RSI Research Seminar

RSI Special Lunchtime Seminar, May 24th 12 noon - Zhongwen Zhan

In early 2020, RSI moved forward with funding our first large-scale research grant, to fund a study into the viability of using fiber-based seismic sensing of groundwater and soil moisture, led by Professor Zhongwen Zhan.

Fiber seismic sensing of vadose zone soil moisture

Vadose zone soil moisture dynamics in semi-arid regions are critical to ecosystems and water management, but their direct observation at large spatiotemporal scale remains challenging. Utilizing pre-existing fiber-optic cables as seismic sensors, we demonstrate a fiber seismic sensing principle to robustly capture the vadose zone soil moisture dynamics. Our observations in Ridgecrest, California, confirm a long-held speculation that the amount of precipitation is not a reliable predictor of vadose zone water availability in semi-arid climates. With hydrological modeling, we elucidate the highly nonlinear relationship between precipitation and shallow subsurface water storage, and the impact of long-term drought on vadose zone water availability. The findings highlight the potential of fiber seismic sensing for vadose zone hydrology in face of climate change, especially as droughts escalate.

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Join us every other Monday at noon for lunch and a 30-minute research talk, presented by Resnick Sustainability Institute Graduate Fellows and Caltech researchers funded by the Resnick Sustainability Institute. To see the full schedule of speakers, visit the RSI Research Seminar web page. Seminars currently take place in a hybrid format, both in-person (Jorgensen building first-floor conference room) and via Zoom. For more information and to get the Zoom login info, please reach out to [email protected]