John P. O’Brien is a program officer for the Science program at the Heising-Simons Foundation. Prior to joining the Foundation in 2024, John performed research on extreme weather amplified by anthropogenic climate change as a research affiliate with Lawrence Berkeley National Laboratory in Berkeley, California. In addition, he was also a research affiliate at Cal Poly Humboldt in Arcata, California, where he studied how climate change may be impacting the growth and distribution of California’s iconic redwood trees. Previously, John was a postdoctoral research fellow at the National Center for Atmospheric Research in Boulder, Colorado, where he used global climate model output to study how climate change affects large-scale circulation variability and tropical-extratropical teleconnections such as ENSO (El Niño Southern Oscillation). In addition, he also spent time working in private industry as an exploration geophysicist using seismic data to map subsurface formations, fluids, and faults. John earned his Ph.D. in climate and atmospheric science from the University of California, Santa Cruz, a graduate certificate in spatial statistics from the University of Alberta, Edmonton, and a bachelor’s degree in engineering physics from the Colorado School of Mines.