qThe pace of the 100,000-year
variations in ice sheet size is set by the external forcing from the eccentricity orbital cycle.
qThe amplitude of the
100,000-year cycle depends in part on the internal interactions of the climate system.
qThe large ice sheets themselves
produced internal
interactions within the climate system that hastened their own
destruction every 100,000 years.
qThe possible positive feedbacks
to accelerate ice sheet
melting include: rising CO2 level during deglaciations, the delayed in
bedrock rebound provided warmer temperatures in the depressed land surface for fast ice
melting, and other ice-controlled processes in wind, sea level, and deep ocean circulation.