Articles | Volume 27, issue 2
https://doi.org/10.5194/npg-27-277-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/npg-27-277-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
| 
19 May 2020
Research article | Highlight paper |
| 19 May 2020
| 19 May 2020
Effects of upwelling duration and phytoplankton growth regime on dissolved-oxygen levels in an idealized Iberian Peninsula upwelling system
João H. Bettencourt
CORRESPONDING AUTHOR
LEGOS, University of Toulouse, CNES, CNRS, IRD, UPS, 31400 Toulouse,
France
Vincent Rossi
MIO (UM 110, UMR 7294), CNRS, Aix-Marseille Université, Université Toulon, IRD,
13288 Marseille, France
Lionel Renault
LEGOS, University of Toulouse, CNES, CNRS, IRD, UPS, 31400 Toulouse,
France
Peter Haynes
Department of Applied Mathematics and Theoretical Physics, University
of Cambridge, Cambridge, UK
Yves Morel
LEGOS, University of Toulouse, CNES, CNRS, IRD, UPS, 31400 Toulouse,
France
Véronique Garçon
LEGOS, University of Toulouse, CNES, CNRS, IRD, UPS, 31400 Toulouse,
France
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Sébastien Masson, Swen Jullien, Eric Maisonnave, David Gill, Guillaume Samson, Mathieu Le Corre, and Lionel Renault
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2024-140, https://doi.org/10.5194/gmd-2024-140, 2024
Revised manuscript accepted for GMD
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This article details a new feature we implemented in the most popular regional atmospheric model (WRF). This feature allows data to be exchanged between WRF and any other model (e.g. an ocean model) using the coupling library Ocean-Atmosphere-Sea-Ice-Soil – Model Coupling Toolkit (OASIS3-MCT). This coupling interface is designed to be non-intrusive, flexible and modular. It also offers the possibility of taking into account the nested zooms used in WRF or in the models with which it is coupled.
Marine Di Stefano, David Nerini, Itziar Alvarez, Giandomenico Ardizzone, Patrick Astruch, Gotzon Basterretxea, Aurélie Blanfuné, Denis Bonhomme, Antonio Calò, Ignacio Catalan, Carlo Cattano, Adrien Cheminée, Romain Crec'hriou, Amalia Cuadros, Antonio Di Franco, Carlos Diaz-Gil, Tristan Estaque, Robin Faillettaz, Fabiana C. Félix-Hackradt, José Antonio Garcia-Charton, Paolo Guidetti, Loïc Guilloux, Jean-Georges Harmelin, Mireille Harmelin-Vivien, Manuel Hidalgo, Hilmar Hinz, Jean-Olivier Irisson, Gabriele La Mesa, Laurence Le Diréach, Philippe Lenfant, Enrique Macpherson, Sanja Matić-Skoko, Manon Mercader, Marco Milazzo, Tiffany Monfort, Joan Moranta, Manuel Muntoni, Matteo Murenu, Lucie Nunez, M. Pilar Olivar, Jérémy Pastor, Ángel Pérez-Ruzafa, Serge Planes, Nuria Raventos, Justine Richaume, Elodie Rouanet, Erwan Roussel, Sandrine Ruitton, Ana Sabatés, Thierry Thibaut, Daniele Ventura, Laurent Vigliola, Dario Vrdoljak, and Vincent Rossi
Earth Syst. Sci. Data, 16, 3851–3871, https://doi.org/10.5194/essd-16-3851-2024, https://doi.org/10.5194/essd-16-3851-2024, 2024
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We build a compilation of early-life dispersal traits for coastal fish species. The database contains over 110 000 entries collected from 1993 to 2021 in the western Mediterranean. All observations are harmonized to provide information on dates and locations of spawning and settlement, along with pelagic larval durations. When applicable, missing data are reconstructed from dynamic energy budget theory. Statistical analyses reveal sampling biases across taxa, space and time.
Elisa Carli, Rosemary Morrow, Oscar Vergara, Robin Chevrier, and Lionel Renault
Ocean Sci., 19, 1413–1435, https://doi.org/10.5194/os-19-1413-2023, https://doi.org/10.5194/os-19-1413-2023, 2023
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Oceanic eddies are the structures carrying most of the energy in our oceans. They are key to climate regulation and nutrient transport. We prepare for the Surface Water and Ocean Topography mission, studying eddy dynamics in the region south of Africa, where the Indian and Atlantic oceans meet, using models and simulated satellite data. SWOT will provide insights into the structures smaller than what is currently observable, which appear to greatly contribute to eddy kinetic energy and strain.
Michel Tchilibou, Ariane Koch-Larrouy, Simon Barbot, Florent Lyard, Yves Morel, Julien Jouanno, and Rosemary Morrow
Ocean Sci., 18, 1591–1618, https://doi.org/10.5194/os-18-1591-2022, https://doi.org/10.5194/os-18-1591-2022, 2022
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This high-resolution model-based study investigates the variability in the generation, propagation, and sea height signature (SSH) of the internal tide off the Amazon shelf during two contrasted seasons. ITs propagate further north during the season characterized by weak currents and mesoscale eddies and a shallow and strong pycnocline. IT imprints on SSH dominate those of the geostrophic motion for horizontal scales below 200 km; moreover, the SSH is mainly incoherent below 70 km.
Hector S. Torres, Patrice Klein, Jinbo Wang, Alexander Wineteer, Bo Qiu, Andrew F. Thompson, Lionel Renault, Ernesto Rodriguez, Dimitris Menemenlis, Andrea Molod, Christopher N. Hill, Ehud Strobach, Hong Zhang, Mar Flexas, and Dragana Perkovic-Martin
Geosci. Model Dev., 15, 8041–8058, https://doi.org/10.5194/gmd-15-8041-2022, https://doi.org/10.5194/gmd-15-8041-2022, 2022
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Wind work at the air-sea interface is the scalar product of winds and currents and is the transfer of kinetic energy between the ocean and the atmosphere. Using a new global coupled ocean-atmosphere simulation performed at kilometer resolution, we show that all scales of winds and currents impact the ocean dynamics at spatial and temporal scales. The consequential interplay of surface winds and currents in the numerical simulation motivates the need for a winds and currents satellite mission.
Bjorn Stevens, Sandrine Bony, David Farrell, Felix Ament, Alan Blyth, Christopher Fairall, Johannes Karstensen, Patricia K. Quinn, Sabrina Speich, Claudia Acquistapace, Franziska Aemisegger, Anna Lea Albright, Hugo Bellenger, Eberhard Bodenschatz, Kathy-Ann Caesar, Rebecca Chewitt-Lucas, Gijs de Boer, Julien Delanoë, Leif Denby, Florian Ewald, Benjamin Fildier, Marvin Forde, Geet George, Silke Gross, Martin Hagen, Andrea Hausold, Karen J. Heywood, Lutz Hirsch, Marek Jacob, Friedhelm Jansen, Stefan Kinne, Daniel Klocke, Tobias Kölling, Heike Konow, Marie Lothon, Wiebke Mohr, Ann Kristin Naumann, Louise Nuijens, Léa Olivier, Robert Pincus, Mira Pöhlker, Gilles Reverdin, Gregory Roberts, Sabrina Schnitt, Hauke Schulz, A. Pier Siebesma, Claudia Christine Stephan, Peter Sullivan, Ludovic Touzé-Peiffer, Jessica Vial, Raphaela Vogel, Paquita Zuidema, Nicola Alexander, Lyndon Alves, Sophian Arixi, Hamish Asmath, Gholamhossein Bagheri, Katharina Baier, Adriana Bailey, Dariusz Baranowski, Alexandre Baron, Sébastien Barrau, Paul A. Barrett, Frédéric Batier, Andreas Behrendt, Arne Bendinger, Florent Beucher, Sebastien Bigorre, Edmund Blades, Peter Blossey, Olivier Bock, Steven Böing, Pierre Bosser, Denis Bourras, Pascale Bouruet-Aubertot, Keith Bower, Pierre Branellec, Hubert Branger, Michal Brennek, Alan Brewer, Pierre-Etienne Brilouet, Björn Brügmann, Stefan A. Buehler, Elmo Burke, Ralph Burton, Radiance Calmer, Jean-Christophe Canonici, Xavier Carton, Gregory Cato Jr., Jude Andre Charles, Patrick Chazette, Yanxu Chen, Michal T. Chilinski, Thomas Choularton, Patrick Chuang, Shamal Clarke, Hugh Coe, Céline Cornet, Pierre Coutris, Fleur Couvreux, Susanne Crewell, Timothy Cronin, Zhiqiang Cui, Yannis Cuypers, Alton Daley, Gillian M. Damerell, Thibaut Dauhut, Hartwig Deneke, Jean-Philippe Desbios, Steffen Dörner, Sebastian Donner, Vincent Douet, Kyla Drushka, Marina Dütsch, André Ehrlich, Kerry Emanuel, Alexandros Emmanouilidis, Jean-Claude Etienne, Sheryl Etienne-Leblanc, Ghislain Faure, Graham Feingold, Luca Ferrero, Andreas Fix, Cyrille Flamant, Piotr Jacek Flatau, Gregory R. Foltz, Linda Forster, Iulian Furtuna, Alan Gadian, Joseph Galewsky, Martin Gallagher, Peter Gallimore, Cassandra Gaston, Chelle Gentemann, Nicolas Geyskens, Andreas Giez, John Gollop, Isabelle Gouirand, Christophe Gourbeyre, Dörte de Graaf, Geiske E. de Groot, Robert Grosz, Johannes Güttler, Manuel Gutleben, Kashawn Hall, George Harris, Kevin C. Helfer, Dean Henze, Calvert Herbert, Bruna Holanda, Antonio Ibanez-Landeta, Janet Intrieri, Suneil Iyer, Fabrice Julien, Heike Kalesse, Jan Kazil, Alexander Kellman, Abiel T. Kidane, Ulrike Kirchner, Marcus Klingebiel, Mareike Körner, Leslie Ann Kremper, Jan Kretzschmar, Ovid Krüger, Wojciech Kumala, Armin Kurz, Pierre L'Hégaret, Matthieu Labaste, Tom Lachlan-Cope, Arlene Laing, Peter Landschützer, Theresa Lang, Diego Lange, Ingo Lange, Clément Laplace, Gauke Lavik, Rémi Laxenaire, Caroline Le Bihan, Mason Leandro, Nathalie Lefevre, Marius Lena, Donald Lenschow, Qiang Li, Gary Lloyd, Sebastian Los, Niccolò Losi, Oscar Lovell, Christopher Luneau, Przemyslaw Makuch, Szymon Malinowski, Gaston Manta, Eleni Marinou, Nicholas Marsden, Sebastien Masson, Nicolas Maury, Bernhard Mayer, Margarette Mayers-Als, Christophe Mazel, Wayne McGeary, James C. McWilliams, Mario Mech, Melina Mehlmann, Agostino Niyonkuru Meroni, Theresa Mieslinger, Andreas Minikin, Peter Minnett, Gregor Möller, Yanmichel Morfa Avalos, Caroline Muller, Ionela Musat, Anna Napoli, Almuth Neuberger, Christophe Noisel, David Noone, Freja Nordsiek, Jakub L. Nowak, Lothar Oswald, Douglas J. Parker, Carolyn Peck, Renaud Person, Miriam Philippi, Albert Plueddemann, Christopher Pöhlker, Veronika Pörtge, Ulrich Pöschl, Lawrence Pologne, Michał Posyniak, Marc Prange, Estefanía Quiñones Meléndez, Jule Radtke, Karim Ramage, Jens Reimann, Lionel Renault, Klaus Reus, Ashford Reyes, Joachim Ribbe, Maximilian Ringel, Markus Ritschel, Cesar B. Rocha, Nicolas Rochetin, Johannes Röttenbacher, Callum Rollo, Haley Royer, Pauline Sadoulet, Leo Saffin, Sanola Sandiford, Irina Sandu, Michael Schäfer, Vera Schemann, Imke Schirmacher, Oliver Schlenczek, Jerome Schmidt, Marcel Schröder, Alfons Schwarzenboeck, Andrea Sealy, Christoph J. Senff, Ilya Serikov, Samkeyat Shohan, Elizabeth Siddle, Alexander Smirnov, Florian Späth, Branden Spooner, M. Katharina Stolla, Wojciech Szkółka, Simon P. de Szoeke, Stéphane Tarot, Eleni Tetoni, Elizabeth Thompson, Jim Thomson, Lorenzo Tomassini, Julien Totems, Alma Anna Ubele, Leonie Villiger, Jan von Arx, Thomas Wagner, Andi Walther, Ben Webber, Manfred Wendisch, Shanice Whitehall, Anton Wiltshire, Allison A. Wing, Martin Wirth, Jonathan Wiskandt, Kevin Wolf, Ludwig Worbes, Ethan Wright, Volker Wulfmeyer, Shanea Young, Chidong Zhang, Dongxiao Zhang, Florian Ziemen, Tobias Zinner, and Martin Zöger
Earth Syst. Sci. Data, 13, 4067–4119, https://doi.org/10.5194/essd-13-4067-2021, https://doi.org/10.5194/essd-13-4067-2021, 2021
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The EUREC4A field campaign, designed to test hypothesized mechanisms by which clouds respond to warming and benchmark next-generation Earth-system models, is presented. EUREC4A comprised roughly 5 weeks of measurements in the downstream winter trades of the North Atlantic – eastward and southeastward of Barbados. It was the first campaign that attempted to characterize the full range of processes and scales influencing trade wind clouds.
Jacob W. Smith, Peter H. Haynes, Amanda C. Maycock, Neal Butchart, and Andrew C. Bushell
Atmos. Chem. Phys., 21, 2469–2489, https://doi.org/10.5194/acp-21-2469-2021, https://doi.org/10.5194/acp-21-2469-2021, 2021
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This paper informs realistic simulation of stratospheric water vapour by clearly attributing each of the two key influences on water vapour entry to the stratosphere. Presenting modified trajectory models, the results of this paper show temperatures dominate on annual and inter-annual variations; however, transport has a significant effect in reducing the annual cycle maximum. Furthermore, sub-seasonal variations in temperature have an important overall influence.
Mochamad Furqon Azis Ismail, Joachim Ribbe, Johannes Karstensen, and Vincent Rossi
Ocean Sci. Discuss., https://doi.org/10.5194/os-2018-142, https://doi.org/10.5194/os-2018-142, 2019
Publication in OS not foreseen
Marine Bretagnon, Aurélien Paulmier, Véronique Garçon, Boris Dewitte, Séréna Illig, Nathalie Leblond, Laurent Coppola, Fernando Campos, Federico Velazco, Christos Panagiotopoulos, Andreas Oschlies, J. Martin Hernandez-Ayon, Helmut Maske, Oscar Vergara, Ivonne Montes, Philippe Martinez, Edgardo Carrasco, Jacques Grelet, Olivier Desprez-De-Gesincourt, Christophe Maes, and Lionel Scouarnec
Biogeosciences, 15, 5093–5111, https://doi.org/10.5194/bg-15-5093-2018, https://doi.org/10.5194/bg-15-5093-2018, 2018
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In oxygen minimum zone, the fate of the organic matter is a key question as the low oxygen condition would preserve the OM and thus enhance the biological carbon pump while the high microbial activity would foster the remineralisation and the greenhouse gases emission. To investigate this paradigm, sediment traps were deployed off Peru. We pointed out the influence of the oxygenation as well as the organic matter quantity and quality on the carbon transfer efficiency in the oxygen minimum zone.
Mélanie Giraud, Véronique Garçon, Denis De La Broise, Stéphane L'Helguen, Joël Sudre, and Marie Boye
Biogeosciences Discuss., https://doi.org/10.5194/bg-2018-306, https://doi.org/10.5194/bg-2018-306, 2018
Manuscript not accepted for further review
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Associated to transitional
blueenergies, first investigation of the environmental impact on the marine microorganisms of an Ocean Thermal Energy Conversion (OTEC) pilot plant before its installation, using numerical simulation and in situ experimentations. No environmental standards are available yet. Microbiodiversity can be impacted in one scenario of the OTEC functioning. Give the basis for anticipating the long-term effects of renewable marine thermal energies on the environment.
Pedro Monroy, Emilio Hernández-García, Vincent Rossi, and Cristóbal López
Nonlin. Processes Geophys., 24, 293–305, https://doi.org/10.5194/npg-24-293-2017, https://doi.org/10.5194/npg-24-293-2017, 2017
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We study the problem of sinking particles in a realistic oceanic flow, with major energetic structures in the mesoscale, focussing on marine biogenic particles. By using a simplified equation of motion for small particles in a mesoscale velocity field, we estimate the influence of physical processes such as the Coriolis force and the particle's inertia, and we conclude that they represent negligible corrections to passive transport by the flow, with added vertical velocity due to gravity.
Alison Ming, Amanda C. Maycock, Peter Hitchcock, and Peter Haynes
Atmos. Chem. Phys., 17, 5677–5701, https://doi.org/10.5194/acp-17-5677-2017, https://doi.org/10.5194/acp-17-5677-2017, 2017
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This work quantifies the contribution of the seasonal changes in ozone and water vapour to the temperature cycle in a region of the atmosphere about ~ 18 km up in the tropics (the lower stratosphere). This region is important because most of the air entering the stratosphere does so through this region and temperature fluctuations there influence how much water vapour enters the stratosphere and hence the properties of the stratosphere.
Oscar Vergara, Boris Dewitte, Ivonne Montes, Veronique Garçon, Marcel Ramos, Aurélien Paulmier, and Oscar Pizarro
Biogeosciences, 13, 4389–4410, https://doi.org/10.5194/bg-13-4389-2016, https://doi.org/10.5194/bg-13-4389-2016, 2016
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The Southeast Pacific hosts one of the most extensive oxygen minimum zone (OMZ), yet the dynamics behind it remain unveiled. We use a high-resolution coupled physical–biogeochemical model to document the seasonal cycle of dissolved oxygen within the OMZ in both the coastal zone and the offshore ocean. The OMZ seasonal variability is driven by the seasonal fluctuations of the dissolved oxygen eddy flux, with a peak in Austral winter (fall) at the northern (southern) boundary and near the coast.
I. Hernández-Carrasco, J. Sudre, V. Garçon, H. Yahia, C. Garbe, A. Paulmier, B. Dewitte, S. Illig, I. Dadou, M. González-Dávila, and J. M. Santana-Casiano
Biogeosciences, 12, 5229–5245, https://doi.org/10.5194/bg-12-5229-2015, https://doi.org/10.5194/bg-12-5229-2015, 2015
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We have reconstructed maps of air-sea CO2 fluxes at high resolution (4 km) in the offshore Benguela region using sea surface temperature and ocean colour data and CarbonTracker CO2 fluxes data at low resolution (110 km).
The inferred representation of pCO2 improves the description provided by CarbonTracker, enhancing small-scale variability.
We find that the resolution, as well as the inferred pCO2 data itself, is closer to in situ measurements of pCO2.
Related subject area
Subject: Bifurcation, dynamical systems, chaos, phase transition, nonlinear waves, pattern formation | Topic: Climate, atmosphere, ocean, hydrology, cryosphere, biosphere | Techniques: Simulation
A robust numerical method for the generation and propagation of periodic finite-amplitude internal waves in natural waters using high-accuracy simulations
The role of time-varying external factors in the intensification of tropical cyclones
Transformation of internal solitary waves at the edge of ice cover
A new approach to understanding fluid mixing in process-study models of stratified fluids
Aggregation of slightly buoyant microplastics in 3D vortex flows
An approach for projecting the timing of abrupt winter Arctic sea ice loss
On the interaction of stochastic forcing and regime dynamics
Estimate of energy loss from internal solitary waves breaking on slopes
The effect of strong shear on internal solitary-like waves
Enhanced diapycnal mixing with polarity-reversing internal solitary waves revealed by seismic reflection data
Pierre Lloret, Peter J. Diamessis, Marek Stastna, and Greg N. Thomsen
Nonlin. Processes Geophys., 31, 515–533, https://doi.org/10.5194/npg-31-515-2024, https://doi.org/10.5194/npg-31-515-2024, 2024
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This study presents a new approach to simulating large ocean density waves that travel long distances without breaking down. This new approach ensures that these waves are depicted more accurately and realistically in our models. This is particularly useful for understanding wave behavior in lakes with distinct water layers, which can help predict natural phenomena and their effects on environments like swash zones, where waves meet the shore.
Samuel Watson and Courtney Quinn
Nonlin. Processes Geophys., 31, 381–394, https://doi.org/10.5194/npg-31-381-2024, https://doi.org/10.5194/npg-31-381-2024, 2024
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The intensification of tropical cyclones (TCs) is explored through a conceptual model derived from geophysical principals. Focus is put on the behaviour of the model with parameters which change in time. The rates of change cause the model to either tip to an alternative stable state or recover the original state. This represents intensification, dissipation, or eyewall replacement cycles (ERCs). A case study which emulates the rapid intensification events of Hurricane Irma (2017) is explored.
Kateryna Terletska, Vladimir Maderich, and Elena Tobisch
Nonlin. Processes Geophys., 31, 207–217, https://doi.org/10.5194/npg-31-207-2024, https://doi.org/10.5194/npg-31-207-2024, 2024
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The transformation of internal waves at the edge of ice cover can enhance the turbulent mixing and melting of ice in the Arctic Ocean and Antarctica. We studied numerically the transformation of internal solitary waves of depression under smooth ice surfaces compared with the processes beneath the ridged underside of the ice. For large keels, more than 40% of wave energy is lost on the first keel, while for relatively small keels energy losses on the first keel are less than 6%.
Samuel George Hartharn-Evans, Marek Stastna, and Magda Carr
Nonlin. Processes Geophys., 31, 61–74, https://doi.org/10.5194/npg-31-61-2024, https://doi.org/10.5194/npg-31-61-2024, 2024
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Across much of the ocean, and the world's lakes, less dense water (either because it is warm or fresh) overlays denser water, forming stratification. The mixing of these layers affects the distribution of heat, nutrients, plankton, sediment, and buoyancy, so it is crucial to understand. We use small-scale numerical experiments to better understand these processes, and here we propose a new analysis tool for understanding mixing within those models, looking at where two variables intersect.
Irina I. Rypina, Lawrence J. Pratt, and Michael Dotzel
Nonlin. Processes Geophys., 31, 25–44, https://doi.org/10.5194/npg-31-25-2024, https://doi.org/10.5194/npg-31-25-2024, 2024
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This paper investigates the aggregation of small, spherical, slightly buoyant, rigid particles in a simple 3D vortex flow. Our goal was to gain insights into the behaviour of slightly buoyant marine microplastics in a flow that qualitatively resembles ocean eddies. Attractors are mapped out for the steady, axisymmetric; steady, asymmetric; and nonsteady, asymmetric vortices over a range of flow and particle parameters. Simple theoretical arguments are used to interpret the results.
Camille Hankel and Eli Tziperman
Nonlin. Processes Geophys., 30, 299–309, https://doi.org/10.5194/npg-30-299-2023, https://doi.org/10.5194/npg-30-299-2023, 2023
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We present a novel, efficient method for identifying climate
tipping pointthreshold values of CO2 beyond which rapid and irreversible changes occur. We use a simple model of Arctic sea ice to demonstrate the method’s efficacy and its potential for use in state-of-the-art global climate models that are too expensive to run for this purpose using current methods. The ability to detect tipping points will improve our preparedness for rapid changes that may occur under future climate change.
Joshua Dorrington and Tim Palmer
Nonlin. Processes Geophys., 30, 49–62, https://doi.org/10.5194/npg-30-49-2023, https://doi.org/10.5194/npg-30-49-2023, 2023
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Atmospheric models often include random forcings, which aim to replicate the impact of processes too small to be resolved. Recent results in simple atmospheric models suggest that this random forcing can actually stabilise certain slow-varying aspects of the system, which could provide a path for resolving known errors in our models. We use randomly forced simulations of a
toychaotic system and theoretical arguments to explain why this strange effect occurs – at least in simple models.
Kateryna Terletska and Vladimir Maderich
Nonlin. Processes Geophys., 29, 161–170, https://doi.org/10.5194/npg-29-161-2022, https://doi.org/10.5194/npg-29-161-2022, 2022
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Internal solitary waves (ISWs) emerge in the ocean and seas in various forms and break on the shelf zones in a variety of ways. This results in intensive mixing that affects processes such as biological productivity and sediment transport. Mechanisms of wave interaction with slopes are related to breaking and changing polarity. Our study focuses on wave transformation over idealized shelf-slope topography using a two-layer stratification. Four types of ISW transformation over slopes are shown.
Marek Stastna, Aaron Coutino, and Ryan K. Walter
Nonlin. Processes Geophys., 28, 585–598, https://doi.org/10.5194/npg-28-585-2021, https://doi.org/10.5194/npg-28-585-2021, 2021
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Large-amplitude waves in the interior of the ocean-internal waves in the ocean propagate in a dynamic, highly variable environment with changes in background current, local depth, and stratification. These waves have a well-known mathematical theory that, despite considerable progress, has some gaps. In particular, waves have been observed in situations that preclude an application of the mathematical theory. We present numerical simulations of the spontaneous generation of such waves.
Yi Gong, Haibin Song, Zhongxiang Zhao, Yongxian Guan, Kun Zhang, Yunyan Kuang, and Wenhao Fan
Nonlin. Processes Geophys., 28, 445–465, https://doi.org/10.5194/npg-28-445-2021, https://doi.org/10.5194/npg-28-445-2021, 2021
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When the internal solitary wave propagates to the continental shelf and slope, the polarity reverses due to the shallower water depth. In this process, the internal solitary wave dissipates energy and enhances diapycnal mixing, thus affecting the local oceanic environment. In this study, we used reflection seismic data to evaluate the spatial distribution of the diapycnal mixing around the polarity-reversing internal solitary waves.
Cited articles
Adams, K. A., Barth, J. A., and Chan, F.: Temporal variability of near-bottom
dissolved oxygen during upwelling off central Oregon, J. Geophys.
Res.-Oceans, 118, 4839–4854, https://doi.org/10.1002/jgrc.20361, 2013.
Álvarez-Salgado, X. A., Rosón, G., Pérez, F. F., and Pazos, Y.:
Hydrographic variability off the Rías Baixas (NW Spain) during the
upwelling season, J. Geophys. Res., 98, 14447,
https://doi.org/10.1029/93JC00458, 1993.
Álvarez-Salgado, X. A., Nieto-Cid, M., Álvarez, M., Pérez, F. F.,
Morin, P., and Mercier, H.: New insights on the mineralization of dissolved
organic matter in central, intermediate, and deep water masses of the
northeast North Atlantic, Limnol. Oceanogr., 58, 681–696,
https://doi.org/10.4319/lo.2013.58.2.0681, 2013.
Behrenfeld, M. J., Halsey Kimberly, H., and Milligan Allen, J.: Evolved
physiological responses of phytoplankton to their integrated growth
environment, Philos. T. R. Soc. B, 363, 2687–2703, https://doi.org/10.1098/rstb.2008.0019, 2008.
Bettencourt, J. H., López, C., Hernández-García, E., Montes,
I., Sudre, J., Dewitte, B., Paulmier, A., and Garçon, V.: Boundaries of
the Peruvian oxygen minimum zone shaped by coherent mesoscale dynamics,
Nat. Geosci., 8, 937–940, https://doi.org/10.1038/ngeo2570, 2015.
Bettencourt, J. H., Rossi, V., Hernández-García, E., Marta-Almeida,
M., and López, C.: Characterization of the Structure and Cross-Shore
Transport Properties of a Coastal Upwelling Filament Using Three-Dimensional
Finite-Size Lyapunov Exponents, J. Geophys. Res.-Oceans,
122, 7433–7448, https://doi.org/10.1002/2017JC012700, 2017.
Boyer, T. P., Antonov, J. I., Baranova, O. K., Garcia, H. E., Johnson, D. R., Mishonov, A. V., O'Brien, T. D., Seidov, D., Smolyar, I., Zweng, M. M., Paver, C. R., Locarnini, R. A., Reagan, J. R., Forgy, C., Grodsky, A., and Levitus, S.: World ocean Database 2013, edited by Ocean Climate Laboratory – National Oceanographic Data Center (Silver Spring, MD, US), https://doi.org/10.7289/V5NZ85MT, 2013.
Breitburg, D., Levin, L. A., Oschlies, A., Grégoire, M., Chavez, F. P.,
Conley, D. J., Garçon, V., Gilbert, D., Gutiérrez, D., Isensee, K.,
Jacinto, G. S., Limburg, K. E., Montes, I., Naqvi, S. W. A., Pitcher, G. C.,
Rabalais, N. N., Roman, M. R., Rose, K. A., Seibel, B. A., Telszewski, M.,
Yasuhara, M., and Zhang, J.: Declining Oxygen in the Global Ocean and Coastal
Waters, Science, 359, eaam7240, https://doi.org/10.1126/science.aam7240, 2018.
Breitburg, D. L., Loher, T., Pacey, C. A., and Gerstein, A.: Varying Effects
of Low Dissolved Oxygen on Trophic Interactions in an Estuarine Food Web,
Ecol. Monogr., 67, 489–507, https://doi.org/10.2307/2963467, 1997.
Capet, X., McWilliams, J., Molemaker, M., and Shchepetkin, A.: Mesoscale to
Submesoscale Transition in the California Current System. Part I: Flow
Structure, Eddy Flux, and Observational Tests, J. Phys.
Oceanogr., 38, 29–43, 2008.
Capet, A., Meysman, F. J. R., Akoumianaki, I., Soetaert, K., and Grégoire, M.:
Integrating sediment biogeochemistry into 3D oceanic models: A study of
benthic-pelagic coupling in the Black Sea, Ocean Model., 101, 83–100,
https://doi.org/10.1016/j.ocemod.2016.03.006, 2016.
Castaing, B., Gagne, Y., and Hopfinger, E. J.: Velocity Probability Density
Functions of High Reynolds Number Turbulence, Physica D, 46, 177–200, https://doi.org/10.1016/0167-2789(90)90035-N, 1990.
Castro, C. G., Nieto-Cid, M., Álvarez-Salgado, X. A., and Pérez, F. F.:
Local remineralization patterns in the mesopelagic zone of the Eastern North
Atlantic, off the NW Iberian Peninsula, Deep-Sea Res. Pt. I, 53, 1925–1940,
https://doi.org/10.1016/j.dsr.2006.09.002, 2006.
Cerovečki, I., Plumb, R. A., and Heres, W.: Eddy Transport and Mixing in
a Wind- and Buoyancy-Driven Jet on the Sphere, J. Phys.
Oceanogr., 39, 1133–1149, https://doi.org/10.1175/2008JPO3596.1, 2009.
Chaigneau, A., Eldin, G., and Dewitte, B.: Eddy Activity in the Four Major
Upwelling Systems from Satellite Altimetry (1992–2007), Prog.
Oceanogr., 83, 117–123, https://doi.org/10.1016/j.pocean.2009.07.012, 2009.
Charney, J. G.: Geostrophic Turbulence, J. Atmos. Sci.,
28, 1087–1095, https://doi.org/10.1175/1520-0469(1971)028<1087:GT>2.0.CO;2, 1971.
Combes, V., Chenillat, F., Lorenzo, E. D., Rivière, P., Ohman, M. D., and
Bograd, S. J.: Cross-Shore Transport Variability in the California Current:
Ekman Upwelling vs. Eddy Dynamics, Prog. Oceanogr., 109, 78–89,
https://doi.org/10.1016/j.pocean.2012.10.001, 2013.
Debreu, L., Marchesiello, P., Penven, P., and Cambon, G.: Two-Way Nesting in
Split-Explicit Ocean Models: Algorithms, Implementation and Validation,
Ocean Model., 49, 1–21, 2012.
Diaz, R. J. and Rosenberg, R.: Spreading Dead Zones and Consequences for
Marine Ecosystems, Science, 321, 926–929,
https://doi.org/10.1126/science.1156401, 2008.
Durski, S. M. and Allen, J. S.: Finite-Amplitude Evolution of Instabilities
Associated with the Coastal Upwelling Front, J. Phys.
Oceanogr., 35, 1606–1628, https://doi.org/10.1175/JPO2762.1, 2005.
Durski, S. M., Allen, J. S., Egbert, G. D., and Samelson, R. M.: Scale
Evolution of Finite-Amplitude Instabilities on a Coastal Upwelling Front,
J. Phys. Oceanogr., 37, 837–854, https://doi.org/10.1175/JPO2994.1,
2007.
Feng, Y., DiMarco, S. F., and Jackson, G. A.: Relative role of wind forcing
and riverine nutrient input on the extent of hypoxia in the northern Gulf of
Mexico, Geophys. Res. Lett., 39, L09601,
https://doi.org/10.1029/2012GL051192, 2012.
Forrest, D. R., Hetland, R. D., and DiMarco, S. F.: Multivariable statistical
regression models of the areal extent of hypoxia over the Texas–Louisiana
continental shelf, Environ. Res. Lett., 6, 045002,
https://doi.org/10.1088/1748-9326/6/4/045002, 2011.
Gilly, W. F., Beman, J. M., Litvin, S. Y., and Robison, B. H.: Oceanographic
and Biological Effects of Shoaling of the Oxygen Minimum Zone, Annu. Rev.
Marine Sci., 5, 393–420, https://doi.org/10.1146/annurev-marine-120710-100849,
2013.
Gomes, H. do R., Goes, J. I., Matondkar, S. G. P., Buskey, E. J., Basu, S.,
Parab, S., and Thoppil, P.: Massive outbreaks of Noctiluca scintillans blooms in the Arabian Sea
due to spread of hypoxia, Nat. Commun., 5, 4862,
https://doi.org/10.1038/ncomms5862, 2014.
Grantham, B. A., Chan, F., Nielsen, K. J., Fox, D. S., Barth, J. A., Huyer,
A., Lubchenco, J., and Menge, B. A.: Upwelling-Driven Nearshore Hypoxia
Signals Ecosystem and Oceanographic Changes in the Northeast Pacific,
Nature, 429, nature02605, https://doi.org/10.1038/nature02605, 2004.
Gregg, W. W., Rousseaux, C. S., and Franz, B. A.: Global trends in ocean
phytoplankton: a new assessment using revised ocean colour data, Remote
Sens. Lett., 8, 1102–1111, https://doi.org/10.1080/2150704X.2017.1354263, 2017.
Gruber, N., Lachkar, Z., Frenzel, H., Marchesiello, P., Munnich, M.,
McWilliams, J., Nagai, T., and Plattner, G.: Eddy-Induced Reduction of
Biological Production in Eastern Boundary Upwelling Systems, Nat.
Geosci., 4, 787–792, https://doi.org/10.1038/NGEO1273, 2011.
Gutknecht, E., Dadou, I., Le Vu, B., Cambon, G., Sudre, J., Garçon, V., Machu, E., Rixen, T., Kock, A., Flohr, A., Paulmier, A., and Lavik, G.: Coupled physical/biogeochemical modeling including O2-dependent processes in the Eastern Boundary Upwelling Systems: application in the Benguela, Biogeosciences, 10, 3559–3591, https://doi.org/10.5194/bg-10-3559-2013, 2013.
Hales, B., Karp-Boss, L., Perlin, A., and Wheeler, P. A.: Oxygen Production
and Carbon Sequestration in an Upwelling Coastal Margin, Global
Biogeochem. Cycles, 20, GB3001, https://doi.org/10.1029/2005GB002517, 2006.
Harris, G. P.: Phytoplankton Ecology, Springer Netherlands, Dordrecht,
1986.
Head, E. J. H. and Pepin, P.: Spatial and inter-decadal variability in
plankton abundance and composition in the Northwest Atlantic (1958–2006), J.
Plankton Res., 32, 1633–1648, https://doi.org/10.1093/plankt/fbq090, 2010.
Hernández-Carrasco, I., Rossi, V., Hernández-García, E.,
Garçon, V., and López, C.: The Reduction of Plankton Biomass Induced
by Mesoscale Stirring: A Modeling Study in the Benguela Upwelling, Deep-Sea
Res. Pt. I, 83, 65–80,
https://doi.org/10.1016/j.dsr.2013.09.003, 2014.
Laffoley, D. and Baxter, J.: Ocean deoxygenation: everyone's problem:
causes, impacts, consequences and solutions, IUCN Report, Gland,
Switzerland, 562 pp., https://doi.org/10.2305/IUCN.CH.2019.13.en, 2019.
Large, W. G., McWilliams, J. C., and Doney, S. C.: Oceanic Vertical Mixing: A
Review and a Model with a Nonlocal Boundary Layer Parameterization, Rev. Geophys., 32, 363–403, 1994.
López-Sandoval, D. C., Rodríguez-Ramos, T., Cermeño, P.,
Sobrino, C., and Marañón, E.: Photosynthesis and respiration in
marine phytoplankton: Relationship with cell size, taxonomic affiliation,
and growth phase, J. Exp. Mar. Biol. Ecol., 457,
151–159, https://doi.org/10.1016/j.jembe.2014.04.013, 2014.
Lovecchio, E., Gruber, N., Münnich, M., and Lachkar, Z.: On the long-range offshore transport of organic carbon from the Canary Upwelling System to the open North Atlantic, Biogeosciences, 14, 3337–3369, https://doi.org/10.5194/bg-14-3337-2017, 2017.
Mackey, K. R. M., Paytan, A., Grossman, A. R., and Bailey, S.: A
photosynthetic strategy for coping in a high-light, low-nutrient
environment, Limnol. Oceanogr., 53, 900–913,
https://doi.org/10.4319/lo.2008.53.3.0900, 2008.
Mahaffey, C.: The conundrum of marine N2 fixation, Am. J.
Sci., 305, 546–595, https://doi.org/10.2475/ajs.305.6-8.546, 2005.
Marchesiello, P., McWilliams, J. C., and Shchepetkin, A.: Equilibrium
Structure and Dynamics of the California Current System, J. Phys. Oceanogr.,
33, 753–783, https://doi.org/10.1175/1520-0485(2003)33<753:ESADOT>2.0.CO;2, 2003.
Marta-Almeida, M., Reboreda, R., Rocha, C., Dubert, J., Nolasco, R.,
Cordeiro, N., Luna, T., Rocha, A., e Silva, J. D. L., Queiroga, H., Peliz,
A., and Ruiz-Villarreal, M.: Towards Operational Modeling and Forecasting of
the Iberian Shelves Ecosystem, PLOS ONE, 7, e37343,
https://doi.org/10.1371/journal.pone.0037343, 2012.
McClatchie, S., Goericke, R., Cosgrove, R., Auad, G., and Vetter, R.: Oxygen
in the Southern California Bight: Multidecadal trends and implications for
demersal fisheries, Geophys. Res. Lett., 37, L19602,
https://doi.org/10.1029/2010GL044497, 2010.
Miranda, P. M. A., Alves, J. M. R., and Serra, N.: Climate change and
upwelling: response of Iberian upwelling to atmospheric forcing in a
regional climate scenario, Clim. Dynam., 40, 2813–2824,
https://doi.org/10.1007/s00382-012-1442-9, 2013.
Moncoiffé, G., Álvarez-Salgado, X. A., Figueiras, F. G., and Savidge, G.:
Seasonal and short-time-scale dynamics of microplankton community production
and respiration in an inshore upwelling system, Marine Eco. Prog.
Ser., 196, 111–126, https://doi.org/10.3354/meps196111, 2000.
Montes, I., Dewitte, B., Gutknecht, E., Paulmier, A., Dadou, I., Oschlies,
A., and Garçon, V.: High-Resolution Modeling of the Eastern Tropical
Pacific Oxygen Minimum Zone: Sensitivity to the Tropical Oceanic
Circulation, J. Geophys. Res.-Oceans, 119, 5515–5532,
https://doi.org/10.1002/2014JC009858, 2014.
Nagai, T., Gruber, N., Frenzel, H., Lachkar, Z., McWilliams, J. C., and
Plattner, G.-K.: Dominant Role of Eddies and Filaments in the Offshore
Transport of Carbon and Nutrients in the California Current System, J. Geophys. Res.-Oceans, 120, 5318–5341,
https://doi.org/10.1002/2015JC010889, 2015.
Paulmier, A. and Ruiz-Pino, D.: Oxygen Minimum Zones (OMZs) in the Modern
Ocean, Prog. Oceanogr., 80, 113–128, 2009.
Pérez, F. F., Castro, C. G., Álvarez-Salgado, X. A., Ríos, A. F.:
Coupling between the Iberian basin – scale circulation and the Portugal
boundary current system: a chemical study, Deep-Sea Res. Pt. I, 48, 1519–1533,
https://doi.org/10.1016/S0967-0637(00)00101-1, 2001.
Petrovskii, S., Sekerci, Y., and Venturino, E.: Regime shifts and ecological
catastrophes in a model of plankton-oxygen dynamics under the climate
change, J. Theor. Biol., 424, 91–109,
https://doi.org/10.1016/j.jtbi.2017.04.018, 2017.
Plumb, R. A. and Ferrari, R.: Transformed Eulerian-Mean Theory. Part I:
Nonquasigeostrophic Theory for Eddies on a Zonal-Mean Flow, J.
Phys. Oceanogr., 35, 165–174, https://doi.org/10.1175/JPO-2669.1, 2005.
Reboreda, R., Cordeiro, N. G. F., Nolasco, R., Castro, C. G.,
Álvarez-Salgado, X. A., Queiroga, H., and Dubert, J.: Modeling the
Seasonal and Interannual Variability (2001–2010) of Chlorophyll-a in the
Iberian Margin, J. Sea Res., 93, 133–149,
https://doi.org/10.1016/j.seares.2014.04.003, 2014.
Reboreda, R., Castro, C. G., Álvarez-Salgado, X. A., Nolasco, R.,
Cordeiro, N. G. F., Queiroga, H., and Dubert, J.: Oxygen in the Iberian
Margin: A Modeling Study, Prog. Oceanogr., 131, 1–20,
https://doi.org/10.1016/j.pocean.2014.09.005, 2015.
Renault, L., Deutsch, C., McWilliams, J. C., Frenzel, H., Liang, J.-H., and
Colas, F.: Partial Decoupling of Primary Productivity from Upwelling in the
California Current System, Nat. Geosci., 9, 505–508,
https://doi.org/10.1038/ngeo2722, 2016.
Roegner, G. C., Needoba, J. A., and Baptista, A. M.: Coastal Upwelling
Supplies Oxygen-Depleted Water to the Columbia River Estuary, PLOS ONE,
6, e18672, https://doi.org/10.1371/journal.pone.0018672, 2011.
Rossi, V., Morel, Y., and Garçon, V.: Effect of the Wind on the Shelf
Dynamics: Formation of a Secondary Upwelling along the Continental Margin,
Ocean Model., 31, 51–79, 2010.
Rossi, V., Garçon, V., Tassel, J., Romagnan, J.-B., Stemmann, L.,
Jourdin, F., Morin, P., and Morel, Y.: Cross-Shelf Variability in the Iberian
Peninsula Upwelling System: Impact of a Mesoscale Filament, Cont.
Shelf Res., 59, 97–114, 2013.
Rykaczewski, R. R., Dunne, J. P., Sydeman, W. J., García-Reyes, M.,
Black, B. A., and Bograd, S. J.: Poleward displacement of coastal
upwelling-favorable winds in the ocean's eastern boundary currents through
the 21st century, Geophys. Res. Lett., 42, 6424–6431,
https://doi.org/10.1002/2015GL064694, 2015.
Sarthou, G., Timmermans, K. R., Blain, S., and Tréguer, P.: Growth physiology
and fate of diatoms in the ocean: a review, J. Sea Res., 53, 25–42, https://doi.org/10.1016/j.seares.2004.01.007, 2005.
Sekerci, Y. and Petrovskii, S.: Mathematical Modelling of Plankton–Oxygen
Dynamics under the Climate Change, B. Math. Biol., 77,
2325–2353, 2015.
Shchepetkin, A. F.: An Adaptive, Courant-Number-Dependent Implicit Scheme
for Vertical Advection in Oceanic Modeling, Ocean Model., 91, 38–69,
https://doi.org/10.1016/j.ocemod.2015.03.006, 2015.
Shchepetkin, A. F. and McWilliams, J. C.: The Regional Oceanic Modeling
System (ROMS): A Split-Explicit, Free-Surface,
Topography-Following-Coordinate Oceanic Model, Ocean Model., 9,
347–404, https://doi.org/10.1016/j.ocemod.2004.08.002, 2005.
Siedlecki, S. A., Banas, N. S., Davis, K. A., Giddings, S., Hickey, B. M.,
MacCready, P., Connolly, T., and Geier, S.: Seasonal and interannual oxygen
variability on the Washington and Oregon continental shelves, J. Geophys. Res.-Oceans, 120, 608–633, https://doi.org/10.1002/2014JC010254,
2015.
Sousa, M. C., deCastro, M., Alvarez, I., Gomez-Gesteira, M., and Dias, J. M.:
Why coastal upwelling is expected to increase along the western Iberian
Peninsula over the next century?, Sci. Total Environ., 592,
243–251, https://doi.org/10.1016/j.scitotenv.2017.03.046, 2017.
Stramma, L., Johnson, G. C., Sprintall, J., and Mohrholz, V.: Expanding
Oxygen-Minimum Zones in the Tropical Oceans, Science, 320, 655–658,
https://doi.org/10.1126/science.1153847, 2008.
Sydeman, W. J., García-Reyes, M., Schoeman, D. S., Rykaczewski, R. R.,
Thompson, S. A., Black, B. A., and Bograd, S. J.: Climate change and wind
intensification in coastal upwelling ecosystems, Science, 345, 77–80,
https://doi.org/10.1126/science.1251635, 2014.
Torres, R., Barton, E. D., Miller, P., and Fanjul, E.: Spatial patterns of
wind and sea surface temperature in the Galician upwelling region, J. Geophys. Res.-Oceans, 108, 3130, https://doi.org/10.1029/2002JC001361, 2003.
Turner, J. and Brittain, E.: Oxygen as a Factor In Photosynthesis, Biol. Rev., 37, 130–170, https://doi.org/10.1111/j.1469-185X.1962.tb01607.x, 1962.
Vaquer-Sunyer, R. and Duarte, C.: Thresholds of Hypoxia for Marine
Biodiversity, P. Natl. Acad. Sci. USA, 105, 15452–15457, https://doi.org/10.1073/pnas.0803833105, 2008.
Vergara, O., Dewitte, B., Montes, I., Garçon, V., Ramos, M., Paulmier, A., and Pizarro, O.: Seasonal variability of the oxygen minimum zone off Peru in a high-resolution regional coupled model, Biogeosciences, 13, 4389–4410, https://doi.org/10.5194/bg-13-4389-2016, 2016.
Wang, D., Gouhier, T. C., Menge, B. A., and Ganguly, A. R.: Intensification
and spatial homogenization of coastal upwelling under climate change,
Nature, 518, 390–394, https://doi.org/10.1038/nature14235, 2015.
Wanninkhof, R.: Relationship between wind speed and gas exchange over the
ocean, J. Geophys. Res., 97, 7373, https://doi.org/10.1029/92JC00188,
1992.
Wooster, W. S., Bakun, A., and McLain, D. R.: Seasonal upwelling cycle along
the eastern boundary of the North Atlantic, J. Mar. Res., 34, 131–141,
1976.
Wright, J. J., Konwar, K. M., and Hallam, S. J.: Microbial Ecology of
Expanding Oxygen Minimum Zones, Nat. Rev. Microb., 10, 381–394,
https://doi.org/10.1038/nrmicro2778, 2012.
Zehr, J. P. and Kudela, R. M.: Photosynthesis in the Open Ocean, Science,
326, 945–946, https://doi.org/10.1126/science.1181277, 2009.
Zhai, L., Platt, T., Tang, C., Sathyendranath, S., and Walne, A.: The
response of phytoplankton to climate variability associated with the North
Atlantic Oscillation, Deep-Sea Res. Pt. II, 93, 159–168, https://doi.org/10.1016/j.dsr2.2013.04.009, 2013.
Zhang, H., Cheng, W., Chen, Y., Yu, L., and Gong, W.: Controls on the
interannual variability of hypoxia in a subtropical embayment and its
adjacent waters in the Guangdong coastal upwelling system, northern South
China Sea, Ocean Dynam., 68, 923–938, https://doi.org/10.1007/s10236-018-1168-2,
2018.
Short summary
The oceans are losing oxygen, and future changes may worsen this problem. We performed computer simulations of an idealized Iberian Peninsula upwelling system to identify the main fine-scale processes driving dissolved oxygen variability as well as study the response of oxygen levels to changes in wind patterns and phytoplankton species. Our results suggest that oxygen levels would decrease if the wind blows for long periods of time or if phytoplankton is dominated by species that grow slowly.
The oceans are losing oxygen, and future changes may worsen this problem. We performed computer...
