The PhD defence and trial lecture will be held in Auditorium 1, The Geology Building. In some cases, it will be possible to attend the trial lecture and dissertation digitally, in that case a link to Zoom will be posted.
Trial lecture
Monday 29 August, 10:15-11.00, Aud 1, The Geology Building
The global ocean energy budget
Conferral summary (in Norwegian)
Havet er fullt av roterende vannmasser, såkalte virvler eller eddier. Virvler er stormer som ligner på været med høytrykk og lavtrykk, slik vi kjenner fra atmosfæren. Stormene har stor påvirkning på havets sirkulasjon og dermed også klimaet. Med numeriske modeller og analytiske beregninger undersøkes det i avhandlingen naturen av slike stormer på de høye breddegrader, og hvordan de påvirkes av havbunnens topografi.
Main research findings
Popular scientific article about Trodahl’s dissertation:
Vortices in the Subarctic Seas and their interactions with bottom topography
Coherent swirling bodies of water; mesoscale (10-100 km) vortices, are an essential part of the general ocean circulation. Mesoscale vortices are abundant everywhere in the World Ocean and are vital in upholding equilibrium balances that govern the global circulation and thus also the climate.
In order to obtain a better understanding of the general circulation in the global ocean, there is a need of more insight into vortex life cycles and impacts, such as their formation, spatial structure, distribution, and interactions with neighboring vortices and with the ambient environment. Gaining more knowledge of the mesoscale vortex field is not only crucial for our present-day understanding of the circulation, but also for future predictions of climate.
Studying the mesoscale vortex field is challenging in the polar regions since vortex length scales significantly decrease with latitude. The small length scales make them both harder to observe and to model. In this thesis, simplified theory and idealized and realistic high-resolution modeling is combined to gain insight the mesoscale vortex field in a climate-sensitive high latitude region, namely the Subarctic Seas. A unique, long-lived high pressure system situated in the Lofoten Basin is specifically examined. How this storm has kept intact for perhaps over 100 years has been puzzling, and this thesis shows a direct link to the process responsible for its regeneration.
Photo and other information:
Press photo: Marta Trodahl, portrett; 450px. Photo: Private
Other photo material: Figur med beskrivelse og kreditering som spesifisert i artikkelen over, størrelse 1045px.