John Dykema, Ph.D.

John Dykema, project scientist in the School of Engineering and Applied Sciences, Harvard University, is an applied physicist focused on research at the intersection of atmospheric chemistry and atmospheric radiation. He brings a background in semiconductor technology to the development of innovative observing systems for radiometry, aerosol measurements and atmospheric profiling. Dykema is a member of the DCOTSS mission, working to extract observational constraints to update the radiative properties of upper troposphere–lower stratosphere aerosols. This investigation revisits the climate impact of stratospheric aerosol, taking account of new discoveries regarding the aerosol’s complex morphology and composition. He has led the design of laser-based calibration technology to link satellite measurements of climate quantities to fundamental physics. To enhance the scientific value of novel instrumentation, he has studied new approaches to data analysis. These methods include linear stochastic modeling, optimal detection/fingerprinting and adaptive signal processing. He has applied these methods to remotely sensed observations and climate model output to infer climate sensitivity, quantify radiative processes and estimate climate impacts. His advisory and advocacy activities include membership in NASA and international measurement teams dedicated to advancing physically rigorous calibration of climate measurements.