It's been four months since the ice core scientist has seen the 419 one-metre tubes of ice.

In that time, they’ve been packaged into specially designed freezer bags and journeyed from a remote drill site in inland Antarctica, travelling by light aeroplane, oversnow vehicle, barge, icebreaker and truck, to Hobart.

The puddle of water at the door of the refrigerated shipping container where they are now stored turns out to be from the rain.

Inside, Curran finds the cores just as he last saw them, frozen.

Ice, or more specially the ice that has formed in places like Antarctica from snow accumulating over time, is a fastidious record keeper of the world’s past climate.

Scientists drill cores to reveal traces of what was in the Earth’s atmosphere at the time it was desposited with snow.

"Drilling ice cores is like taking a breath from the Earth, says Curran.

His crew of Australian, French, Chinese, Danish and US scientists extracted ice that dates back 2000 years.

But drilling these time capsules is a long and expensive endeavour. Curran, 44, has spent almost 10 years as the scientific leader of this project, which still has a long way to run. From next week sections of ice will be shipped to laboratories around the world for extensive analysis.

VIDEO: Antarctic ice a labour of love  

While many things store a memory of the Earth’s past conditions – tree rings, peat bogs, ocean sediments and fossil pollen – the value of ice cores is they offer a continuous record over time scales as recent as a few decades to as far back as several 100,000 years.

Past cores have provided some of the most reliable records of the carbon dioxide increase in the atmosphere and the parallel rise in global temperatures since the Industrial Revolution.

But improvements in the technology used to analyse cores means the ice drilled this summer will be probed not just for temperature and C02 concentrations, but for information on storm events, solar and volcanic activity, industrial pollutants and sea ice extent.

"It'll be the best record in terms of the amount of information we get at once so we can really get an understanding of how things interact," says Curran.

Sharon Labbuda had never seen an ice core before last summer. As field leader her job was to run the remote camp where the drilling would take place.

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The site, known as Aurora Basin North, was selected because only one other core had been collected in that part of East Antarctica. It also received regular snowfall, which meant the scientists could extract enough data from the ice to show changes in the past environment from year to year without having to dig too deep for it. But the site's snow conditions were both a blessing and a curse.

Too much snow meant the trip had to be postponed in 2008 because the light aeroplanes could not land.

To reach the site the Australians enlisted the help of a French research station to traverse the equipment across the continent instead of transporting it by plane. Antarctica's isolation and harsh conditions often encourages countries to work together.

Labbuda, accompanied by two other Australians and a team of French workers, used tractors and graders to drag 26 tonnes of food, equipment and supplies more than 1300 kilometres from the French research base Dumont D'Urville to Aurora Basin.

‘‘It was hard work, we’d get up at 6 o’clock, get the machines ready by 8am and then drive until 8:30pm with an hour break for lunch,’’ says Labbuda, who is also a qualified diesel mechanic.

When the group made it to the site after 14 days they had to set up the most of the camp, including the drilling and processing tent, the kitchen tent and about 20 sleeping tents. In minus 30 degrees and 20-knot winds they also had to groom a two-kilometre-long skiway.

‘‘Putting up tents with all the little clips was really difficult because you didn’t want to take your gloves off,’’ says Labbuda. ‘‘You had to keep telling yourself ‘we just have to keep doing this’,’’ she says.

With the camp ready about 15 scientists and support staff could fly in on small planes, staggered over several weeks in late December due to bad flying weather.

Curran says it was an amazing feeling when he finally put his boots on the ice he would soon be drilling.

"At that point I was about 50 per cent sure [the project would be] a success," he says.

Over the next month the team extracted three ice cores, drilling to just over 100 metres for two cores and down to 303 metres for the main 2000-year-old core, using a specialised drill brought from Denmark that could cope with the frigid temperatures at depth.

"When we got out that first ice core it was an exceptional feeling. After that we knew we just had to repeat it 300 times and we'd be there," says Curran, who would drill cores in two to three-hour shifts before getting so cold that he would have to break for a cup of tea.

As each one-metre section of ice was pulled out its depth was recorded, an essential step for determining its age.

"If the ice is not logged you might as well use it in your whisky because it's useless," says JP Steffensen, one of three Danish ice core scientists involved in the project.

In the field the cores were stored in snow pits to keep them cold and protect them from the sun's radiation until they could be transported out of the camp.

With the hardest part now over and the cores safely back in Australia, Curran is keen to get their processing under way.

Next week sections of the 116-metre core will be flown to Germany where a specialised x-ray machine will measure its density, a useful way to interpret the rate the snow accumulated over time.

It will then be sent to Curtin University in Western Australia where it will be partially dated and analysed for a range of compounds before being chopped into one-year sections and measured for beryllium 10, a proxy measure of the sun's activity.

"That'll give us an annual record of solar activity over the past about 800 years," Curran says.

On the main 303-metre core the team has already measured its levels of oxygen-18, an isotope that is used to determine the temperature at the time the ice deposited as snow.

Getting an accurate temperature record is the cornerstone of ice core analysis as far as bodies like the Intergovernmental Panel on Climate Change are concerned.

Measuring the level of greenhouse gases such as carbon dioxide is also why ice cores are considered so valuable. One of the clearest records of the rise in C02 comes from cores drilled on the coast of Antarctica, at a place called Law Dome.

David Etheridge, a principal research scientist with CSIRO who was part of the Australian team that drilled the cores in the 1980s, says analysis of the air pockets trapped inside the ice gives a snapshot of greenhouse gas levels across the past 2000 years. The evidence is remarkable.

After centuries of relative stability, CO2 rose from about 280 parts per million to nearly 400ppm, with the surge coinciding with the start of the Industrial Revolution. The rise also closely mirrors the world's use of fossil fuels and large-scale deforestation.

Etheridge says the pristine polar ice contains an isotope of carbon – "a fingerprint of its origin" – that reveals how much of the ice's trapped CO2 can be attributed to fossil fuels.

A similar type of analysis will also be done on the Aurora Basin cores.

In July thin sticks of ice from the main core will be sent to the Desert Research Institute in Nevada where they will be melted into water and scrutinised for a range of chemicals from salt to plutonium, which circulated the atmosphere as particles or gases before depositing on the ice.

Joe McConnell, the institute's director, says his state-of-the-art analytical system can detect dust that has travelled to Antarctica from other continents, emissions from forest fires, volcanic eruptions, black carbon from industrial activities and even heavy metal pollutants like lead.

In Hobart Curran's laboratory will begin, among other things, studying sea salt concentrations, sulphate from volcanoes and a chemical called MSA, which can be used to estimate the amount of sea ice in Antarctica.

‘‘This project has taken up the last nine years of my life, and it’ll probably take up the next nine,’’ he says.

Nicky Phillips travelled to Antarctica in December as part of the Australian Antarctic Division's media program.