Paul O. Wennberg is the R. Stanton Avery Professor of Atmospheric Chemistry and Environmental Science and Engineering at the California Institute of Technology (Caltech). He is the director of the Ronald and Maxine Linde Center for Global Environmental Science. He is chair of the Total Carbon Column Observing Network and a founding member of the Orbiting Carbon Observatory project, which created NASA's first spacecraft for analysis of carbon dioxide in the atmosphere. He is also the principal investigator for the Mars Atmospheric Trace Molecule Occultation Spectrometer (MATMOS) to investigate trace gases in Mars's atmosphere.