly cracking and shifting. One of the team was always assigned to look out for major cracks developing. These can part in seconds, exposing the ocean below.
It took three hours to hack through the ice to form a "lead" the size of a standard door through which to dive.
I was alarmed to note that even before I entered the water my BC had failed completely and my fins were curling, cracking and disintegrating as they had become so brittle. The physical properties of rubber change at -40C.
Once under the freezing water I found I had been unprepared for the sheer visibility - and the reality of that 2 mile drop, into which I looked with awe and foreboding.
As I descended, my Russian team-mates were already busy breaking up the ice that was reforming overhead. Even a 5cm layer would prevent me resurfacing, and if my equipment failed, as it inevitably would, I could not survive more than a few seconds. The ice pack was moving visibly towards the dive hole and could cover it under more than a metre of ice in minutes.
In the water, first to go were the rubber seals on my drysuit around my neck and left wrist. Freezing water seeped in, sending the left side of my body into spasm. I signalled to the surface team by pulling on my lifeline and was hauled to safety from a depth of 20m. I replaced the equipment and made two more descents, experiencing further equipment failure each time and with my left side still in spasm.
My weightbelt dropped off towards the end of the second dive, as the metal buckle was burst off by the cold. We estimated that it was still dropping towards the ocean floor some 40 minutes after I had been carried to the dive chamber to recover from the dive.
And on the third descent, at about 20m, my regulator finally froze, forcing me to turn to my backup. After a few seconds this also failed, so I was forced to take it out of my mouth and signal with four sharp tugs on the lifeline that I needed to be pulled to the surface as fast as possible.
I made a free ascent, expelling excess air. I believe it was Rozhkov's failure to do the same, probably because he was already unconscious, that killed him. The support team dragged me to the chamber and revived me.
Within 10 minutes of the final dive being completed, the shifting icepack had covered the dive-site permanently.
The background to this spread is the first picture ever taken of the underside of the Polar icecap. Even after two years' preparation, no words could express the beauty and majesty of the ice castles we witnessed floating surreally under water.
We saw jellyfish the size of a man's palm, and shrimp, both totally transparent in this new world, as well as brown and red seaweed growing on the bottom of the thinner and newer ice. A seal swam by 100m from our dive position. Amazing to think that it would be there at all, but then again, why not?
Being the first group to dive the geographic North Pole was a life-defining experience. The camaraderie, the previous fatality, and the opportunity to combine years of Polar training with technical diving, was irresistible. Perhaps it's a new sport, perhaps not. It doesn't really matter, as we are going to do it again later this year.
The North Pole is already drawing us back.

Appeared in DIVER - February 2000