Articles | Volume 18, issue 2
https://doi.org/10.5194/os-18-549-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-18-549-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Weakening and warming of the European Slope Current since the late 1990s attributed to basin-scale density changes
Ocean and Earth Science, University of Southampton Waterfront Campus, National Oceanography Centre, European Way, Southampton, SO14 3ZH, UK
Robert Marsh
Ocean and Earth Science, University of Southampton Waterfront Campus, National Oceanography Centre, European Way, Southampton, SO14 3ZH, UK
James Harle
National Oceanography Centre, European Way, Southampton, SO14 3ZH, UK
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This preprint is open for discussion and under review for Weather and Climate Dynamics (WCD).
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We studied marine heatwaves in the North Indian Ocean using sea surface temperatures with long-term warming removed to capture true short-term extremes. These heatwaves often interact with the monsoon's natural wet–dry cycles (MISO), shaping rainfall during and after events. After termination, extreme rainfall anomalies appear over parts of South Asia as revived monsoon winds release stored ocean heat and moisture.
Robert J. Wilson, Yuri Artioli, Giovanni Galli, James Harle, Jason Holt, Ana M. Queirós, and Sarah Wakelin
Ocean Sci., 21, 1255–1270, https://doi.org/10.5194/os-21-1255-2025, https://doi.org/10.5194/os-21-1255-2025, 2025
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Marine heatwaves are of growing concern around the world. We use a state-of-the-art ensemble of downscaled climate models to project how often heatwaves will occur in the future across northwestern Europe under a high-emission scenario. The projections show that, without emission reductions, heatwaves will occur more than half of the time in the future. We show that the seafloor is expected to experience much more frequent heatwaves than the sea surface in the future.
Melissa Wood, Ivan D. Haigh, Quan Quan Le, Hung Nghia Nguyen, Hoang Ba Tran, Stephen E. Darby, Robert Marsh, Nikolaos Skliris, and Joël J.-M. Hirschi
Nat. Hazards Earth Syst. Sci., 24, 3627–3649, https://doi.org/10.5194/nhess-24-3627-2024, https://doi.org/10.5194/nhess-24-3627-2024, 2024
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We look at how compound flooding from the combination of river flooding and storm tides (storm surge and astronomical tide) may be changing over time due to climate change, with a case study of the Mekong River delta. We found that future compound flooding has the potential to flood the region more extensively and be longer lasting than compound floods today. This is useful to know because it means managers of deltas such as the Mekong can assess options for improving existing flood defences.
Giovanni Galli, Sarah Wakelin, James Harle, Jason Holt, and Yuri Artioli
Biogeosciences, 21, 2143–2158, https://doi.org/10.5194/bg-21-2143-2024, https://doi.org/10.5194/bg-21-2143-2024, 2024
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This work shows that, under a high-emission scenario, oxygen concentration in deep water of parts of the North Sea and Celtic Sea can become critically low (hypoxia) towards the end of this century. The extent and frequency of hypoxia depends on the intensity of climate change projected by different climate models. This is the result of a complex combination of factors like warming, increase in stratification, changes in the currents and changes in biological processes.
Jeff Polton, James Harle, Jason Holt, Anna Katavouta, Dale Partridge, Jenny Jardine, Sarah Wakelin, Julia Rulent, Anthony Wise, Katherine Hutchinson, David Byrne, Diego Bruciaferri, Enda O'Dea, Michela De Dominicis, Pierre Mathiot, Andrew Coward, Andrew Yool, Julien Palmiéri, Gennadi Lessin, Claudia Gabriela Mayorga-Adame, Valérie Le Guennec, Alex Arnold, and Clément Rousset
Geosci. Model Dev., 16, 1481–1510, https://doi.org/10.5194/gmd-16-1481-2023, https://doi.org/10.5194/gmd-16-1481-2023, 2023
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The aim is to increase the capacity of the modelling community to respond to societally important questions that require ocean modelling. The concept of reproducibility for regional ocean modelling is developed: advocating methods for reproducible workflows and standardised methods of assessment. Then, targeting the NEMO framework, we give practical advice and worked examples, highlighting key considerations that will the expedite development cycle and upskill the user community.
Paul R. Halloran, Jennifer K. McWhorter, Beatriz Arellano Nava, Robert Marsh, and William Skirving
Geosci. Model Dev., 14, 6177–6195, https://doi.org/10.5194/gmd-14-6177-2021, https://doi.org/10.5194/gmd-14-6177-2021, 2021
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This paper describes the latest version of a simple model for simulating coastal oceanography in response to changes in weather and climate. The latest revision of this model makes scientific improvements but focuses on improvements that allow the model to be run simply at large scales and for long periods of time to explore the implications of (for example) future climate change along large areas of coastline.
Gandy Maria Rosales Quintana, Robert Marsh, and Luis Alfredo Icochea Salas
Ocean Sci., 17, 1385–1402, https://doi.org/10.5194/os-17-1385-2021, https://doi.org/10.5194/os-17-1385-2021, 2021
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The Equatorial Undercurrent (EUC) is a key influence on upwelling of nutrient-rich waters associated ecosystems off Peru. To quantify this influence, we backtrack upwelling waters in a computer model of ocean currents, annually, over 1989–2007. The EUC influence varies from year to year, dominating in warm El Niño years, when the EUC extends much closer to the Peruvian coast. In other years, more
localupwelling is associated with coastal winds, coincident with major key population shifts.
Emma L. Worthington, Ben I. Moat, David A. Smeed, Jennifer V. Mecking, Robert Marsh, and Gerard D. McCarthy
Ocean Sci., 17, 285–299, https://doi.org/10.5194/os-17-285-2021, https://doi.org/10.5194/os-17-285-2021, 2021
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The RAPID array has observed the Atlantic meridional overturning circulation (AMOC) since 2004, but the AMOC was directly calculated only five times from 1957–2004. Here we create a statistical regression model from RAPID data, relating AMOC changes to density changes within the different water masses at 26° N, and apply it to historical hydrographic data. The resulting 1981–2016 record shows that the AMOC from 2008–2012 was its weakest since the mid-1980s, but it shows no overall decline.
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Short summary
The European Slope Current (SC) is a northward-flowing current running parallel to the UK coastline. It is forced by changes in the density gradient of the wider North Atlantic Ocean. As the North Atlantic has warmed since the late 1990s, these gradients have changed strength and moved, reducing the volume and speed of water feeding into the SC. The SC flows into the North Sea, where changes in the species distribution of some plankton and fish have been seen due to the warming inputs.
The European Slope Current (SC) is a northward-flowing current running parallel to the UK...