PAOC Colloquium - Joern Callies (Caltech)
Using earthquakes to measure ocean warming
More than 90% of the energy trapped on Earth by increasingly abundant greenhouse gases is absorbed by the ocean. Despite much progress over the past 20 years, monitoring the resulting ocean warming remains a challenging sampling problem. In this talk, I will pres-ent a new method that complements existing point measurements by inferring basin-scale deep-ocean temperature change from the travel times of sound waves that are generated by repeating earthquakes. I will show results from two sections in the East Indian Ocean that are 2900 and 4400 km long. The measure-ments capture deep-ocean temperature variations on time scales from a few days to a decade. The approxi-mate vertical structure of these variations can be inferred using measurements at different frequencies. I will argue that the new method, if extended globally, offers useful new constraints on the deep-ocean uptake and transport of heat.
About this Series
The PAOC Colloquium [PAOCC] is a weekly interdisciplinary seminar series that brings together the whole PAOC community. Seminar topics include all research concerning the physics, chemistry, and biology of the atmospheres, oceans and climate, but also talks about e.g. societal impacts of climatic processes. The seminars take place on Monday from 12-1pm. Besides the seminar, individual meetings with professors, post-docs, and students are arranged. Contact: firstname.lastname@example.org.