Thiemens, Mark
Atmospheric chemistry: physical chemistry of isotope effects; solar system formation

Contact Information
Distinguished Professor of Chemistry and Biochemistry
Chancellors Associates Chair

Office: Urey Hall Addn 3020D
Phone: 858-534-6732
Group: View group members
1977 Ph.D., Florida State University
1972 B.S., University of Miami
Awards and Academic Honors
Cozarelli Prize. Outstanding paper of year, Physical Sciences group, Proceedings of the National Academy of Sciences; award by the U.S. National Academy of Sciences
Chancellors Award for Contribution to Campus Diversity
Visiting Professor, School of Environmental Science and Engineering, Sun Yat-Sen University, China
Selected one of 100 distinguished alumni in 100 years. Florida State University
Goldschmidt Medal The Geochemical Society
Elected, Fellow, European Association for Geochemistry
Elected Fellow: Geochemical Society
Asteroid (7004) Markthiemens named in his honor, International Astronomical Union
Elected, National Academy of Sciences
Elected, Fellow American Geophysical Union
Elected, American Academy Arts and Sciences
American Chemical Society Distinguished Scientist of the year (San Diego)
Chancellors Associates Award for Excellence in Research
1999 -
Dean of Physical Sciences
E.O. Lawrence Award, U.S. Department of Energy
Chancellors Associates Chair
BiCentennial Volume of Who's Who in Science and Engineering
Alexander von Humboldt Fellowship
Camille and Henry Dreyfus Teacher-Scholar
Postdoctoral Fellow, Enrico Fermi Institute, University of Chicago
Research Interests
In our laboratory, we have developed the analytical capability to measure stable isotope variations at ultra-high precision (0.04 parts per thousand) in sulfur (34S/32S, 33S/32S), oxygen (18O/16O, 17O/16O), carbon (13C/12C), and nitrogen (15N/14N). Using this high precision as a diagnostic tracer, we have developed experimental programs in widely varying research fields which include atmospheric chemistry, the physical chemistry of photochemical reactions, early solar system history, paleo atmospheres, and the origin of life and of the solar system.

Our group employs stable isotope measurements to delineate the fates of different atmospheric species. From combined laboratory photochemistry experiments and field (tropo- and stratospheric) measurements, we are able to determine specific reaction pathways. High altitude samples are taken from aircraft, balloons and rockets to as high as 60 km. Our research sampling focuses upon studying the global impact by many important atmospheric molecules. These species include carbon dioxide, nitrous oxide, carbon monoxide, ozone, and sulfate (acid rain). These samples are collected throughout the world and include our work at the South Pole and in tropical rainforests. Hemispheric aerosol transport is also studied.

Primary Research Area
Physical/Analytical Chemistry
Interdisciplinary interests
Atmospheric and Environmental

Outreach Activities
My contributions to diversity started in 1964 as a teaching volunteer in highly disadvantaged areas and is largely continual by various ways, to the present.

As a reflection of my contributions to diversity within and exterior to UCSD I have been the recipient of the UCSD award for Contributions to Equal Opportunity, Affirmative Action and Diversity. The basis of the nomination was contributions made as a faculty member. This includes broad mentorship beyond the norm of underrepresented students, including high school students. It was also in recognition of the yearly work of bringing in hundreds of students from high school and junior high schools to expose them, for the first time, to the University and stimulate their interest in attending this (or any) university. It also recognized the many lectures to students in areas of high diversity at high school and elementary schools, and from public lectures of many venues.

My own research group is and always has been, highly diverse with underrepresented minorities as well as women.

Each year I have helped host and lecture a meeting with visiting journalists from Latin America and South America as a potential mechanism to amplify academic connections with those countries and provide possible research activities for our students present at UCSD from those countries. I have also participated in lectures and personnel meetings in visiting programs from Mexico and Latin America to raise the visibility of UCSD to those communities across San Diego.

I have arranged and personally guided groups of high school students from under-represented schools in San Diego to my own laboratory in an effort to simultaneously welcome them and encourage them to attend school here. As part of my participation in the Annual Kyoto lecture, I have been involved with facilitating the attendance of more than three hundred high school students to UCSD; predominantly from under-represented groups,many of whom were visiting a university campus for the first time.
Selected Publications