The Denman Terrestrial Campaign is entering its final weeks and scientists have made excellent progress collecting samples, doing surveys and deploying monitoring instruments in a bid to better understand the Denman Glacier system.

The Denman Glacier is one of the fastest-receding glaciers in East Antarctica and has the potential to increase global sea levels by 1.5 metres.

The system is also the deepest-known glacier on Earth, with its base in some places sitting on ground that is more than 3.5 kilometres below sea level.

This may make the Denman Glacier susceptible to rapid and unstoppable ice loss over the coming decades and centuries.

Twenty-seven scientists from a range of universities and disciplines are studying the impacts of climate change on the system from Edgeworth David base camp in the Bunger Hills, 450 kilometres from Casey research station.

It’s the most ambitious deep-field camp the Australian Antarctic Division has coordinated in more than 20 years.

Blue skies then blizzards

The scientists arrived in mid-December and will be there until early February.

For the first few weeks the group had near-perfect weather, before being forced into their tents by gale force winds and blizzard conditions.

“Luckily the good weather means we’re ahead of schedule and the camp infrastructure, including people’s personal tents, has held up really well,” coordinating scientist Dr David Souter said.

“Despite the loss of a few day’s work, morale is high and the collaborative spirit is strong.”

Ice chips provide history of climate variations

Climate scientist Professor Nerilie Abram, from the Australian Centre for Excellence in Antarctic Science (ACEAS) is leading a team that’s drilling ice chips from the Denman Glacier in order to reconstruct the region’s climate history.

Professor Abram and her colleagues spent over almost a month at a remote camp on the Antarctic ice sheet to carry out the drilling.

“It’s the first time Australia has done this type of ice drilling,” she said.

“We drilled down 200 metres into the ice sheet beside the Denman Glacier and those ice chips will give us history of past climate variations and recent climate changes for the region going back around 500 years.”

Professor Abram took the ice chips back to the freezer at Casey research station by plane and spent a few days servicing the drill, before heading back to Edgeworth David.

SAEF team investigates glacier’s distant past

A research team, working with Securing Antarctica’s Environmental Future (SAEF), is collecting samples of lake mud, glacial rocks and beach sand in a bid to understand the glacier’s behaviour over thousands of years.

 “Denman Glacier is one of the largest and most vulnerable glaciers in East Antarctica,” SAEF glaciologist Dr Richard Jones said.

“It has retreated over five kilometres in recent decades but we don’t know if that’s normal or the start of a worrying new trend.

“The rocks record ice thickening and thinning and the lake mud and beaches record local sea level rise and fall in response to the ice growing and shrinking.

“We’re trying to estimate how the glacier changed prior to the 20th Century. Was it retreating, stable, or even advancing?”

International meeting at Bunger Hills

Despite the remoteness of the base camp, the expeditioners are not alone.

A group of Russian expeditioners have set up a temporary camp not far away in the south-western Bunger Hills.

In “broken English over a cup of the finest Nescafe Blend 43” the six geologists from St Petersburg explained to Dr Souter and SAEF UAV (drone) pilots Matt Swan and Julian Galves-Serna that they were continuing long-term geological and topographic mapping of the Bunger Hills.  

“Their surveys are being done mostly on foot but they’ve also been operating a reasonably large fixed-wing drone equipped with a magnetometer that measures changes in the Earth’s magnetic field,” Dr Souter said.

“We were keen to have a chat, not just to say g’day but also to make sure there was no risk of collision between our respective aerial operations.

“They’ve notified us when they intend to conduct UAV operations and our field parties have been helpful keeping an eye and ear out for when it’s operating.”

Last stage turns inland

The focus for the last stage of the Denman Terrestrial Campaign is the Denman transect, a series of sites situated across the glacier.

A range of instruments is being used to measure different aspects of the glacier – how fast it’s moving, how deep the glacial basin is and what the bed of the glacier looks like.

The answers will provide insight into how much ice there is in the Denman Glacier system, how fast it’s moving out to sea and whether this is likely to change.

Although the living conditions are austere, field leader David Knoff said everyone had adapted well to remote living.

“Everyone seems almost sad that it has to end soon,” he said.

“They’re really settled into life out here in our little village.”

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