The Impact of Submesoscale Physics on Primary Productivity of Plankton

Mahadevan, Amala

doi:10.1146/annurev-marine-010814-015912

Cited by 476 publications

(530 citation statements)

References 108 publications

Supporting

Mentioning

446

Contrasting

Unclassified

Order By: Relevance

“…The nutrient enrichment from the rivers around the basin alone appears to be too low to maintain such a persistent basinwide feature except the Northwestern shelf. The recent modeling study by Oguz (submitted) relates this feature to the frontogenesis mechanism of the Rim Current circulation arising from its nonlinearity and collapse of the along-front geostrophic balance (Mahadevan, 2016). The resulting ageostrophic cross-frontal vertical circulation cell then provides high vertical velocities (∼10-50 m d −1 ) at meander crests on the less dense coastal anticyclonic sides of the front.…”

Section: Stressor 4: Invasion By Alien Gelatinous Speciesmentioning

confidence: 94%

Controls of Multiple Stressors on the Black Sea Fishery

Oğuz

2017

Front. Mar. Sci.

View full text Add to dashboard Cite

Black Sea is one of the most severely degraded and exploited large marine ecosystems in the world. For the last 50 years after the depletion of large predatory fish stocks, anchovy (with the partial contribution of sprat) has been acting as the main top predator species and experienced a major stock collapse at the end of 1990s. After the collapse, eastern part of the southern Black Sea became the only region sustaining relatively high anchovy catch (400,000 tons) whereas the total catch within the rest of the sea was reduced to nearly its one-third. The lack of recovery of different fish stocks under a slow ecosystem rehabilitation may be attributed, on the one hand, to inappropriate management measures and the lack of harmonized fishery policy among the riparian countries. On the other hand, impacts of multiple stressors (eutrophication, alien species invasions, natural climatic variations) on the food web may contribute to resilience of the system toward its recovery. The overfishing/recovery problem therefore cannot be isolated from rehabilitation efforts devoted to the long-term chronic degradation of the food web structure, and alternative fishery-related management measures must be adopted as a part of a comprehensive ecosystem-based management strategy. The present study provides a data-driven ecosystem assessment, underlines the key environmental issues and threats, and points to the critical importance of holistic approach to resolve the fishery-ecosystem interactions. It also stresses the transboundary nature of the problem.

show abstract

Section: Stressor 4: Invasion By Alien Gelatinous Speciesmentioning

confidence: 94%

Controls of Multiple Stressors on the Black Sea Fishery

Oğuz

2017

Front. Mar. Sci.

View full text Add to dashboard Cite

show abstract

“…The dynamics associated with these features result in enhanced vertical velocities that may locally generate mixing or enforce stratification on time scales that range from a few days to several months and from a few km to 100 km (Mahadevan, 2016;McWilliams, 2016). Vertical motions drive the exchange of properties between the surface and the ocean interior (Klein and Lapeyre, 2009) by, for instance, bringing nutrients to the surface ocean, and thereby fuelling phytoplankton production and growth and/or permitting the downward export of organic matter, and thus increasing the export of carbon.…”

Section: Introductionmentioning

confidence: 99%

A Multiplatform Experiment to Unravel Meso- and Submesoscale Processes in an Intense Front (AlborEx)

et al. 2017

Self Cite

View full text Add to dashboard Cite

The challenges associated with meso-and submesoscale variability (between 1 and 100 km) require high-resolution observations and integrated approaches. Here we describe a major oceanographic experiment designed to capture the intense but transient vertical motions in an area characterized by strong fronts. Finescale processes were studied in the eastern Alboran Sea (Western Mediterranean) about 400 km east of the Strait of Gibraltar, a relatively sparsely sampled area. In-situ systems were coordinated with satellite data and numerical simulations to provide a full description of the physical and biogeochemical variability. Hydrographic data confirmed the presence of an intense salinity front formed by the confluence of Atlantic Waters, entering from Gibraltar, with the local Mediterranean waters. The drifters coherently followed the northeastern limb of an anticyclonic gyre. Near real time data from acoustic current meter data profiler showed consistent patterns with currents of up to 1 m/s in the southern part of the sampled domain. High-resolution glider data revealed submesoscale structures with tongues of chlorophyll-a and oxygen associated with the frontal zone. Numerical results show large vertical excursions of tracers that could explain the subducted tongues and filaments captured by ocean gliders. A unique aspect of AlborEx is the combination of high-resolution synoptic measurements of vessel-based measurements, autonomous sampling, remote sensing and modeling, enabling the evaluation of the underlying mechanisms responsible for the observed distributions and biogeochemical patchiness. The main findings point to the importance of fine-scale processes enhancing the vertical exchanges between the upper ocean and the ocean interior.

show abstract

“…Martin, 2013;McGuilicuddy, 2016). This can have a significant impact on primary productivity (Oschlies and Garçon, 1998;Mahadevan, 2016) and thus on the biological C pump (Levy et al, 2013) and associated export (Siegel et al, 2016). Mesoscale eddies modify the vertical structure of the water column: cyclones and anticyclones respectively shoal and deepen isopycnals (McGuillicuddy et al, 1998).…”

Section: Introductionmentioning

confidence: 99%

“…Eddy stirring and trapping further influence biogeochemical and ecological processes (McGuillicuddy, 2016 for a review). Submesoscale dynamics enhance the supply of nutrients in the euphotic zone in nutrient depleted areas and also influence the light exposure of phytoplankton by modifying density gradient in the surface layer, which contribute significantly to phytoplankton production (Mahadevan, 2016) and 10 community structure variability (Cotti-Rausch et al, 2016). The underlying biogeochemical submesoscale processes are particularly challenging to describe and understand because of their ephemeral nature.…”

Section: Introductionmentioning

confidence: 99%

“…For the moment, submesoscale dynamics have been predominately investigated through the analysis of numerical simulation. The lack of in-situ observations at an appropriate spatio-temporal resolution makes difficult the integration of these in-situ data with the model simulations, and it remains still unclear how these processes 15 affect the global state of the ocean (Mahadevan, 2016).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Coupling physics and biogeochemistry thanks to high resolution observations of the phytoplankton community structure in the North-Western Mediterranean Sea

Marrec¹,

Doglioli²,

Grégori³

et al. 2017

Preprint

View full text Add to dashboard Cite

Abstract. Fine-scale physical structures and ocean dynamics strongly influence and regulate biogeochemical and ecological processes. These processes are particularly challenging to describe and understand because of their ephemeral nature. The OSCAHR (Observing Submesoscale Coupling At High Resolution) campaign has been conducted in fall 2015 in which, a fine-scale structure in the North Western Mediterranean Ligurian subbasin 15 was pre-identified using both satellite and numerical modeling data. Along the ship track, various variables were measured at the surface (temperature, salinity, chlorophyll-a and nutrients concentrations) with ADCP current velocity. We also deployed a new model of CytoSense automated flow cytometer (AFCM) optimized for small and dim cells, for near real-time characterization of surface phytoplankton community structure of surface waters with a spatial resolution of few km and a hourly temporal resolution. For the first time with this type of AFCM 20 we were able to resolve Prochlorococcus and Synechococcus picocyanobacteria. The vertical physical dynamics and biogeochemical properties of the studied area were investigated by continuous high resolution CTD profiles thanks to a moving vessel profiler (MVP) during the vessel underway associated to a 1-m vertical resolution pumping system deployed during fixed stations. The observed fine-scale feature presented a cyclonic structure with a relatively cold core surrounded by warmer waters. Surface waters were totally depleted in nitrate and 25 phosphate. In addition to the doming of the isopycnals by the cyclonic circulation, an intense wind event inducedEkman pumping. The upwelled subsurface cold nutrient-rich water fertilized surface waters, characterized by an increase in Chl-a concentration. Prochlorococcus, pico-and nano-eukaryotes were more abundant in cold core waters while Synechococcus dominated in warm boundary waters. Nanoeukaryote were the main contributors

show abstract

The Impact of Submesoscale Physics on Primary Productivity of Plankton

Cited by 476 publications

References 108 publications

Controls of Multiple Stressors on the Black Sea Fishery

Controls of Multiple Stressors on the Black Sea Fishery

A Multiplatform Experiment to Unravel Meso- and Submesoscale Processes in an Intense Front (AlborEx)

Coupling physics and biogeochemistry thanks to high resolution observations of the phytoplankton community structure in the North-Western Mediterranean Sea

Contact Info

Product

Resources

About