International Ice Core Team Hits Bedrock in Greenland
Next to Antarctica, Greenland is home to the largest ice sheet on Earth. Scientists in the frigid north of this enormous island have achieved quite an accomplishment by drilling all the way to the bedrock under the ice. On Tuesday, July 27, 2010 at the North Greenland Eemian Ice Drilling site (NEEM), the team completed their drilling to a depth of 2537.36 meters (1.58 miles).
The Eemian is an interglacial period, 115,000 to 130,000 years ago, when global temperatures were 2-3 degrees Celsius (3-5 F) higher than they are today. Sea levels were five meters higher, but ice still existed on Greenland. The researchers believe this may useful for predictions of future climates.
The NEEM project has involved over 300 ice core scientists from 14 nations including Belgium, Canada, China, Denmark, France, Germany, Iceland, Japan, Korea, The Netherlands, Switzerland, Sweden, the United Kingdom of Great Britain, and the United States of America. It was headed by Project Leader Dorthe Dahl-Jensen, Professor at the Niels Bohr Institute at the University of Copenhagen. The project took over five years to complete.
The team has brought up ice near the bedrock that has not seen the light of day for hundreds of thousands of years. Clues such as DNA or pollen embedded in the ice can give the researchers an idea of what existed on Greenland before it became covered by ice over three million years ago.
Dr. Eric Wolff of the British Antarctic Survey said "It is a tremendous achievement to have collected ice right down to the rock, 2.5 km below the ice surface. This core should really help us to understand how the Arctic ice responded in the past at a time when it was warmer than today."
Such a tremendously long core is like having a book of the history of the world. The trick is learning how to read it. For example, variations in climate can be detected by a host of high-tech equipment that can analyze a number of factors. The stable water isotopes found within the core can indicate moisture sources going back in time. Greenhouse gases trapped in the ice can be read by state of the art laser instruments. Also, biological content can be analyzed to determine what life existed there and at what point in time, as well as their annual variability. Other impressive tools used for analysis include online impurity measurements and advanced studies of ice crystals.
The purpose of the study was to gather more information on the warmer Eemian interglacial climate and use that to help predict the warming climate in Earth's future. The team hopes to figure out how reduced the Greenland ice sheet was during that period and how much its melting contributed to sea level rise.
Climate science is perhaps the most complicated of all sciences due to the myriad of factors involved. The work done by the NEEM team will help bring us one step closer towards a more accurate model to be used by today's and future generations.
North Greenland Eemian Ice Drilling website: http://neem.nbi.ku.dk/