Dr. Brad Weir is a research scientist at NASA Goddard Space Flight Center and Universities Space Research Association. He is the lead developer of NASA's Goddard Earth Observing System (GEOS) Constituent Data Assimilation System (CoDAS) — a state-of-the-art statistical method for estimating atmospheric trace gas abundances based on satellite observations. His research focuses on developing and applying mathematical and statistical methods to address questions about the physics, chemistry, and biology of the Earth's atmosphere, ocean, and land surface. His work has appeared in Science, the New York Times, the websites of National Geographic and the BBC, the NASA COVID-19 Dashboard, and the NASA/ESA/JAXA trilateral Earth Observing Dashboard.