Seismic ocean thermometry

Speaker: 

Wenbo Wu & Jörn Callies

Affiliation: 

Division of Geological and Planetary Sciences, California Institute of Technology

Date: 

Fri, 13/11/2020 - 10:00am to 11:00am

Venue: 

Via Zoom (see link below)

Abstract: 

More than 90% of the energy trapped on Earth by increasingly abundant greenhouse gases is absorbed by the ocean. Monitoring the resulting ocean warming remains a challenging sampling problem.

To complement existing point measurements, we introduce a method that infers basin-scale deep-ocean temperature changes from the travel times of sound waves that are generated by repeating earthquakes. A first implementation of this seismic ocean thermometry constrains temperature anomalies averaged across a 3000-kilometer-long section in the equatorial East Indian Ocean with a standard error of 0.0060 kelvin.

Between 2005 and 2016, we find temperature fluctuations on time scales of 12 months, 6 months, and ~10 days, and we infer a decadal warming trend that substantially exceeds previous estimates.

Hosted by the UNSW Climate Change Research Centre & the School of Mathematics and Statistics.

Join via: https://unsw.zoom.us/s/88057438480

Biography

Dr. Wenbo Wu is a postdoc scholar in seismology working at seismological laboratory at the California Institute of Technology. He received his B.Sc./M.Sc. degrees from the University of Science and Technology of China (USTC). He obtained a PhD degree in geophysics from the department of Geosciences at Princeton University. His research interests are seismic ocean thermometry, numerical methods of seismic wave propagation and deep Earth seismic structure.

Dr. Jörn Callies is Assistant Professor of Environmental Science and Engineering at the California Institute of Technology. He holds a B.Sc./M.Sc. in meteorology from the University of Hamburg, Germany, and a Ph.D. in physical oceanography from the Massachusetts Institute of Technology and Woods Hole Oceanographic Institution Joint Program in Oceanography.

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