PARIS: Imagine you are Sherlock Holmes bent on solving a mystery but the evidence is starting to crumble and eventually you will be left with worthless dust. This is the worry which haunts ice scientists delving into Earth’s threatened glaciers. Deep inside them, the slumbering ice slabs hold information about Earth’s climate past, and pointers for the future. The frozen archive is formed from compacted layers snow which fell hundreds, thousands or even hundreds of thousands of years ago. Learning more about the past through examining the glaciers could help us predict how our planet will respond when global warming kicks into higher gear-just decades from now, if predictions are right.
Only a tiny amount of this glacial material has ever been extracted and examined. And as temperatures rise, the fringes of many glaciers are softening to mush, threatening the survival of this precious testament. “We are the only scientific community working on climate his- tory whose research material is disappearing,” lamented Jerome Chappellaz at the Laboratory for Glaciology and the Geophysics of the Environment in Grenoble, south- eastern France.
“It is time to do something-we have to act now, while the glaciers are still a useable source.” That “something” is a new scheme to build a vault for ice cores extracted by scientists from the deep chill of Antarctica. About 50- 130 millimeters (two to five inches) wide, in sections between one to six meters (a yard to 20 feet) long, ice cores are glaciology’s mainstay.
Within them are telltale bubbles of gas, notably the greenhouse-gas carbon dioxide (CO2). By studying them, “past eras can be reconstructed, showing how and why climate changed, and how it might change in the future,” says the US National Snow and Ice Data Center. The deepest-ever core, drilled in Antarctica, is 3,270 meters long, and revealed the world has gone through eight ice ages over about 800,000 years. These cycles, which pro- foundly affect life on our planet, generally move in lock- step with greenhouse gases. Until the start of the Industrial Revolution in the mid-18th century, these heat-trapping gases had natural causes. Today, the relentless burning of coal, gas and oil has taken carbon out of the ground and placed it in the atmosphere-con- centrations are now higher than at any time in the ice- core record.