ESS101C
Prof.
Jin-Yi Yu
Ice Sheet Lags Behind Summer Insolation Forcing
qUnder the most favorable
condition (ice
accumulates 0.3 meters each year), a full-size ice sheet 3000 meters thick would take 10,000 years to form.
qAt the
41,000-year cycle of orbital tilt, ice sheets lag behind changes in summer insolation by about 10,000 years.
qAt the
23,000-year cycle of orbital precession, ice sheet lags behind summer insolation by about 6,000
years.
qThe lag
times are both about one quarter of the periods of the cycles.
(from Earth’s Climate: Past and Future)