Articles | Volume 11, issue 3 
            
                
                    
            
            
            https://doi.org/10.5194/os-11-343-2015
                    © Author(s) 2015. This work is distributed under 
the Creative Commons Attribution 3.0 License.
                the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/os-11-343-2015
                    © Author(s) 2015. This work is distributed under 
the Creative Commons Attribution 3.0 License.
                the Creative Commons Attribution 3.0 License.
Deep drivers of mesoscale circulation in the central Rockall Trough
T. J. Sherwin
CORRESPONDING AUTHOR
                                            
                                    
                                            Scottish Association for Marine Science, Scottish Marine Institute, Oban PA37 1QA, UK
                                        
                                    D. Aleynik
                                            Scottish Association for Marine Science, Scottish Marine Institute, Oban PA37 1QA, UK
                                        
                                    E. Dumont
                                            Scottish Association for Marine Science, Scottish Marine Institute, Oban PA37 1QA, UK
                                        
                                    M. E. Inall
                                            Scottish Association for Marine Science, Scottish Marine Institute, Oban PA37 1QA, UK
                                        
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B. Berx, B. Hansen, S. Østerhus, K. M. Larsen, T. Sherwin, and K. Jochumsen
                                    Ocean Sci., 9, 639–654, https://doi.org/10.5194/os-9-639-2013, https://doi.org/10.5194/os-9-639-2013, 2013
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                                    This preprint is open for discussion and under review for Ocean Science (OS). 
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                                                The Rockall Trough carries key ocean currents that affect Europe’s climate and seas. Researchers combined data from underwater sensors and robotic gliders to track water, heat, and freshwater flow from 2014 to 2022. They created a new method to merge this data, producing the first long-term record of one important current. This improves ocean monitoring and helps us better understand climate-related changes.
                                            
                                            
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                                                Glacial fjords connect ice sheets to the ocean, controlling heat delivery to glaciers, which impacts ice sheet melt, and freshwater discharge to the ocean, affecting ocean circulation. However, their dynamics are not captured in large-scale climate models. We designed a simplified, computationally efficient model – FjordRPM – which accurately captures key fjord processes. It has direct applications for improving projections of ice melt, ocean circulation and sea-level rise.
                                            
                                            
                                        Kristin Burmeister, Franziska U. Schwarzkopf, Willi Rath, Arne Biastoch, Peter Brandt, Joke F. Lübbecke, and Mark Inall
                                    Ocean Sci., 20, 307–339, https://doi.org/10.5194/os-20-307-2024, https://doi.org/10.5194/os-20-307-2024, 2024
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                                                We apply two different forcing products to a high-resolution ocean model to investigate their impact on the simulated upper-current field in the tropical Atlantic. Where possible, we compare the simulated results to long-term observations. We find large discrepancies between the two simulations regarding the wind and current fields. We propose that long-term observations, once they have reached a critical length, need to be used to test the quality of wind-driven simulations.
                                            
                                            
                                        Sam C. Jones, Neil J. Fraser, Stuart A. Cunningham, Alan D. Fox, and Mark E. Inall
                                    Ocean Sci., 19, 169–192, https://doi.org/10.5194/os-19-169-2023, https://doi.org/10.5194/os-19-169-2023, 2023
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                                                Warm water is transported from the tropical Atlantic towards western Europe and the Arctic.  It loses heat to the atmosphere on the way, which strongly influences the climate. We construct a dataset encircling the North Atlantic basin north of 47° N. We calculate how and where heat enters and leaves the basin and how much cooling must happen in the interior. We find that cooling in the north-eastern Atlantic is a crucial step in controlling the conversion of water to higher densities.
                                            
                                            
                                        Benjamin R. Loveday, Timothy Smyth, Anıl Akpinar, Tom Hull, Mark E. Inall, Jan Kaiser, Bastien Y. Queste, Matt Tobermann, Charlotte A. J. Williams, and Matthew R. Palmer
                                    Earth Syst. Sci. Data, 14, 3997–4016, https://doi.org/10.5194/essd-14-3997-2022, https://doi.org/10.5194/essd-14-3997-2022, 2022
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                                                Using a new approach to combine autonomous underwater glider data and satellite Earth observations, we have generated a 19-month time series of North Sea net primary productivity – the rate at which phytoplankton absorbs carbon dioxide minus that lost through respiration. This time series, which spans 13 gliders, allows for new investigations into small-scale, high-frequency variability in the biogeochemical processes that underpin the carbon cycle and coastal marine ecosystems in shelf seas.
                                            
                                            
                                        Sam Jones, Mark Inall, Marie Porter, Jennifer A. Graham, and Finlo Cottier
                                    Ocean Sci., 16, 389–403, https://doi.org/10.5194/os-16-389-2020, https://doi.org/10.5194/os-16-389-2020, 2020
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                                                The ocean is an important source of nutrients and organisms to coastal waters, but it is not clear what controls current flow between the deep ocean and the coast. We contrasted ocean flow pathways and coastal water properties between summer 2013 and a series of intense storms in December 2013. Further, we assessed the likelihood of storms occurring over the North Atlantic during each winter. We found that local weather patterns exert a strong influence on coastal water properties and origins.
                                            
                                            
                                        Robert Marsh, Ivan D. Haigh, Stuart A. Cunningham, Mark E. Inall, Marie Porter, and Ben I. Moat
                                    Ocean Sci., 13, 315–335, https://doi.org/10.5194/os-13-315-2017, https://doi.org/10.5194/os-13-315-2017, 2017
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                                                To the west of Britain and Ireland, a strong ocean current follows the steep slope that separates the deep Atlantic and the continental shelf. This “Slope Current” exerts an Atlantic influence on the North Sea and its ecosystems. Using a combination of computer modelling and archived data, we find that the Slope Current weakened over 1988–2007, reducing Atlantic influence on the North Sea, due to a combination of warming of the subpolar North Atlantic and weakening winds to the west of Scotland.
                                            
                                            
                                        J. Friedrich, F. Janssen, D. Aleynik, H. W. Bange, N. Boltacheva, M. N. Çagatay, A. W. Dale, G. Etiope, Z. Erdem, M. Geraga, A. Gilli, M. T. Gomoiu, P. O. J. Hall, D. Hansson, Y. He, M. Holtappels, M. K. Kirf, M. Kononets, S. Konovalov, A. Lichtschlag, D. M. Livingstone, G. Marinaro, S. Mazlumyan, S. Naeher, R. P. North, G. Papatheodorou, O. Pfannkuche, R. Prien, G. Rehder, C. J. Schubert, T. Soltwedel, S. Sommer, H. Stahl, E. V. Stanev, A. Teaca, A. Tengberg, C. Waldmann, B. Wehrli, and F. Wenzhöfer
                                    Biogeosciences, 11, 1215–1259, https://doi.org/10.5194/bg-11-1215-2014, https://doi.org/10.5194/bg-11-1215-2014, 2014
                            B. Berx, B. Hansen, S. Østerhus, K. M. Larsen, T. Sherwin, and K. Jochumsen
                                    Ocean Sci., 9, 639–654, https://doi.org/10.5194/os-9-639-2013, https://doi.org/10.5194/os-9-639-2013, 2013
                            Related subject area
            Approach: In situ Observations | Depth range: All Depths | Geographical range: Deep Seas: North Atlantic | Phenomena: Current Field
            
                    
                        
                            
                            
                                     
                                3D reconstruction of ocean velocity from high-frequency radar and acoustic Doppler current profiler: a model-based assessment study
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Mass, nutrients and dissolved organic carbon (DOC) lateral transports off northwest Africa during fall 2002 and spring 2003
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Surface predictor of overturning circulation and heat content change in the subpolar North Atlantic
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Arctic Mediterranean exchanges: a consistent volume budget and trends in transports from two decades of observations
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Atlantic Meridional Overturning Circulation at 14.5° N in 1989 and 2013 and 24.5° N in 1992 and 2015: volume, heat, and freshwater transports
                                
                                        
                                            
                                    
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Atlantic water flow through the Faroese Channels
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                A stable Faroe Bank Channel overflow 1995–2015
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Compensation between meridional flow components of the Atlantic MOC at 26° N
                                
                                        
                                            
                                    
                            
                            
                            
                        
                    
                    
                        
                            
                            
                                     
                                Impact of a 30% reduction in Atlantic meridional overturning during 2009–2010
                                
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                Atlantic transport variability at 25° N in six hydrographic sections
                                
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                On the seasonal cycles and variability of Florida Straits, Ekman and Sverdrup transports at 26° N in the Atlantic Ocean
                                
                            
                            
                        
                    
                    
                        
                            
                            
                            
                                     
                                The contribution of eastern-boundary density variations to the Atlantic meridional overturning circulation at 26.5° N
                                
                            
                            
                        
                    
                    
            
        
        Ivan Manso-Narvarte, Erick Fredj, Gabriel Jordà, Maristella Berta, Annalisa Griffa, Ainhoa Caballero, and Anna Rubio
                                    Ocean Sci., 16, 575–591, https://doi.org/10.5194/os-16-575-2020, https://doi.org/10.5194/os-16-575-2020, 2020
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                                                Our main aim is to study the feasibility of reconstructing oceanic currents by extending the data obtained from coastal multiplatform observatories to nearby areas in 3D in the SE Bay of Biscay. To that end, two different data-reconstruction methods with different approaches were tested, providing satisfactory results. This work is a first step towards the real applicability of these methods in this study area, and it shows the capabilities of the methods for a wide range of applications.
                                            
                                            
                                        Nadia Burgoa, Francisco Machín, Ángeles Marrero-Díaz, Ángel Rodríguez-Santana, Antonio Martínez-Marrero, Javier Arístegui, and Carlos Manuel Duarte
                                    Ocean Sci., 16, 483–511, https://doi.org/10.5194/os-16-483-2020, https://doi.org/10.5194/os-16-483-2020, 2020
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                                                The main objective of the study is to analyze the export of carbon to the open ocean from the rich waters of the upwelling system of North Africa. South of the Canary Islands, permanent upwelling interacts with other physical processes impacting the main biogeochemical processes. Taking advantage of data from two cruises combined with the outputs of models, important conclusions from the differences observed between seasons are obtained, largely related to changes in the CVFZ in this area.
                                            
                                            
                                        Damien G. Desbruyères, Herlé Mercier, Guillaume Maze, and Nathalie Daniault
                                    Ocean Sci., 15, 809–817, https://doi.org/10.5194/os-15-809-2019, https://doi.org/10.5194/os-15-809-2019, 2019
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                                                In the North Atlantic, ocean currents transport warm waters northward in the upper water column, and cold waters southwards at depth. This circulation is here reconstructed from surface data and thermodynamics theory. Its driving role in recent temperature changes (1993–2017) in the North Atlantic is evidenced, and predictions of near-future variability (5 years) are provided and discussed.
                                            
                                            
                                        Svein Østerhus, Rebecca Woodgate, Héðinn Valdimarsson, Bill Turrell, Laura de Steur, Detlef Quadfasel, Steffen M. Olsen, Martin Moritz, Craig M. Lee, Karin Margretha H. Larsen, Steingrímur Jónsson, Clare Johnson, Kerstin Jochumsen, Bogi Hansen, Beth Curry, Stuart Cunningham, and Barbara Berx
                                    Ocean Sci., 15, 379–399, https://doi.org/10.5194/os-15-379-2019, https://doi.org/10.5194/os-15-379-2019, 2019
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                                                Two decades of observations of the Arctic Mediterranean (AM) exchanges show that the exchanges have been stable in terms of volume transport during a period when many other components of the global climate system have changed. The total AM import is found to be 9.1 Sv and has a seasonal variation in amplitude close to 1 Sv, and maximum import in October. Roughly one-third of the imported water leaves the AM as surface outflow.
                                            
                                            
                                        Yao Fu, Johannes Karstensen, and Peter Brandt
                                    Ocean Sci., 14, 589–616, https://doi.org/10.5194/os-14-589-2018, https://doi.org/10.5194/os-14-589-2018, 2018
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                                                Hydrographic analysis in the Atlantic along 14.5° N and 24.5° N shows that between the periods of 1989/92 and 2013/15, the Antarctic Intermediate Water became warmer and saltier at 14.5° N, and that the Antarctic Bottom Water became lighter at both latitudes. By applying a box inverse model, the Atlantic Meridional Overturning Circulation (AMOC) was determined. Comparison among the inverse solution, GECCO2, RAPID, and MOVE shows that the AMOC has not significantly changed in the past 20 years.
                                            
                                            
                                        Bogi Hansen, Turið Poulsen, Karin Margretha Húsgarð Larsen, Hjálmar Hátún, Svein Østerhus, Elin Darelius, Barbara Berx, Detlef Quadfasel, and Kerstin Jochumsen
                                    Ocean Sci., 13, 873–888, https://doi.org/10.5194/os-13-873-2017, https://doi.org/10.5194/os-13-873-2017, 2017
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                                                On its way towards the Arctic, an important branch of warm Atlantic water passes through the Faroese Channels, but, in spite of more than a century of investigations, the detailed flow pattern through this channel system has not been resolved. This has strong implications for estimates of oceanic heat transport towards the Arctic. Here, we combine observations from various sources, which together paint a coherent picture of the Atlantic water flow and heat transport through this channel system.
                                            
                                            
                                        Bogi Hansen, Karin Margretha Húsgarð Larsen, Hjálmar Hátún, and Svein Østerhus
                                    Ocean Sci., 12, 1205–1220, https://doi.org/10.5194/os-12-1205-2016, https://doi.org/10.5194/os-12-1205-2016, 2016
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                                                The Faroe Bank Channel is one of the main passages for the flow of cold dense water from the Arctic into the depths of the world ocean where it feeds the deep branch of the AMOC. Based on in situ measurements, we show that the volume transport of this flow has been stable from 1995 to 2015. The water has warmed, but salinity increase has maintained its high density. Thus, this branch of the AMOC did not weaken during the last 2 decades, but increased its heat transport into the deep ocean.
                                            
                                            
                                        E. Frajka-Williams, C. S. Meinen, W. E. Johns, D. A. Smeed, A. Duchez, A. J. Lawrence, D. A. Cuthbertson, G. D. McCarthy, H. L. Bryden, M. O. Baringer, B. I. Moat, and D. Rayner
                                    Ocean Sci., 12, 481–493, https://doi.org/10.5194/os-12-481-2016, https://doi.org/10.5194/os-12-481-2016, 2016
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                                                The ocean meridional overturning circulation (MOC) is predicted by climate models to slow down in this century, resulting in reduced transport of heat northward to mid-latitudes.  At 26° N, the Atlantic MOC has been measured continuously for the past decade (2004–2014).  In this paper, we discuss the 10-year record of variability, identify the origins of the continued weakening of the circulation, and discuss high-frequency (subannual) compensation between transport components.
                                            
                                            
                                        H. L. Bryden, B. A. King, G. D. McCarthy, and E. L. McDonagh
                                    Ocean Sci., 10, 683–691, https://doi.org/10.5194/os-10-683-2014, https://doi.org/10.5194/os-10-683-2014, 2014
                            C. P. Atkinson, H. L. Bryden, S. A. Cunningham, and B. A. King
                                    Ocean Sci., 8, 497–523, https://doi.org/10.5194/os-8-497-2012, https://doi.org/10.5194/os-8-497-2012, 2012
                            C. P. Atkinson, H. L. Bryden, J. J-M. Hirschi, and T. Kanzow
                                    Ocean Sci., 6, 837–859, https://doi.org/10.5194/os-6-837-2010, https://doi.org/10.5194/os-6-837-2010, 2010
                            M. P. Chidichimo, T. Kanzow, S. A. Cunningham, W. E. Johns, and J. Marotzke
                                    Ocean Sci., 6, 475–490, https://doi.org/10.5194/os-6-475-2010, https://doi.org/10.5194/os-6-475-2010, 2010
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                Short summary
            The Rockall Trough feeds warm salty water to Polar regions and the European Shelf. Detailed observations from an underwater glider show that a) the meandering surface current field in the central trough is driven by deep eddies; b) chance circulations deflect the eastern slope current and warm the western side; c) and altimeter observations omit the mean flow in the narrow slope current. There are wider implications for satellite altimeter observations, ocean monitoring and ocean model results.
            The Rockall Trough feeds warm salty water to Polar regions and the European Shelf. Detailed...