Earth System Science Seminar Series: Dr. Qiang Fu

EARTH SYSTEM SCIENCE
SEMINAR SERIES

October 22, 2026
12:00 - 1:00 PM
Y2E2, Room 299 

 Qiang Fu, Ph.D.
Professor
Department of Atmospheric and Climate Science
University of Washington

 

“Global Stratospheric Methane Loss from Satellite Observations”

 

Abstract
Methane (CH4) is the second most important anthropogenic greenhouse gas after carbon dioxide, yet its variability and long-term increase remain poorly understood, in part because of large uncertainties in atmospheric removal processes. Stratospheric CH4 oxidation represents an important sink in the global methane budget and a major source of stratospheric water vapor, while methane–chlorine reactions further modulate catalytic ozone chemistry. Until now, estimates of stratospheric CH4 chemical loss have relied exclusively on chemistry–climate models (CCMs), resulting in substantial uncertainty. Here, I present an observationally based estimate of stratospheric methane loss (LSTR), derived from the CH4 diabatic flux across an isentropic surface fitted to the tropical tropopause using satellite observations of CH4 concentrations, temperature, and radiative heating rates. It is shown that both reanalysis and CCMs systematically underestimate stratospheric methane loss. Incorporating our observational estimate of LSTR into the bottom-up global methane budget reduces the reported imbalance for the 2000s, bringing it into close agreement with the imbalance inferred from top-down estimates. These results demonstrate the critical role of observational constraints on stratospheric methane loss in reconciling the global CH4 budget and carry important implications for understanding stratospheric water vapor and ozone chemistry.

 

Biography
Qiang Fu is a professor in the Department of Atmospheric and Climate Science at the University of Washington (UW) in Seattle.  He received his bachelor’s and master’s degrees from Peking University and earned his Ph.D. from the University of Utah. He was on the faculty at Canada’s Dalhousie University before joining the UW in 2000, where he has been a full professor since 2006.  Fu’s main research interests include atmospheric radiation and cloud processes, atmospheric remote sensing, cloud/aerosol/radiation/climate interactions, stratospheric circulation and stratosphere-troposphere exchanges/coupling, and climate and climate change. He is a member of the National Academy of Sciences (NAS) and the Washington State Academy of Sciences (WSAS), and a Fellow of the American Meteorological Society (AMS), the American Geophysical Union (AGU), and the American Association for the Advancement of Science (AAAS). His many honors include the Alexander von Humboldt Research Award and the AMS Jule G. Charney Medal, recognizing his distinguished and continuing achievements in original research. 

https://atmos.washington.edu/~qfu