A 14-person staff on a €13 million European mission will head to the East Antarctica ice sheet later this 12 months, to start drilling an ice core a number of kilometres deep. Researchers will use the bubbles of carbon dioxide and different gases trapped inside ice cores to supply a window into Earth’s previous local weather.
Particulars of the “Past EPICA” mission – which hopes to seek out ice courting again 1.5 million years – had been introduced this week on the European Geosciences Union Convention in Vienna, Austria.
Up to now, the oldest ice ever to have been drilled was a core that dates again 800,000 years, unearthed 15 years in the past. However that leaves a spot in our information of a key interval when Earth’s local weather shifted, often known as the mid-Pleistocene transition.
This era noticed the world change from a rhythm of switching between heat and chilly phases each 40,000 years, to a cycle each 100,000 years.
There are competing theories for why this occurred, and the brand new expedition hopes to supply the proof to clarify it.
“We have to perceive why now we have this alteration 900,000 years in the past, and why we stay in a 100,000-year [cycle] world. With out [doing] that we can’t say we actually perceive our present local weather programs,” says Barbara Stenni of Ca’ Foscari College of Venice, Italy.
The ice can even present essential new knowledge to enhance modelling of how our planet’s local weather will evolve sooner or later, she provides.
The staff have spent the previous three years utilizing radar to look under the ice, trying to find the place friendliest for drilling and more than likely to yield ice that’s sufficiently old. Their work instructed a web site often known as Little Dome C, 40 kilometres from the Concordia station in East Antarctica.
With temperatures of -50°C, drilling in such a hostile setting shall be powerful. “The circumstances are extremely harsh,” says Carlo Barbante of Ca’ Foscari College of Venice. “There are lots of issues that may go improper in an expedition like that.”
For instance, the staff may find yourself with no gasoline if there are delays transporting it from Australia. The drilling bit may get caught within the ice and require a brand new gap to be drilled – as occurred to the researchers who drilled the 800,000-year-old ice core.
Time is crucial. There’s solely a two-month window annually when the Antarctic climate will permit individuals to work, so even with drilling across the clock, the mission will nonetheless take years.
The staff count on to drill down 2.7 kilometres. However as a result of the oldest layers of ice are compressed by the burden of the newer ones urgent down from above, researchers are unlikely to have the ability to peer past 800,000 years till the final 200 to 300 metres of ice. That ought to occur by 2024.
Whereas researchers are assured they may discover ice sufficiently old, there isn’t a assure it should return so far as they need, or that the layers shall be stratified clearly sufficient to tell apart between them.
“We’ve a really giant probability to get 1.5 million years, a greater than 90 per cent probability,” says Catherine Ritz of the Institute for Geosciences and Environmental Analysis in Grenoble, France.
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