The mission to unlock the secrets of Antarctica's deep, old ice will be a major feature of a week-long climate science conference beginning in Hobart today.
About 200 scientists from 22 countries are in Tasmania for the International Partnerships in Ice Core Sciences conference, hosted by the Australian Antarctic Division and the Antarctic Climate and Ecosystems Cooperative Research Centre.
While finding million-year-old ice is the holy grail of ice core research, the present focus will be on studying preliminary results from an Australian-led drilling expedition in 2013 and 2014.
Conference chairman Dr Tas van Ommen said the research was conducted in the Aurora Basin, a pocket of the Antarctic previously unexplored.
"It's about halfway between a very long ice core record that was drilled inland by the Europeans and a record we had at the coast," Dr van Ommen said.
"We wanted to find out how the climate changes as you go through that region.
The key result is proving that the carbon dioxide record of the last 200 years is completely unusual in comparison to the previous 800,000.
Professor Eric Wolff, Cambridge University
"For the first time, we're able to see there's quite a strong relationship between the temperatures over the last 2,000 years, at the coast and inland.
"That's quite an important finding."
Dr van Ommen said deep ice was a strong link in understanding Australia's climate and environmental changes.
"Things that are really important for the Australian climate, that control bushfires, like El Nino, and rainfall that comes from the Southern Ocean — all leave signatures in the ice cores," he said.
"The ice is a fantastic recorder of many different things in the climate and environment."
Professor Eric Wolff from Cambridge University played a significant part in charting the world's oldest known ice core, an 800,000-year-old sample taken from the Dome C area on the Antarctic Plateau.
"The key result is proving that the carbon dioxide record of the last 200 years is completely unusual in comparison to the previous 800,000, and what we've done to the atmosphere in the last 200 years is really something new," he said.
"We want now to get to even older ice, and go back beyond the million years."
Professor Wolff said the million-year figure was not just a number — it represented a crucial point in climate history.
"We know that records from marine sediments (show that) the way the climate worked before a million years (ago) was different to today," he said.
"We need to go through that transition, and in doing so it will tell us a lot about how carbon dioxide gets into and is removed from the atmosphere, which is important to understanding how present climate changes are going to play out in the long term."
Professor Wolff said one of the difficulties in locating million-year-old ice was the presence of hot rocks under the earth's surface which melted the deeper layers.
He said it was hoped a suitable site could be found and drilling begun by the year 2020.
Oregon State University Professor of earth, ocean and atmospheric sciences Ed Brook is co-chairing the event.
"We're building a very sophisticated drilling rig that is designed to drill through the Antarctic ice sheet in two weeks, and collect samples right at the bottom and drill into rocks below the ice," he said.
"The idea is to find the promising locations where we think there might be million-year-old ice, and sample those quickly.
"We won't be able to collect an entire ice core, but we will be able to collect ice from the bottom to check if we have the right spot and that would lead to large drilling projects after that."
International scientist 'concerned' for CSIRO
Professor Brooks said looming job cuts at the CSIRO were "definitely a talking point among international scientists."
"I personally study the greenhouse gases and ice cores and am very aware of the fundamental work studying both the history of the atmosphere and the current state of the atmosphere that is done at CSIRO," he said.
"I'm certainly concerned about cuts because particularly the monitoring of the atmosphere internationally is a very important job.
"There are concerns about potential cuts to such things from time to time in other countries, and I think as an international community it's very, very important for us to continue that monitoring."
Dr van Ommen said he could not comment directly about the cuts.
"What I can say [though] is the CSIRO have played a really important part in the national effort of ice core work," he said.
"In fact, the records we get from ice cores that show changes in atmospheric composition is work that's been lead by the CSIRO, and it's been enormously valuable.
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