Trial Lecture and Thesis Defense - Master of Science Luc Ludovic Nicolas Hallali

Master of Science Luc Ludovic Nicolas Hallali  will hold the Trial Lecture and Thesis Defense for the PhD degree in Science on Monday, September 14, 2026.

Trial Lecture

The Trial Lecture will take place 10:15 - 11:15.

The title of the Trial Lecture is:

« Concepts, comparisons and applications of short- and long-memory time series »

Thesis Defense

The Thesis Defense will take place 12:15 - 15:00.

The title of the thesis is:

« Bayesian analysis of Arctic stability loss »

Abstract

The North Atlantic-Arctic system, comprising the AMOC, Greenland Ice Sheet, and Arctic sea ice, is undergoing major change. Whether this reflects reversible forcing or true stability loss remains unclear, and standard methods can be biased. This thesis develops a Bayesian framework to detect stability changes in geophysical time series and applies it to these systems. Results show robust early warning signals of AMOC destabilization, evidence that instability may spread across North Greenland, and contrasting behavior in Arctic sea ice, with the Barents Sea showing early warning signals while basin-wide ice remains stable. Overall, the findings provide a probabilistic assessment of Arctic stability under global warming.

Supervisory Committee

• Postdoc Eirik Myrvoll-Nilsen, Department of Mathematics and Statistics, UiT (Main Supervisor)
• Professor Sigrunn H. Sørbye, Department of Mathematics and Statistics, UiT

Evaluation Committee

• 1st Opponent: Assistant Professor Johannes Jakob Lohmann, Niels Bohr Institute, University of Copenhagen, Denmark
• 2nd Opponent: Senior Lecturer Daniela Castro-Camilo, School of Mathematics & Statistics, University of Glasgow,  Scotland, UK 
• Internal member and leader of the committee: Professor Patrick Guio, Department of Physics and Technology, UiT, Norway 

Streaming

The Trial Lecture and Thesis Defense will be streamed via Panopto:

Trial Lecture (10:15 - 11:15)
Watch the Trial Lecture

Thesis Defense (12:15 - 15:00)
Watch the Thesis Defense

Thesis

The thesis is available in Munin:

View the thesis in Munin