Hot water is playing a key role in understanding how Antarctic ice responds to a warming world.
Research camp - the large tent houses the hot-water drill, used to drill through 600 metres of ice to access the seawater below the Ross ice shelf. Photo: Do Gong
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Martin Forbes, from the University of Otago, dropping a gravity corer through a hole made by using hot water to drill through 600 metres of ice. Photo: Do Gong
Ninety percent of the world’s freshwater is locked up as ice in Antarctica and scientists are working to better understand what might happen with all that ice in a warming world.
Researchers from the Antarctic Research Centre at Victoria University of Wellington and from the University of Otago are studying the Kamb Ice Stream, an enormous river of ice that drains from West Antarctica and feeds the world’s largest floating ice shelf, the Ross Ice Shelf.
Scientists have discovered that ice streams turn on and off, stalling for decades and even hundreds of years before starting to move again. Huw Horgan, from Victoria University of Wellington, says that Kamb ice stream stalled about 170 years ago and researchers are investigating why.
The research is part of an Antarctic Science Platform project called Antarctic Ice Dynamics.
The 2019 research season took place on the Siple Coast, which is the grounding line of the West Antarctic Ice Sheet, where the ice meets the ocean and starts to float, becoming the Ross Ice Shelf. It is as far south as the ocean reaches anywhere in the world.
The Ross Ice Shelf meets the smooth annual sea ice at Cape Crozier on Ross Island. The cliffs mark the seaward edge of the largest ice shelf in the world, about the size of France. It is terrestrial ice which has flowed off the Antarctic continent and floats on the sea. The sea ice is frozen seawater. Photo: RNZ / Alison Ballance
In hot water
The researchers use a hot water drill to melt through 600-metres of ice, to reach the water and sea floor below.
Driller Darcy Mandeno, from Victoria University of Wellington, says the drill will take about 12 hours to make a 35 centimetre diameter hole, through which the researchers can lower various instruments to measure physical attributes of the water, as well as drill a short sediment core.
Extensive control systems and infrastructure are needed to run the hot water drill being used for ice research in Antarctica. Hedley Berge and Tim McPhee, from Victoria University of Wellington are monitoring the system. Photo: Darcy Mandeno / Antarctic Research Centre VUW
Hidden crevasses are an ever-present danger in Antarctica. Photo: CC BY 2.0 NASA Goddard/ Kelly Brunt
Crossing Antarctica
The first full traverse across Antarctica was made by Sir Vivian Fuchs. Sir Edmund Hillary and his Kiwi team famously drove Massey Fergusson tractors to meet Fuchs at the South Pole, as part of the Commonwealth Trans-Antarctic expedition.
Every year, the United States Antarctic programme drives three traverses from McMurdo Station to the South Pole, dragging sleds carrying fuel and supplies.
In 2017, the Antarctica New Zealand started its own traverses, dragging scientific equipment to remote field camps on the Ross Ice Shelf.
The seaward edge of the Ross Ice Shelf Edge, where thousands of small icebergs calve from the ice edge. Photo: Bethany Burton, U.S. Geological Survey. Public domain
Traverse navigator Daniel Price, a sea ice researcher at the University of Canterbury, selects safe routes for the traverse to follow. He uses satellite radar images to identify and plot large crevasses which must either be avoided or blown up to create a safe crossing.
Daniel says the most dangerous part of the South Pole traverse is a shear zone located just 40 kilometres from McMurdo. The zone contains multiple crevasses which need to be blown up with explosives and then filled with snow.
In late 2019, the New Zealand traverse took hot-water drilling equipment to the Siple coast area of the Ross ice shelf, which is where the Kamb ice stream is located. It was a 1100 kilometre journey.
‘Melting ice, rising seas’ team wins PM’s Science Prize
Huw and Darcy are part of the team that has just won the 2019 Prime Minister’s Science Prize.
Voices from Antarctica – listen to the full series
Voices from Antarctica 1: Ice Flight
Voices from Antarctica 2: Scott Base
Voices from Antarctica 3: Flags to physics
Voices from Antarctica 4: Best journey in the world
Voices from Antarctica 5: Waiting for Emperors
Voices from Antarctica 6: Seal songs
Voices from Antarctica 7: What the ice is saying
Voices from Antarctica 8: Under the ice
Our Changing World’s Antarctic collection
Listen to a wide range of stories recorded in and about Antarctica from our archives.
More than 90 percent of ice in Antarctica flows off the continent towards the sea via giant ice streams. A New Zealand research team is studying the Kamb ice stream which stalled about 150 years ago. Photo: AntarcticGlaciers.Org
