IGPP is pleased to invite you to join its Fall 2022 Seminar Series presentation featuring UC Berkeley's Harriet Lau. Dr. Lau's talk, "Evolving Solid Earth Dynamics Across the Mid Pleistocene Transition" will be shared in person, in the Munk Conference Room at IGPP and available via Zoom: https://ucsd.zoom.us/j/93560901990?pwd=elQ3VDhTMGUxYndLdEQxNjFZekdJdz09 (Password: GP_seminar) on Tuesday, October 18, 2022, starting at 12:00pm.
Time: 12:00 pm, Pacific Time
Location: Revelle 4000 (presenter will be on zoom)
Note: This meeting will be recorded. Please make sure that you are comfortable with this before registering.
Milankovitch cycles – orbital modulations in Earth’s insolation – are thought to pace ice ages over the last 2.6 million years, with dominant periods associated with changes in precession (∼20,000 years) and obliquity (∼40,000 years). While Milankovitch cycles have not changed over tens of millions of years, Earth’s climatic response has. In particular, the Mid Pleistocene Transition (MPT), ∼1 million years ago, is defined by an enigmatic shift between ice ages paced every ∼40,000 to ∼100,000 years. We explore solid Earth feedbacks (i.e., crustal rebound/subsidence) on the ice age system using a climate model that accounts for variation in the timescale of crustal deformation associated with changes to the length-scale of ice ages and duration of ice loading. We demonstrate that the impact of the feedback mechanism is significantly larger in the late Pleistocene relative to the early Pleistocene, and hypothesize that this sensitivity played a crucial role in driving the MPT.