An international science team involving the University of Colorado at Boulder that is working on the North Greenland Eemian Ice Drilling project (NEEM) hit bedrock July 27 after two summers of work, drilling down more than 1.5 miles in an effort to help assess the risks of abrupt future climate change on Earth. Led by Denmark and the United States, the team recovered ice from the Eemian interglacial period from about 115,000 to 130,000 years ago, a time when temperatures were 3.6 to 5.4 degrees Fahrenheit above today's temperatures. During the Eemian -- the most recent interglacial period on Earth -- there was substantially less ice on Greenland, and sea levels were more than 15 feet higher than today.
INSTAAR fellow Jim White, the lead U.S. investigator on the project, said the new ice cores will more accurately portray past changes in temperatures and greenhouse gas concentrations in the Eemian, making it the best analogue for future climate change on Earth. The cores samples are being studied in detail using a suite of measurements, including stable water isotopes that reveal information about temperature and moisture changes back in time. As part of the project, the researchers want to determine how much smaller the Greenland ice sheet was 120,000 years ago when the temperatures were higher than present, as well as how much and how fast the Greenland ice sheet contributed to sea level.
The 300-person NEEM team includes postdoctoral researcher Vasilii Petrenko and doctoral student Tyler Jones.