ESS101C
Prof.
Jin-Yi Yu
Orbital-Scale Climate Change
qChanges in solar heating driven by
changes in Earth’s orbit are the major cause of cyclic climate changes
over time scales of tens to hundreds of thousands
of years (23k years, 41k years, and 100k years)
.
qEarth’s orbit and its cyclic variations: tilt
variations, eccentricity variations, and precession of the orbit.
qHow do orbital variations drive the strength of
tropical monsoons?
qHow do orbital variations control the size of
northern hemisphere ice sheets?
qWhat controls orbital-scale fluctuations of
atmospheric greenhouse gases?
qWhat is the origin of the 100,000-year climate
cycle of the last 0.9 Myr (ice sheets melt rapidly every 100,000 years)?
Why?
(from Earth’s Climate: Past and Future)