17. august 2009

Ice core drilling sets new world record

After 110 days the field season is reaching the end at the NEEM ice camp on the Greenland Ice Sheet. The season has been a tremendous success with the ice core drilling and processing of ice from the surface to 1757.84 m depth.


The deep ice core drilling to the depth 1757.84 m
is a new world record for deep ice core drilling in a
100 day long summer season. Professor Dorthe
Dahl Jensen shows the deepest ice core from this
years drilling.



The ice cores at this depth are 38.500 years old from the cold glacial climate period. This period of time was dominated by very abrupt climate changes with rises in average temperature of 10-15 deg C over Greenland in few decades.

Ambitious scientific project
The ambitious scientific program of the NEEM project involves science groups from 14 participating nations. The abrupt changes are studied in detail by a suite of different measurements, including the stable water isotopes telling about the temperature changes and moisture sources back in time, greenhouse gasses trapped in the ice and biological content to improve our understanding of the natural behavior, feedbacks of the carbon and the biogenic cycle and very detailed chemical measurements resolving the annual variations of the climate. 

The North Greenland Eemian Ice Drilling - NEEM - is
an international ice core research project aimed at
retrieving an ice core from North-West Greenland
(camp position 77.45°N 51.06°W) reaching back
through the previous interglacial, the Eemian.

The deep ice core drilling to the depth 1757.84 m is a new world record for deep ice core drilling in a 100 day long summer season beating the previous record from the international NorthGRIP ice core project 1996-2004. We are especially proud of this record because the NEEM ice core is drilled in a new environmental friendly drill fluid developed by the NEEM team.

Global warming in the past
The ice at NEEM is believed to be 2545 m thick and we hope to reach bedrock in 2010 or 2011. The main aim of the project is to drill an ice core through the ice from the warm Eemian climate period, 120.000 to 130.000 years ago. This climatically warm period occurred between the last two ice ages, and it was 5 deg C warmer in Greenland at that time.


The season has been a tremendous success with the ice core drilling and processing of ice from
the surface to 1757.84 m depth.

"The results from the ice core will tell us about this climate and allow us assess the risks of future abrupt climate changes", Professor Dorthe Dahl Jensen explains. Studies of the Eemian climate and the evolution of the Greenland ice sheet during this period will be valuable as an analog to the warming expected in AD 2100, and the reachers expect to achieve ice from the Eemian period next year during the 2010 summer season.

The progress in the drilling at NEEM can be followed in the dairy on  https://www.neem.nbi.ku.dk/