PHYSICAL MATHEMATICS SEMINAR



TITLE:		DYNAMICS OF THE ANCIENT CARBON CYCLE



SPEAKER:	DANIEL H. ROTHMAN
		Earth, Atmospheric and Planetary Sciences 
		Massachusetts Institute of Technology



ABSTRACT:

Long-term changes in the Earth's carbon cycle are encoded in the isotopic composition 
of carbon buried in ancient sediments.  Extraordinarily large fluctuations in this signal 
occur in the geologic era preceding the first great diversification of animal life.  Analysis 
of the geochemical records and construction of a simple model indicate that these large 
fluctuations also precede a major dynamical transition, from a carbon cycle evolving 
dynamically, far from steady state, to a carbon cycle evolving quasistatically, from one 
steady state to another.  We suggest that this transition reflects a fundamental reorganization 
of the Earth's biogeochemical cycles.



TUESDAY, OCTOBER 28, 2003, 2:30 pm, Building 2, Room 338

Refreshments will be served at 3:30 PM in Room 2-349


                       
Massachusetts Institute of Technology, Department of Mathematics, Cambridge, MA  02139