Henry Darwin Rogers Special Lecture

May 3, 2024 at - | LRSM Auditorium

Special Seminar

The Department of Earth & Environmental Science

University of Pennsylvania


Invites you to attend our annual

 Henry Darwin Rogers Special Lecture and Student Awards Ceremony

Friday, May 3rd  2:30 PM


LRSM Auditorium located in the Laboratory for Research on the Structure of Matter

3231 Walnut St, Philadelphia, PA 19104


"Slow Closure of Earth's Carbon Cycle"


Earth's carbon cycle inherits the complexity of biology, geology, and chemistry.  Yet somehow it expresses a mathematical structure: once carbon dioxide is reduced to organic carbon by photosynthesis, its oxidation back to CO2 by microbial respiration slows down at rates that are inversely proportional to its age.  Moreover, microbial populations themselves decrease as a power of age.  Timescales range from days to millions of years.  I show that a simple model of fluctuation-limited kinetics quantitatively predicts these and other observations.  The impact of these slow dynamics is profound: they preclude complete oxidation of organic carbon, thereby freeing molecular oxygen to accumulate in the atmosphere.



Dr. Daniel H. Rothman
Professor of Geophysics
Massachusetts Institute of Technology


Daniel H. Rothman is a Professor of Geophysics in the Department of Earth, Atmospheric, and Planetary Sciences at MIT.  He is co-founder and co-director of MIT's Lorenz Center, which is devoted to learning how climate works.  Rothman joined the MIT faculty in 1986, after receiving his AB in applied mathematics from Brown University and his PhD in geophysics from Stanford University. He has held visiting appointments at the University of Chicago, Ecole Normale Superieure, and Harvard's Radcliffe Institute for Advanced Study.

He is a Fellow of the American Physical Society and the American Geophysical Union, and the recipient of the 2016 Levi L. Conant Prize from the American Mathematical Society.


A lunch reception will precede the ceremony in the Hayden Hall building at 12:30 PM

Please RSVP at earth@sas.upenn.edu or (215) 898-5724