Researchers in Antarctica say they've captured a climate change "snapshot" by successfully drilling into the continent's ice cover to retrieve an ice core going back 2,000 years.
An international team of scientists from the United States, Australia, Germany, France, Denmark and China says the success of their Aurora Basin North project could be a step toward a "holy grail" of climate science, recovery of a core containing ice that's a million years old.
Drilling into some of Antarctica's thickest ice, in a region where it covers the continent in a sheet almost two miles thick, should yield the most precise record to date of the past climate of the area, the researchers say.
That data will come from analyzing atmospheric gases, chemical elements and particles contained in snow that fell on the region and was compacted into ice over thousands of years.
"Using a variety of scientific tests on each core, we'll be able to obtain information about the temperature under which the ice formed, storm events, solar and volcanic activity, sea ice extent, and the concentration of different atmospheric gases over time," project leader Mark Curran, a glaciologist with the Australian Antarctic Division, says.
Operating in temperatures of 22 degrees below zero Fahrenheit and using a Danish-built drill, the researchers were able to extract an ice core almost a thousand feet in length, containing a record of thousands of years of climate events.
Sections of the cores are being distributed to ice core laboratories around the world.
"There are only a handful of records with comparable resolution that extend to 2,000 years from the whole of Antarctica, and this is only the second one from this sector of East Antarctica," Curran said.
The scientists also used a smaller drill to recover cores of 380 feet and 330 feet.
"These shorter cores will provide extra ice for large volume chemical analyses," Curran says.
The success of the project has the scientists considering an expedition with the more ambitious goal of collecting a core containing ice one million years old.
Such a core would yield clues to the reasons behind a significant shift of the frequency at which ice ages occurred, a shift that happened around 800,000 years ago, Curran said.