ESS200A
Prof.
Jin-Yi Yu
The Last Glacial
Maximum (21,000 Years Ago)
qSeasonal insolation
levels 21,000 years ago were
nearly identical to those
today.
qThe only factors that
can explain the colder and
drier glacial maximum
climate 21,000 years ago are:
(1) the large ice sheets
(2) the lower values of greenhouse gases.
(from
Earth’s Climate: Past and Future)