Séminaire
Impact of finescale currents on biogeochemical cycles in a changing ocean
Marina Lévy
Finescale currents, O(1-100 km, days-months), are actively involved in the transport and transformation of biogeochemical tracers in the ocean. In this seminar, I will discuss current knowledge of their overall impact on large-scale biogeochemical cycling on the time scale of years, which remain poorly understood due to the multi-scale nature of the problem.
Description
Finescale currents, O(1-100 km, days-months), are actively involved in the transport and transformation of biogeochemical tracers in the ocean. In this seminar, I will discuss current knowledge of their overall impact on large-scale biogeochemical cycling on the time scale
of years, which remain poorly understood due to the multi-scale nature of the problem. I will present the history of the study of these impacts, which have started roughly 30 years ago, when I arrived at LODYC (now LOCEAN). I will examine how eddy-fluxes and upscale
connections enter the large-scale balance of biogeochemical tracers. I will show that the overall contribution of eddy-fluxes to primary production and carbon export may not be as large as for oxygen ventilation. I will highlight the importance of finescales to low-frequency natural variability through upscale connections. I will show that finescales may buffer the negative effects of climate change on the functioning of biogeochemical cycles.
These different points will be illustrated using recent (mostly>2018) work conducted at LOCEAN-IPSL.
I will call for significant interdisciplinary efforts to properly
account for the cross-scale effects of finescales on biogeochemical
cycles in climate projections.
Informations supplémentaires
Lien zoom: https://cnrs.zoom.us/j/94865385312?pwd=bTNlZ2hhaDZLNDkzWFZMTzR6TUNVQT09