The discovery of unusual oxygen isotope compositions in ozone and carbon dioxide by Mauersberger and co-workers and Thiemens and co-workers in the 1980s and 1990s has been followed by the challenges of understanding the chemical physics of the non-standard kinetic isotope effects on a molecular level and how they play out on a global scale, with the promise of providing new isotopic tracers of ozone production and transport in the stratosphere and the rates of uptake of atmospheric carbon dioxide by the biosphere. In this talk, I will highlight laboratory experiments (including crossed molecular beam experiments on O+O2 and O+CO2 and bulk photochemistry experiments on CO2 and O2 mixtures) and new stratospheric isotope measurements on air collected by aircraft and balloon flights that provide new insight into and constraints on the chemical physics of these unusual isotope effects needed to support their growing application to solving problems in the Earth and environmental sciences across a variety of disciplines.










Kristie Boering (University of California Berkeley)