Ralph Keeling is professor of geochemistry in the Geosciences Research Division of Scripps Institution of Oceanography, University of California, San Diego.

His research focuses on atmospheric composition, the carbon cycle, and climate change. He is considered a leading investigator of the global oxygen cycle for his precise measurements and analysis techniques.  Keeling developed his method for measuring atmospheric oxygen levels utilizing interferometry techniques in the laboratory. He began pioneering measurements of changes in atmospheric oxygen levels from air samples collected at stations around the world. The measurements continue at nine sampling stations, extending from Ellesmere Island in northern Canada over the equator to two Antarctic stations.

Measurements from his group show that the atmosphere O2 is decreasing at a small but measurable rate due primarily to the burning of fossil fuels.    From 1991 to 2011, the atmosphere lost on average 19 out of every million O2 molecules in the atmosphere.  Establishing this rate was a milestone for improving our understanding of the processes controlling the buildup of CO2 in the atmosphere.

Keeling’s research also involves measuring changes in the Ar/N2 ratio of the atmosphere, with the goal of resolving changes caused by warming and cooling of the oceans and associated changes in the solubility of Ar and N2 in seawater.  These measurements have the potential to quantify changes in global ocean heat storage.  His research further includes developing methods to quantify greenhouse gas emissions using atmospheric measurements.

Born in La Jolla, Calif., Keeling received a B.S. in physics, summa cum laude, from Yale University, and a PhD in applied physics from Harvard University.

He previously served as a visiting scientist at the National Center for Atmospheric Research (NCAR). He completed postdoctoral fellowships at NCAR and Harvard.

He received the Rosenstiel Award from the University of Miami’s Rosenstiel School of Marine and Atmospheric Science, the Outstanding Publication Award from NCAR, and was an H. Burr Steinbach Scholar at Woods Hole Oceanographic Institution. He also was a Climate Center Visitor at Columbia University’s Lamont-Doherty Earth Observatory.

Keeling is a member of the American Geophysical Union.

He is the author of more than 65 scientific research papers.