18 October 2023
10:00 –11:00 AM (CST)
In California’s San Joaquin Valley, groundwater extraction is causing many adverse impacts including land subsidence and a loss of storage capacity. The remote sensing method of interferometric synthetic aperture radar (InSAR) allows us to map surface deformation across the valley with high spatial and temporal resolution, but we are only scratching the surface in using these data for groundwater management and science. InSAR data can be directly used to monitor subsidence, and I will show how I used these data in the development of a 1-D compaction model which provided insights into the timescales and depth-of-origin of groundwater-driven land subsidence. I will also explain how surface deformation has a direct relationship to groundwater storage changes and demonstrate a new use of InSAR, in conjunction with shallow hydraulic head data, to monitor groundwater storage change with improved accuracy. In this talk, I will give an accessible summary of the novel ways that InSAR data can be integrated into groundwater management and science.
Matt Lees obtained his undergraduate and masters degrees in earth sciences at the University of Cambridge, UK. He recently defended his PhD thesis, titled “Advancing the Use of InSAR for Groundwater Science and Management in California’s San Joaquin Valley,” which he obtained while working in Rosemary Knight’s hydrogeophysics research group at Stanford. He will shortly begin a postdoctoral position at the University of Manchester, England, focusing on the use of remote sensing for improved monitoring of hydrologic systems in arid basins in the Mediterranean, South Asia, and South America. His research targets the intersection of policy and hydrologic science, using Earth monitoring tools to answer questions of direct relevance for water managers.