With a sudden reward of mud at their feet, researchers at the EGRIP research station had successfully made it through the 2670-meter ice sheet last week after seven years of drilling. In doing so, the research group met their ultimate goal of drilling all the way through the ice and to the bedrock below.
“This is the first time that a deep ice core has been drilled through an ice stream, so it will be extremely exciting to analyse the material, which has much to tell us about how our planet’s climate has changed over the past 120,000 years. But we need to wrap up our work here first,” says Professor Dorthe Dahl-Jensen of the University of Copenhagen’s Niels Bohr Institute, who leads research at EGRIP.
The mud, which had not seen the light of day for roughly a million years, was only briefly exposed to sunlight, as white light can damage ice core material. Instead, the core was retrieved in red light and immediately packed away, like a Christmas present that will need to remain unopened until some special day down the road.
“Though it was tempting to take a closer look, we quickly sealed the ice core, kept it frozen and sent it to Kangerlussuaq Airport, where it is now waiting for a flight to Denmark,” says Dorthe Dahl-Jensen.
Results could change climate models
Despite the quick packaging and send off, the drilling has already delivered the scientists research “gold”.
“The results are exceptional. The ice stream flows like a river of ice that tears itself free of the surrounding slow-flowing ice sheet. We can see that the entire 2670-meter-thick mass of ice flows like a block at a speed of 58 meters per year. This will change climate models because it redefines our basic understanding of how ice moves,” explains Dorthe Dahl-Jensen, who continues:
“The block of ice floats on a layer of wet mud. It seems to act as a kind of layer of quicksand that allows the ice block to flow undisturbed across the bedrock. Near the bottom of the ice sheet, we find rocks and sand embedded in the ice. The measurements also show that the ice is melting at the bottom,” she says.
Towards the base, the ice is more than 120,000 years old and dates bac
