ClimaTea Journal Club

Speaker: Judy Pu

Judy will lead the discussion on the Snowball Earth climate dynamics and Cryogenian and she lead us through the following key points:

• Geological evidence shows that ice from polar regions reached equatorial latitudes at least twice in Earth history during the Cryogenian Period (720-635 Ma).
• High-precision geochronology, paleomagnetism, and climate modeling support globally synchronous deglaciation for both snowball periods, but onset age and duration of the later Marinoan snowball Earth remain unclear.
• The snowball Earth periods were times of dynamic glaciers and ice sheets in a cold and dry climate state, with possible reversal of the annual mean tropical atmospheric circulation.
• Trigger mechanisms and reasons for the drastic difference in duration between the two Cryogenian snowball Earth events are still uncertain.