Entitled "Vertical velocities and fine-scale dynamics", and carried out over the last three years within the OPLC team at the MIO, under the direction of Stéphanie Barrillon and Anne Petrenko.
The jury is composed as follows:
- Ms Rosemary MORROW (Professor), LEGOS
- Bruno BLANKE (Research Director), LOPS
- Francesco D'OVIDIO (Research Director), LOCEAN - IPSL
- Mr Frédéric CYR (Research Scientist), Northwest Atlantic Fisheries Centre - Fisheries and Oceans Canada (DFO)
- Mr Xavier CAPET (Research Director), LOCEAN - IPSL
- Ms Anne MOLCARD (Professor), MIO
After the defence, a drinks reception will be held from 1 - 1.30pm in the conviviality room on the first floor of the Océanomed building.
Summary:
The fine oceanic scales (from 0.1 to 100 km, with a lifetime of a few days to a few weeks), characterised by structures such as eddies, fronts or filaments, generate vertical velocities and play a key role in the global balance of the oceans by impacting vertical exchanges that are strongly correlated with climate change (nutritive salts, carbon, marine micro-organisms). These structures are naturally present in the ocean but their rapid evolution makes in situ sampling particularly difficult. Vertical velocities, which are one to two orders of magnitude smaller than horizontal velocities, have long been simply parameterised or neglected because they are considered unmeasurable. The aims of this thesis are to meet this challenge by developing innovative, high-performance techniques for the in situ measurement of vertical velocities, and to understand their influence on fine scales.
The first focus of this thesis is the development of two new methodologies for the in situ measurement of vertical velocities with an accuracy adapted to the target order of magnitude (a few 10-3 m s-1). This has resulted in the ADCP free fall and the Vertical Velocity Profiler, based on tests in semi-controlled environments and at sea, as well as three oceanographic campaigns: FUMSECK (2019), PROTEVS-Gascogne (2022), and BIOSWOT-Med (2023).
The second area of research involves the development of methodologies commonly used in the study of vertical ocean velocities, through the analysis of ADCP data and a numerical ocean circulation model (SYMPHONIE), as well as the resolution of the-ω equation. These approaches were applied as part of the FUMSECK project, making it possible to analyse the influence of vertical movements on phytoplankton dynamics.
Key words: vertical velocities, fine scale, in situ, instrumental development
Thesis defence COMBY Caroline - 27 November 2023 - 09H00
Time: 27 Nov 2023 08:30 AM Paris
Join Zoom Réunion
https://univ-amu-fr.zoom.us/j/84739427980?pwd=SlpwRDlDUStBZzZ5YVA1SUNSQ2…
Meeting ID: 847 3942 7980
Secret code: 186351