The PhD defence will be in Abels utsikt, 12. etasje, Niels Henrik Abels hus. The host of the session will moderate the technicalities while the chair of the defence will moderate the disputation.
Ex auditorio questions: the chair of the defence will invite the audience to ask questions ex auditorio at the end of the defence.
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Join the disputation
The webinar opens for participation just before the disputation starts, participants who join early will be put in a waiting room.-
Submit request to access (available from 15.08 1:15 pm until 01.09 1:15 pm)
Trial lecture
1st of September, time: 10:15 am, Abels utsikt, 12. etasje, Niels Henrik Abels hus.
- Join the trial lecture
The webinar opens for participation just before the trial lecture starts, participants who join early will be put in a waiting room.
Main research findings
The societal importance of weather drives a continuous effort to improve short- and long-term numerical weather prediction. A better knowledge of the conditions in the stratosphere, the atmospheric region from 10 to 50 kilometers altitude, could be key in enhancing long-term weather forecasts on the Earth’s surface. Due to sparseness of stratospheric wind observations, this thesis aims at contributing to the development of remote sensing techniques.
Infrasound is inaudible low-frequency sound generated by, for example, ocean waves. These sound waves undergo little damping and can travel for long distances through atmospheric waveguides that include the stratosphere. Infrasound that has passed through the stratosphere to be recorded at ground level carries information about the wind and temperature of this region. This implies that if the signal characteristics are sufficiently interpreted and described, ground-based measurements of infrasound could function as a form of stratospheric remote sensing.
In this thesis, mathematical modelling and machine learning techniques are developed to relate infrasound recordings to stratospheric weather dynamics. A derived model is verified by estimating stratospheric winds in the Arctic region solely from ground-based infrasound data. The results indicate a potential for using these low-frequency sound waves for near real-time probing of stratospheric winds.
Adjudication committee
- Professor Luitgard Veraart, London School of Economics and Political Science
- Professor Knut Sølna, University of California
- Associate Professor David Ruiz Baños, University of Oslo
Supervisors
- Professor Fred Espen Benth, University of Oslo
- Associate Professor Sven Peter Näsholm, University of Oslo/NORSAR
- Research Scientist Quentin Brissaud, NORSAR
Chair of defence
Head of Department Geir Dahl
Host of the session
Associate Professor David Ruiz Baños, University of Oslo