Ice core Drilling Through the Greenland Ice Sheet (image) University of Copenhagen Share Print E-Mail Caption The ice is approximately 3 km thick in central Greenland and by analyzing every single annual layer in the kilometers-long ice cores researchers can get detailed information about the climate of the past. Credit Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen. Usage Restrictions Credit: Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.