Climate Change and Ice Caps: Is Greenland's ice cap breaking apart due to global warming?

Principal Investigator: J.A. Rial
Geological Sciences

An important part of this research is aimed at understanding the mechanisms that have made the climate system undergo very large, hemispheric, and abrupt changes in pre-historical times, well before human intervention. To understand the climate tomorrow we must understand its history, and to predict any consequences of human activity on the climate it is important to know the extent of natural variability, and climate sensitivity. For many years conventional wisdom has dictated that the ice caps of the planet are too sluggish, their thermal inertia too great to abruptly respond to the changes imposed by anthropogenic global warming.

The photos show several stages in the deployment of the seismic stations, and scenes from the glacier.

Sponsored by NSF and in collaboration with CIRES (U. Colorado, Boulder), this research team started an unprecedented climate change monitoring project called SMOGIS (Seismic Monitoring of Greenland's Ice Sheet) in western Greenland. During May 2006 they deployed an array of seismic stations on the ice sheet to basically listen to it as it breaks -and fragments- under the forcing of global warming. The idea is that areas of the ice sheet within 100-200km of the ocean act as the buttresses of the giant cathedral the Greenland ice cap is. If they fail, the entire structure may collapse, sending most of the ice crashing down into the ocean (this is actually happening at a local scale in western Greenland's Jakobshavn glacier, the fastest moving outlet glacier in the world), which would increase mean sea level by 21 meters globally. The team is beginning to analyze the seismic data (ice-quakes) recorded by the seismic array. Indications are that the amount and intensity of cracking of the ice has increased due to the warming season, as expected. It will however take a few years for the experiment to detect any accelerating cracking.