Greenland Inland Traverse (GrIT), explained

The GrIT fleet parked on the ice sheet under the fading night sky. Photo: Robin Davies As you've recently read here, the Greenland Inland Traverse (GrIT) crew returned to Thule Air Base in northwest Greenland in March to begin prepping for the nearly two month long operation to transport thousands of pounds of equipment, fuel and supplies to Summit Station situated at the peak of the Greenland ice cap.

The team set off on the 1400-mile round-trip traverse this week. Along the way they will battle harsh conditions, forge a new route through crevasse fields and test a new cargo transport design. They must make their deliveries and trek back to Thule all before May 31, when the ice becomes too wet and dangerous.

“The bulk of the fuel we’re moving is destined for Summit Station with smaller amounts for GNET and the Sunlight Absorption on the Greenland ice sheet Experiment traverse [two NSF funded research projects],” Geoff Phillips, GrIT operations manager, said. “Aside from fuel we are also delivering 52 drums of drilling fluid, 200 Helium cylinders, a new Caterpillar tracked loader, and Summit operations and construction resupply materials."

The GrIT team hauling bladders up the ice cap. Photo: Robin Davies

Tough Conditions, Tougher Equipment

Phillips and his crew will use highly modified Case Quadtrac tractors with 485 horsepower engines to pull four, 8-foot-wide pieces of specially formulated high molecular weight plastic. The plastic sheets form custom-built sleds that are 32-feet wide, 80-feet long, and can pull over 170,000 pounds of fuel and cargo each.  This year, goods will be hauled on two cargo sleds and two fuel sleds pulled by the 4-tractor fleet.

This design is a core component of both the cargo and fuel sled systems. To transport fuel, the team will load two sleds with eight fuel bladders containing 3,000 gallons each, totaling to approximately 45,000 gallons (310,500 lbs!) of fuel. Providing a smooth ride for some 240,000 lbs of cargo is a little trickier, and GrIT is taking a new approach.

“The cargo decks have really changed dramatically over the years. It started with just putting cargo essentially on top of these plastic sheets. But we quickly discovered that cargo gets thrown around and off the sleds against your best efforts to strap it all in,” Phillips said.

Jim Lever, his Cold Regions Research and Engineering Lab associates, along with GrIT and the South Pole Overland Traverse teams, went to work on this problem and developed a solution using air-filled pontoons between the cargo deck and the plastic sled.

The initial testing used whitewater raft tubes and stick-framed cargo decks to pull heavy loads over relatively short distances.  The current Air-Ride Cargo System design has moved beyond that: custom pontoons and pouches are bolted to the plastic sleds and cargo decks, can handle temperatures well below -40F, and can take the abuse of hauling tons of cargo over very long distances without damaging the sleds or the cargo above them.

“The lifespan, durability, and performance of the sleds and their components have improved dramatically over the relatively short time the traverse has been in operation.  It has been a great example of successful teamwork between two large projects and government agencies,” Phillips said.

GrIT 14 New Route

Forging a New Route

In addition to trying out the new ARCS design, GrIT 2014 will take a different and slightly shorter route to Summit Station this year. Usually the traverse leaves Thule and makes a stop at a European research station called “NEEM” northeast of Thule before heading to Summit Station.

“We generally resupply NEEM with fuel, but it’s been shut down for two years now. This year, a group of albedo researchers [called SAGE] are doing a snowmobile traverse in the same general area, so we are rearranging our outbound route to deliver fuel to them at various stages along their traverse,” Phillips said. Lead investigators Zoe Courville and Chris Polashenski are leading the National Science Foundation-funded albedo research.

A 2012 photo of on of the Case Quad Trac tractors pulling cargo in the crevasse zone. Photo: Galen Dossin

Preparation is Key

As you might imagine, A LOT of planning and preparation goes into GrIT missions. The planning has been ongoing with GrIT 2014 specifics being determined as early as 2012.  In early March, a preparation team 12 people strong arrived at the air base to find a route, modify equipment and support the five-person team that will complete the traverse.

One key part of this prep phase is mapping a safe route through the crevasse fields that they will encounter along the first 70 miles. A small group called SCAT (Strategic Crevasse Avoidance Team) made day trips out of Thule to locate, map, and share a route for the GrIT tractors.  You can read more about SCAT at:

Galen Dossin and Allan Delaney heading out on a SCAT mission. Photo: Brian Buckley

A Specialized Crew

The 2014 GrIT mission is not only well equipped with specialized equipment to get the job done; it also pulls together a team of highly specialized people with a variety of backgrounds. The team is made up of mechanics, carpenters, heavy equipment operators, mountaineers, radar technicians, engineers, and an electrician, with close to 180 years of combined polar experience and ingenuity.

Many on the team have honed their unique set of skills by taking part not only on previous GrIT missions but also on Antarctic traverses, including the South Pole Overland Traverse, and at numerous field stations.  One thing that connects them all is the drive to meet a challenge and solve it.

“We all like solving problems and there is a never-ending supply of problems up here,” Phillips laughed. “It’s really interesting work! It’s not like this is done often enough that all the kinks are figured out. We get the best group of people we can and then work through the problems as we find them." —Alicia Clarke

The Arctic Research Support and Logistics Program within the National Science Foundation’s Division of Polar Programs funds the Greenland Inland Traverse. CH2M HILL Polar Services and Cold Regions Research and Engineering Laboratories are working together with the NSF to develop the traverse infrastructure and route to Summit Station. The 2014 spring traverse delivers fuel and cargo to Summit Station, continues efforts to optimize mobility, and provides a research platform for an NSF-funded scientific research project. For more field notes coverage of GrIT, click here.