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The Canadian High Arctic Seismic Expedition 2011
by Hans Böggild

Featured in Above & Beyond July / August 2013

A young RCN Lieutenant in 1948, my father was summoned to Ottawa by the Dominion Hydrographer and given a mission to correct old Admiralty charts of the Northwest Passage. He soon found himself on a RCAF floatplane, leaving Edmonton for Tuktoyaktuk, flown by a pilot whose only map was a pencil sketch on the back of an envelope.

My father began taking soundings in the waters off Tuk with the help of two Catholic priests who loaned him their motorboat. A week later, RCMP Vessel St. Roch appeared and Inspector Henry Larsen, the vessel’s Captain and the first man to navigate the Northwest Passage in both directions, agreed to attach my father’s depth sounder to his ship. My father joined Larsen on the St. Roch for three months. They became friends for life.

Inspector Larsen often visited our home when I was a boy. He and my father would play chess and recall their adventures. Before he died, Larsen sent me a postcard with a picture of himself as a polar hero, wearing a parka, his beard grizzled by ice and snow. He signed it, “Uncle Henry.” When I look at that postcard it reminds me of my father and Larsen telling stories about what seemed to me a mythical land, the Arctic.

Fast-forward to August 2011, and I find myself on a 737-charter flight out of Edmonton bound for Kugluktuk, Nunavut. The 20 other passengers on the plane are scientists and technologists. I’m 55, have never been to the Arctic, or gone to sea. My job is to write the blog of the Canadian High Arctic Seismic Expedition aboard CCGS Louis S. St-Laurent as we survey vast sections of the Arctic Ocean for the next six weeks. The voyage is the last of a series to gather seismic and bathymetric data in the Western Arctic in support of Canada’s submission to UNCLOS, the United Nations Convention on the Law of the Sea. The information will determine Canada’s sovereign rights to ocean areas beyond the 200-mile limit. It will define which areas of the open sea are natural extensions of our continental shelf.

Sitting next to me on the charter is Dr. David Mosher, Chief Scientist of the expedition. Originally from Truro, Nova Scotia, he’s a family man, a marathon runner and an excellent Celtic flute player. He’s also a world authority in geology and oceanography with a focus on geophysics. As a geologist, he’s interested in the Western Arctic from a tectonic point of view and how the area may have formed. He also appreciates the expedition in another context. “This is the latest in the whole history of exploration in the Arctic,” he says. “We are working in one of the last frontiers in the world and finally able to explore it in some detail.”

Our plane lands and we cross the tarmac towards Kugluktuk’s tiny airport, within sight of Coronation Gulf. Through morning fog and patches of sun I see CCGS Louis S. St-Laurent at anchor just off the coast.

In the airport, we meet members of Louis’ crew who arrived earlier from St. John’s Newfoundland. All of us fly on a small red DFO helicopter to Louis’ flight deck.

Aboard Louis, Coast Guard specialists provide survival training. Muster drills summon us to our lifeboat stations. We practice putting on immersion suits.

Louis passes through The Northwest Passage and out into the Beaufort Sea. We experience rolling seas as we voyage north.

Soon we encounter our first sea ice. It’s a mixture of thinner first-year ice and multi-year ice, larger chunks that are cobalt blue on the bottom. The ship’s movement becomes more vertical and ice scrapes the hull. We’re on our way to rendezvous with U.S. Coast Guard Cutter Healy.

The 2011 expedition is a joint Canadian American survey. The difficulties of Arctic seismic exploration became clear in 2007 during Canada’s first efforts to acquire data. The seismic equipment became damaged by heavy ice and progress was almost impossible. Those involved realized that the mission could only be accomplished using two icebreakers, one to gather data while the other broke ice. The United States was also gathering data for its continental shelf interests with its flagship ice-breaker U.S. Coast Guard Cutter Healy, equipped with a multi-beam bathymetric sounder. Canadian and American scientists realized that collaboration on the voyages would yield better quality data and cost savings for both countries. This led to collaboration and joint surveying missions in 2008, 2009, 2010 and 2011.

At 78 degrees north, Louis manoeuvres alongside Healy and deck crews install a gangway. Officers, crews and scientists tour each other’s vessels. I look at Healy’s bathymetry lab. The Healy’s multi-beam bathymetric sounder can map the ocean floor in a swath as wide as 70 degrees as the ship moves along. Bathymetry is a measure of the water depth, analogous to topography above the water. In the evening, the ships disengage and transit further north.

Bathymetry and seismic exploration both use sound waves travelling through water and bouncing back to sensors to gather data. Bathymetry measures the depth of the ocean to the seafloor. Seismic exploration creates a profile of the Earth beneath the seafloor to tens of kilometres depth. The unique challenges facing Dr. Mosher and his Seismic Team involve dealing with extreme cold and Arctic sea ice.

Borden Chapman, Chief Seismic Technician, enjoys making difficult things work. The majority of seismic acquisition over water takes place in open water, with equipment towed on the surface behind a ship. When it has to happen with chunks of ice as big as boxcars trailing off the stern of an icebreaker, a different approach is required. Borden and his team redesigned the seismic array to deploy under the Arctic ice making hundreds of modifications to make it work. Borden plans for equipment failure in the Arctic and has replacements for every part of the array, explaining, “You can’t go to Canadian Tire when you need a hose clamp.”

Seismic exploration begins. Marine Mammal Observer Nelson Ruben takes his position on “Monkey Island,” the observation deck above the bridge. Nelson is Inuit, an experienced hunter and guide. He scans the horizon with a sophisticated pair of binoculars. In the event that a mammal comes within 1,000 metres of the ship, seismic work ceases until it leaves the area.

On the quarterdeck, the Seismic Team and Louis’ deck crew deploy the seismic gear. Every move is choreographed to prevent entanglements with ice. The equipment is guided off the stern and lowered to a depth of 11.5 metres.

In the seismic lab, Borden radios Nelson who confirms there are no mammals in his sights. Borden fires a “mitigating shot” of each air gun, to warn any mammals that might still be nearby, giving them time to leave.

On the bridge, Captain Marc Rothwell, a seasoned Arctic mariner, moves Louis forward. He follows a track in the ice created by Healy a mile ahead of us, proceeding at the slow speed of four knots required for seismic exploration. The slow speed creates restrictions from a ship-handling point of view. Louis has three propellers but Captain Rothwell can’t use his powerful centre shaft propeller, which could damage the seismic array towing behind the stern. He can’t push water directly past the rudder, which reduces his ability to steer. This difficulty is compounded by thousands of pounds of pressure exerted by the ice pack itself, pressure created by winds and ocean currents. Captain Rothwell explains, “It’s like a vice grabbing on to both sides of the ship.”

In the seismic lab, the steady bang of the pneumatic guns firing every 17 seconds emanates from beneath the stern. Dr. Mosher and Borden Chapman look at a computer screen showing 16 vertical waveforms representing the reflections of the sound wave bouncing back from the Earth’s sediment layers. The 16 waves are stacked, added and processed, providing a high-resolution profile of the Earth’s composition many kilometres below the ocean floor.

I join Dr. Mosher on the helicopter to deploy a sonobuoy, a receiver that captures the reflected sound wave from a different position and transmits it back to the ship. Its use gives greater dimension to the seismic results.

The helicopter lifts off from the flight deck and we fly 20 miles north over the frozen ocean. Our pilot sees a small pool of open water beneath us and descends to sea level. Dr. Mosher opens his side door and hurls the sonobuoy straight down into the water. The helicopter banks around and climbs to a high altitude. The view is astounding. One gets a sense of the vast scale of the Arctic horizon with ice in every direction making a complete 360 degrees. I feel something similar to what the early astronauts must have felt when they looked back at the Earth from space. Everything seems completely insignificant from this vantage point. Soon we see two tiny red ships in the distance, Healy and Louis, on a vast endless plain of ice.

Moving forward to 85 degrees north, the ships encounter ice under enormous pressure. Our ship grinds to a halt. We’re stuck.

Healy turns around and cruises past our port side making a track beside us that relieves the ice pressure. Once past us, Healy turns around then pulls ahead of us on our starboard side, making another track, relieving more pressure. We move forward. This manoeuvre happens repeatedly as we get stuck and dug out over and over again. Twice the seismic array becomes damaged by heavy ice. Twice the Seismic Team rebuilds it, working through the night in the midnight sun on both occasions. We collect excellent seismic data all the way to 88 degrees north.

During the nightly meeting of assembled science staff, Dr. Mosher announces, “Things are looking good from a seismic point of view, so we’ll be searching for an open pool to deploy the AUV.” The Autonomous Underwater Vehicle is a newly developed unmanned submarine with a mission to launch from the ship, transit 48 hours under the Arctic ice gathering multi-beam bathymetry of the sea floor, and return with its data.

It’s a tall order for the AUV to return to the same open pool in the ice where it is launched because Arctic ice drifts up to 10 kilometres a day. The pool will inevitably have moved a significant distance when the sub returns. Since GPS doesn’t work underwater, the question of how it will know where to surface is an important one. The AUV is equipped with a host of innovative systems specifically designed to meet this challenge.

Richard Pederson of Defence Research and Development Canada is leader of the AUV Team, which consists of seven technologists from DRDC and three submarine engineers from International Submarine Engineering who manufactured the sub. They tested the AUV at a remote ice camp off Borden Island in 2010, drilling a hole in the ice to launch it, and the sub returned to the hole.

Canadian satellite radar pinpoints a suitable open pool 60 miles away and we transit towards it. Louis can now use all of its power and breaks through the ice at high speed. It’s a bumpier ride and we secure loose items in our cabins. We arrive in the open pool and stop. It’s just large enough for
the ship to turn.

The AUV Team has brainstormed every contingency that might occur on the sub’s mission and made plans for every variable. They’ve pre-programmed up to 80 alternative responses to any situation the sub might encounter beneath the ice. Now it’s show time.

Louis’ deck crew rolls the AUV onto the flight deck and attaches it to a giant crane. With precision rope handling, it’s hoisted high above the ship and lowered over the starboard side. Ballasting, buoyancy, underwater acoustics and positioning systems are adjusted. Richard Pederson gives the order to release the sub and it sinks below the waves.

The AUV Team tests the sub’s systems as it descends in a pre-programmed spiral pattern to a depth of 3,600 metres. When the sub is 130 metres from the seabed, it forays out under the ice for five kilometres then returns.

Richard Pederson learns of a malfunction with the sub’s forward-looking altimeter, which is designed to help the sub avoid objects ahead. He’s faced with a difficult choice. If he aborts the mission, he may not get another opportunity on this expedition to deploy and the AUV will not achieve its objectives. If he doesn’t abort the mission, he risks the sub colliding with something underwater and losing it completely. He aborts the mission.

The AUV rises to an area below the ice on the starboard side of the ship. The Remotely Operated Vehicle (ROV), equipped with high definition cameras, is deployed off the ship and ventures under the ice. The small unit has its own propulsion system and connects to the operator on the ship
through an umbilical cord. There’s a hook on the ROV designed to attach a line to the AUV. This method successfully recovered the sub on the ice camp.

Two video screens display the ROV’s view underwater. The ice under the surface is a series of downward protruding ridges, and huge upward crevices, where the sub is located but obscured from view. The ROV is deployed twice, but can’t get a view of the sub.

The wind picks up, and chunks of ice clutter the open pool. Louis’ bubbler system shoots compressed air into the water to clear the rubble away as the ship moves around. The ROV is deployed again but can’t get a visual. After 12 hours of hard work in freezing weather, the deck crew is released for rest. Recovery operations will resume tomorrow and the AUV will wait under the ice until then. The mood is one of determination and some concern.

Dr. Mosher decides that another science project, the installation of the O-Buoy on the ice, can happen tomorrow while the AUV recovery continues. The O-Buoy is a self contained Arctic buoy that can measure the atmosphere for up to two years. I’m asked to go along.

Next morning, the helicopter shuttles 11 of us to an ice floe roughly four miles from the ship. Dr. Stoyka Netcheva, Atmospheric Scientist with Environment Canada, is leader of the project and the rest of us are there to help her. Through the day we drill a hole through the ice floe and connect all the parts of the O-Buoy. It’s a team effort with a satisfying moment at the end when Stoyka turns on the buoy and all of its systems work. We step back to look at it. Each of us signs our names on its base in permanent marker. We’ve put the O-Buoy on the ice at 88 degrees north.

Standing on the ice floe, we receive news via radio that the AUV has been recaptured off Louis’ port bow. We high-five our gloves and look towards Louis. From a distance we see the yellow submarine hoisted high above the ship by the giant crane.

We fly on the helicopter back to Louis. Everyone aboard celebrates the recovery of the AUV, a happy mixture of relief, exhaustion and exhilaration. There’s an impromptu jam session of Newfoundland sea songs and Gordon Lightfoot tunes. New acquaintances weeks ago are now friends for life. There’s hope the AUV will get another chance to deploy, but that will depend on the success of seismic work in the next section of the voyage.

Louis and Healy alternate taking the lead breaking ice. When Louis leads, Healy follows collecting multi-beam bathymetry. When Healy leads, Louis follows collecting seismic data. We transit over Makarov Basin, Mendeleev Rise, Alpha Ridge and Sever Spur. The ice gets progressively thicker.

Crash! We slam into a pressure ridge. Pots and pans go flying in the galley, tables and chairs slide around the crew’s lounge, closet doors burst open in our cabins. Louis leans hard to port for an eternity of seconds then straightens up again. On another track we must repeatedly back and ram, making 19 attempts on one piece of ice before breaking through.

At 80 degrees north, Dr. Mosher tells me, “We are further east at this latitude in the Arctic Ocean than any ship ever before.” The ice here is the toughest left in the Arctic, and the fact that we are here in a ship at all demonstrates the loss of multi-year ice that allows us to make any passage whatsoever. We’ve made history.

Dr. Mosher approves another deployment of the AUV. We transit to the closest open pool off the coast from the Canadian Arctic Archipelago.

Jane Eert, Physical Oceanographer for the Department of Fisheries and Oceans, does a CTD\Rosette test, getting information about the water’s salinity, temperature and depth down to the seabed. Jane has collected water samples throughout the voyage as part of a study on Arctic Ocean currents and water masses. Jane’s information about salinity is useful to the AUV Team because it gives them an understanding of the level of buoyancy to expect when they deploy the sub. Jane gives this information to Richard Pederson.

The AUV deploys flawlessly and ventures out under the ice on its mission. Louis is relatively quiet for the first time in weeks. In the hangar, the AUV Team monitors their equipment 24/7, waiting to hear a chirp from the sub.

The next evening, Richard learns that the chirp has come back. The AUV has reached its final waypoint and it’s heading home to Louis. The next morning, the sub returns to an area just below the ice, 117 metres from the ship. The fact that it has returned at all is an achievement, because our position has changed considerably since it was launched. Recovery begins at 10 am.

Richard arrives on the bridge, carrying a hand-held radio, communicating with his team all over the ship. He receives ranges of the sub’s location and relays them to Captain Rothwell who carefully manoeuvres Louis using the ship’s powerful bow to create small cracks in the ice. At 11:05 am the sub surfaces in one of the cracks. A seaman and a technologist go over the side in a basket. They secure lines and the AUV is hoisted aboard by 1:28 pm. Recovery that took two days on the first deployment is accomplished in three and a half hours.

The AUV Team successfully retrieves the bathymetric data from the sub and celebrates pushing the bounds of technology. Richard Pederson says, “We’ve proven we can deploy AUVs from an ice-breaker in the Arctic.”

Louis and Healy come alongside at 79 degrees north. Everyone gathers in Healy’s hangar for a “Raft Up” dinner to mark the collaboration between two Arctic ships and their joint survey of 3,000 kilometres of previously uncharted territory.

Soon thereafter Healy breaks off bound for Alaska. Louis heads south towards the Northwest Passage. As we enter those fabled waters I recall my father’s journal from 1948.It truly resonates now. I appreciate how challenging it is to explore the beautiful, remote and unforgiving environment of the Arctic, still one of the world’s last frontiers.

Hans Böggild is a Halifax-based freelance writer, playwright, stage director, actor and blogger. In 2011 he joined the scientific team on CCGS Louis S. St. Laurent to blog about the Canadian High Arctic Seismic Expedition 2011 for the Department of Fisheries and Oceans. See http://blogs.science.gc.ca/arctic-Hans Böggild arctique/2011/08