Read more about ice cores on our homepage of glaciology at the Department of Geophysics at the University of Copenhagen.

An ice core to bedrock

Formation of ice
Any new snow layer is gradually compressed into solid ice under the weight of succeeding layers. During the compression, samples of atmospheric air are trapped as tiny bubbles in the ice. 

Ancient atmospheres
may therefore be studied by analyzing the air in the bubbles. Other characteristics of past atmospheres, such as temperature, precipitation and storminess are revealed by studying the ice itself and its impurities. 

What is ice core research good for?
NGRIP aims at solving problems like these: 
What was the relationship between climate and greenhouse effect in the unpolluted atmosphere? 
How could the North Atlantic climate get 7°C warmer in 50 years at the end of the last glaciation? 
Could it happen again? 
What was the duration of the warm period prior to our own, and how will our own warm period end? 
Are natural climate changes predictable? Or do they occur quite randomly? 
Are man made climate changes predictable? 

The drill

Drilling progress
In 1996, the drill reached 350 m. The following year, the drilling continued in routine until a depth of 1371 m, where the drill got stuck, partly due to the hole liquid used. Recovery attempts in 1998 were unsuccessful, and drilling restarted in 1999, where a depth of 1750 m was reached. 

Associated projects

Monitoring of the iceflow
In collaboration with the "Danish Survey and Cadastre" (KMS) and the "Danish Center for Remote Sensing" at the Technical University of Copenhagen the ice surface is being monitored very accurately. This is part of the ECOGIS project, and amongst others it serves to determine the local ice flow.

Automatic weather stations
As part of a collaboration between GEUS and the US PARCA project two automatic weather stations are installed at NGRIP. This provides some of the sparse meteorological measurements on the ice sheet.

GLATIS
The breakup of Europe and North America along the central East Greenland coast  60 Ma years ago was influenced by an anonymously hot area in the earth?s mantle. Where and when this Icelandic Hotspot  or mantle plume of hot material from deep in the earth  came to be is under discussion, and information about structures and velocity distributions in the crust and upper mantle can help.  Diamond finds worldwide are connected to Arkaean cratons, where the temperature and pressure conditions are favorable for  the formation of diamonds. Knowledge of crust and upper mantle 
conditions are important for an evaluation of the diamond potential in Greenland. The creation of mantle material under the cratons is an intensively debated topic, where new finds and analysis of samples brought 
up to the surface (zenoliths) play an important role. The ability to connect these samples to the effect of the Iceland Hotspot on the lithosphere can teach us about the formation and subsequent modification of 
the lithosphere and upper mantle under the cratons.
   The nature of the crust and upper mantle in Greenland is very poorly known, as practically all investigations have taken place in the coastal regions, where the Greenland craton is influenced by later processes.
  We will in the GLATIS project utilize new broad-band seismological stations, both the 4 permanent stations as well as 16 temporary stations, placed all over the Greenland craton for periods from a few months to a few years. Signals from teleseismic earthquake propagate in the mantle on their way to the Greenland stations, and carry information about the deep subsurface structures of the crust and upper mantle. We use several different methods focussing on different aspects of the data, and by combining the results we can construct the best possible model of  the structures underneath Greenland.
The GLATIS project involves researchers from KMS, DLC, KU, the Greenland Bureau of Minerals and Petroleum and the Arctic Station.

Radar Surveys
The NGRIP area has been surveyed intensively by ice penetrating radars. First, in 1994 and 1995, NASA and Kansas University using the NASA P3 aeroplane made a set of measurements along the ridge all the way to Summit at 72N. These measurements were the basis for the selection of the NGRIP site. Later, the Alfred Wegener Institute used their Dornier aeroplane to make a detailed map of the bedrock 180 km from NGRIP. These measurements confirmed, that NGRIP was indeed the optimal site for this program. Finally, Kansas Univeristy made a traverse from NGRIP and 70 km upstream, measuring the bedrock and internal layers with high precision. Also, Kansas University tested several modern radars for more shallow depths. Finally, Italy has tested a modern radar prior to its deployment to Antarctica. 
The NGRIP site is ideal for testing ice penetrating radars. The logistics are in place, and the ice is cold. There are no crevasses, and regular contact to the base in Kangerlussuaq.