Template:POTD/2007-08-08
A section of the GISP2 ice core (view the entire image) from 1837 meters (6027 feet) deep in which annual layers of ice are clearly visible (38 years are represented in the entire image). The appearance of layers results from differences in the size of snow crystals deposited in winter versus summer and resulting variations in the abundance and size of air bubbles trapped in the ice.Photo credit: National Ice Core Laboratory
