Geoscientific Colloquium with Prof. Roland Bürgmann (UC Berkeley)

Learning from Climate- and Weather-Driven Solid-Earth Deformation and Seismicity

There is evidence for the effects of climatic processes and weather on deformation and seismicity in the lithosphere over a wide range of time scales, ranging from load cycles associated with the ice ages to the effects of short-term weather events. Space- and ground-based geophysical observations allow us to capture the redistribution of surface loads in the form of water, ice, and sediments, as well as near-surface pressure and temperature changes in the atmosphere and varying fluid pressure in the shallow subsurface. While earthquakes are generally the result of tectonic activity, the climatic forcings induce stress changes on faults that in some cases can be shown to significantly encourage or retard the occurrence of earthquakes. Climate-earthquake interactions are mostly subtle and proving the interaction between climate and earthquakes requires careful mechanical modeling and statistical analysis. While investigations of these interactions are not likely to be relevant for the characterization and mitigation of earthquake hazard, they provide important insights into the physical processes associated with lithospheric deformation, the earthquake cycle and frictional faulting in the Earth. I will provide an overview on the topic and introduce several case studies to illuminate the opportunities and challenges involved with investigations of climate-driven solid-earth deformation.