EXCITING NEWS from the North Eemian Ice Drilling (NEEM) project!
According to reports from the NEEM field camp, they are now (as of July 18, 2010) at 2,491 meters depth, which means they are a mere ~70 meters from bedrock. More importantly, it is very likely that the NEEM project has reached ice from the Eemian period. This is based on high oxygen isotope values, large ice crystals and high ECM values in the ice that they have been drilling.
According to the June 29, 2010 NEEM field diary, "The freshly drilled cores gives a hint about in which climate the snow was deposited. In cold climates, such as a glacial period, the ice contains high concentrations of dust and other impurities which are often seen in the ice as 'cloudy bands'. The freshly drilled ice is completely transparent, indicating that we are now drilling the Eemian interglacial ice. Another climate proxy is the ice crystal size, which is related to both the impurity content and the temperature history of the ice. In the ice drilled over the last days we've occasionally seen ice crystals that are several cm across, which is also indicating that we are drilling in warm low-impurity ice. The next climate indicator we get [is] from the DEP and ECM measurements, which are measures of the dielectric properties and the conductivity of the ice, respectively. Comparison of those profiles to the corresponding profiles from the NGRIP ice core shows that we are now in the Eemian. Probably the most robust climate indicator we get [is] from the water isotopic composition of the ice which is measured in camp some days after the core is drilled."
NEEM is an international research effort involving 14 nations and led by the University of Copenhagen in Denmark. The University of Colorado at Boulder is the lead U.S. institution. The goal of the project is to retrieve ice from the last interglacial period, called the Eemian, that ended about 120,000 years ago. In Greenland, the Eemian was several degrees Celsius warmer than today, and is our best analog for a potentially warmer future climate. For more information about NEEM, read the NSF press release (International Greenland Ice Coring Effort Sets New Drilling Record in 2009) featured in the Fall 2009 issue of In-Depth).
For the latest information on how the NEEM field season is going, be sure to read the field diaries at: http://neem.nbi.ku.dk/field_diaries/