Paleo Slide Set: Low Latitude Ice Cores: High Resolution Records of Climatic Change and Variability 
in the Tropics and Subtropics
Removing drill apparatus.

The drill string is lowered into the core hole on a cable. When the drill bit cuts enough ice to fill 
the core sleeve, the drill apparatus is carefully pulled up and out of the core hole. The ice core is 
then carefully removed from the drill. The bubbles of gas in this section of core are ancient samples 
of the atmosphere preserved when firn(a transition material between snow and ice, snow becomes firn after one year) 
became glacial ice, locking gases into the ice fabric. While these gases have been analyzed at polar sites 
like Vostok and Greenland Summit, temperatures at Quelccaya are too high for effective preservation and analysis of CO2. 

Photo Credits:
Lonnie Thompson 
Byrd Polar Research Center, The Ohio State University