'The marine biogeochemical cycles: Processes and role in the global carbon cycle' by Dr. Olivier Aumont


Dr. Olivier Aumont's short biography:

Dr. Olivier Aumont is a research scientist from IRD (Institut de Recherche pour le Développement) working at LOCEAN in Paris. His research interests are in the field of global carbon cycle, marine biogeochemical cycles and marine ecosystems
More specifically, he is interested in the role that specific physical, biological and chemical processes play in the marine biogeochemical cycles as well as in the transfer of energy along the oceanic trophic food webs. He is the creator and the main developer of the PISCES biogeochemical model that is embedded in several Earth System Models which participate to CMIP (Coupled Model Intercomparison Project) and in different research and operational modeling platforms of the ocean. 
Native of France, Dr. Olivier Aumont completed a PhD in oceanography at the University Pierre and Marie Curie in Paris (1998). He has conducted research at the Max Planck Institute for Meteorology in Hamburg (Germany).

Lecture's abstract - 'The marine biogeochemical cycles: Processes and role in the global carbon cycle':

The ocean is a major component of the global carbon cycle, being the second largest reservoir of carbon after rocks. Furthermore, about a third of the anthropogenic emissions of CO2 to the atmosphere accumulates in the ocean. The oceans are also a resource for food, being a major source of animal proteins in many coastal regions, and represent about 60% of the total economic value of the biosphere. 
In a first part, Dr. Aumont will present the major characteristics of the ocean carbon cycle as well as of the cycles of the main related elements (N, P, Si, Fe and O2). Biological processes play a critical role in these cycles. In the upper part of the ocean, photosynthetic phytoplankton fixes CO2 and nutrients and produces O2 and organic matter. A small part of this organic matter escapes local remineralization and is transported to the interior of the ocean as both particles and dissolved organic compounds. After a short presentation of the main characteristics of the marine biological activity, he will review the major processes that control the magnitude of this biological pump of carbon. 
In a second part, he will discuss the potential consequences future climate change might have on the marine carbon cycle. Projections using Earth System Models suggest some consistent changes, in particular a decrease of the efficiency in the export of carbon out of the upper ocean. However, large uncertainties remain, especially at the regional scale which he will illustrate based on some examples.

Recommended background publication on this presentation:

Bopp, L., Resplandy, L., Orr, J. C., Doney, S. C., Dunne, J. P., Gehlen, M., Halloran, P., Heinze, C., Ilyina, T., Séférian, R., Tjiputra, J., and Vichi, M. : Multiple stressors of ocean ecosystems in the 21st century:projections with CMIP5 models. Biogeosciences, 10, 6225–6245, (2013). Doi:10.5194/bg-10-6225-2013.