Pierre-Amaël Auger

Institute of Research for Development | IRD · 197 - Ocean Physics Laboratory (LPO)

A realistic modeling approach is designed to address the role of winter mixing on the interannual variability of plankton dynamics in the north-western (NW) Mediterranean basin. For the first time, a high-resolution coupled hydrodynamic–biogeochemical model (Eco3m-S) covering a 30-year period (1976–2005) is validated on available in situ and satell...

A comparative box analysis based on a multi-decadal physical–biogeochemical hindcast simulation (1980–2009) was conducted to characterize the drivers of the spatial distribution of phytoplankton biomass and production in the north-west (NW) African upwelling system. Alongshore geostrophic flow related to large-scale circulation patterns associated...

Small pelagic fish (SPF) species are heavily exploited in eastern boundary upwelling systems (EBUS) as their transformation products are increasingly used in the world’s food chain. Management relies on regular monitoring, but there is a lack of robust theories for the emergence of the populations’ traits and their evolution in highly variable envi...

The vertical variability in the oxygen minimum zone (OMZ) in the eastern South Pacific (ESP; 0–40°S) is characterized by the influence of anticyclonic intrathermocline eddies (ITEs), which are subsurface‐intensified mesoscale features that are frequently generated in the coastal upwelling zone off Peru and Chile. The unique lens‐shaped signatures t...

Studies assessing potential measures to counteract the marine deoxygenation attributed to anthropogenic activities have been conducted in a few coastal environments and at regional scale, but not yet on a global scale. One way toward global scale artificial oxygenation would be to use oxygen produced as a by-product from hydrogen-production through...

Marine temperature extremes are anomalous ocean temperature events, often persisting over several weeks or longer, with potential impacts on physical and ecological processes that often encompass socio-economic implications. In recent years, a considerable effort has been directed at the development of metrics allowing an objective characterization...

Eastern boundary upwelling systems feature strong zonal gradients of physical and biological properties between cool, productive coastal oceans and warm, oligotrophic subtropical gyres. Zonal currents and jets (striations) are therefore likely to contribute to the transport of water properties between coastal and open oceanic regions. For the first...

The following are available online at https://www.mdpi.com/article/10.3390/fluids6120455/s1, Figure S1: Striation expressions in hydrographical tracers in the two study regions from alternate data; Figure S2: Anisotropic ratio for hydrographical tracers in the two study regions from alternate data; Figure S3: Cross-striation profiles of spatially h...

Eastern boundary upwelling systems feature strong zonal gradients of physical and biological ocean properties between cool, productive coastal oceans and warm, oligotrophic subtropical gyres. Zonal currents and jets (striations) are therefore likely to contribute to the transport of water properties between coastal and open oceanic regions. Multi-s...

The El Niño Southern Oscillation (ENSO) produces global marine environment conditions that can cause changes in abundance and distribution of distant fish populations worldwide. Understanding mechanisms acting locally on fish population dynamics is crucial to develop forecast skill useful for fisheries management. The present work addresses the rol...

Patagonia, Enero 2020

Iron is known to be the limiting nutrient for the phytoplankton growth over ~40% of the global ocean and to impact the structure of marine ecosystems. Dissolved iron (DFe) is assumed to be the only form available to phytoplankton while particulate iron (PFe) has mostly been considered for its role in the biogenic iron remineralization and induced s...

In 2016, a massive harmful algal bloom (HAB) of Alexandrium catenella around Chiloé island caused one of the major socio-ecological crisis in Chilean history. This red tide occurred in two distinct pulses, the second, most anomalous, bursting with extreme toxicity on the Pacific coast, weeks after the highly controversial dumping off Chiloé of 4,70...

Plain language summary Oxygen is a key requirement for respiration by marine living organisms. Warming of the atmosphere and the ocean surface reduces the oxygenation of offshore waters. Similarly, the extra load of nutrients from agriculture or waste waters modifies algal production, particularly in coastal regions, often resulting in oxygen‐deple...

La investigación busca evaluar el impacto de caminos preferidos de remolinos de mesoescala (distinguiendo entre estacionarios y transientes) sobre varios trazadores físicos (temperatura, salinidad), biogeoquímicos (oxígeno, carbón, nutrientes) y otros trazadores en el Pacífico Oriental frente a las costas de California y Chile. Mientras estudios pr...

Marine debris are a growing global concern, with huge amounts of plastic accumulating inside the five subtropical gyres in the North Atlantic, South Atlantic, North Pacific, South Pacific, and Indian Oceans. Plastic items of various sizes are swallowed by marine life and have been reported to penetrate the food chain all the way up to human bodies,...

This is a scientific report solicited by the Dirección General del Territorio Marítimo y de Marina Mercante (DIRECTEMAR) of the Chilean Navy in June 2017. A foreign (Canadian) company had been making numerous appearances in the Chilean and International Press, and conducting an advertising campaign, to promote the commercial fertilization of Chilea...

Understanding the influence of mesoscale and submesoscale features on the structure of phytoplankton is a key aspect in the assessment of their influence on marine biogeochemical cycling and cross-shore exchanges of plankton in Eastern Boundary Current Systems (EBCS). In this study, the spatio-temporal evolution of phytoplankton size classes (PSC)...

Mesoscale eddies play a fundamental role in the transport of heat, nutrients and biota in the ocean. It has been suggested that their westward propagation may take place preferentially through specific pathways, which tend to be alternately dominated by (anti)cyclonic eddies and coincide with striations of the zonal current. While various studies h...

In recent years, quasi-zonal mesoscale jet-like features or striations have been ubiquitously detected in the time-mean circulation of the world ocean using satellite altimetry and in situ data. Most likely the result of some organization of the mesoscale eddy field such as preferred eddy tracks, these striations may be able to advect and mix physi...

Striations and mesoscale activity in the Pacific upwelling systems: steady state and transient perspectives.

Los remolinos de mesoescala juegan un papel fundamental en el transporte de calor, nutrientes y biota en los océanos. Se ha sugerido que su propagación hacia el oeste se haría preferentemente por rutas específicas, las que tienden a ser alternamente dominadas por remolinos (anti)ciclónicos y coinciden con las estriaciones de la corriente zonal [Bel...

The objective of this study was to assess the effect of environmental variations on the abundance of Sardinella aurita and Sardinella maderensis in Senegalese waters in the upwelling system. Monthly data indicating the abundance of sardinella were first estimated from commercial statistics, using Generalized Linear Model from 1966 to 2011. Abundanc...

Deep convection occurs in oceanic regions submitted to strong atmospheric buoyancy losses and results in the formation of deep water masses (DWF) of the ocean circulation. It shows a strong interannual variability, and could drastically weaken under the influence of climate change. In this study, a method is proposed to monitor quantitatively deep...

A 3D hydrodynamic-biogeochemical coupled model has been used to estimate a budget of organic carbon and its interannual variability over the 5-year period 2004-2008 in the North-Western Mediterranean Open Sea (NWMOS). The comparison of its results with in situ and satellite observations reveals that the timing and the magnitude of the convection an...

A comparative box analysis based on a multi-decadal physical-biogeochemical hindcast simulation (1980–2009) was conducted to characterize the drivers of the spatial distribution of phytoplankton biomass and production in the North-West (NW) African upwelling system. Alongshore geostrophic flow related to large scale circulation patterns associated...

In this study, we report the distributions of total dissolvable cadmium and particulate cadmium from 27 stations in southern Moroccan coastal waters (22°N–30°N), which is part of the North-West African upwelling system. These distributions were predominantly controlled by upwelling of the North Atlantic Central Waters (NACWs) and uptake by primary...

Using state-of-the art dynamical and biogeochemical models, we aimed at documenting the regionalization and seasonal variability of the ocean biogeochemistry in the North West African upwelling system. An interannual simulation covering the 1980-2009 period have been performed and has been shown to represent reasonably well the dynamical, biogeoche...

In Brehmer Patrice (ed.), Ba B. (ed.), Kraus G. (ed.), Gomez M.M. (collab.), Diogoul N. (collab.), Brandt P. (collab.), Sow B.A. (collab.), Lazar A. (collab.), Capet X. (collab.), Fock H. (collab.), Machu Eric (collab.), Diadihou H.D. (collab.), Jouffre Didier (collab.), Diallo I. (collab.), Schmidt J. (collab.), Ekau W. (collab.), Gaye A. (collab....

The International Commission for the Conservation of Atlantic Tunas ‘ICCAT’, Standing Comitee on Research and Statistics, SCRS/2014/077.

Sardinella aurita, or round sardinella, has been the main small pelagic fish species harvested off Senegal and Mauritania coasts over the last 4 decades and plays a central role for sub-regional food security and economic incomes. The landings of this species have strongly declined recently. Intense exploitation and climate change are acting togeth...

Low-salinity water (LSW, Salinity < 37.5) lenses detached from the Rhone River plume under specific wind conditions tend to favour the biological productivity and potentially a transfer of energy to higher trophic levels on the Gulf of Lions (GoL). A field cruise conducted in May 2006 (BIOPRHOFI) followed some LSW lenses by using a lagrangian strat...

A coupled hydrodynamic-biogeochemical modelling is developed to address main mechanisms that drive the particulate organic carbon (POC) deposition in the Gulf of Lions (NW-Mediterranean). Low-salinity water (LSW, salinity <37.5) lenses detached from the Rhone River plume under specific wind conditions tend to favour the biological productivity and...

The pelagic planktonic ecosystem dynamics of the north-western Mediterranean Sea has been studied by a realistic modelling approach. The dynamics of coastal ecosystems sustained by the Rhone River nutrient loads, and offshore ecosystems are considered separately. Through an high resolution modelling of the Rhone River plume, a specific calibration...