Articles | Volume 13, issue 6
https://doi.org/10.5194/os-13-873-2017
© Author(s) 2017. 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-13-873-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
13 Nov 2017
Research article |
| 13 Nov 2017
Atlantic water flow through the Faroese Channels
Bogi Hansen
CORRESPONDING AUTHOR
Faroe Marine Research Institute, P.O. Box 3051, 110 Tórshavn, Faroe Islands
Turið Poulsen
Faroe Marine Research Institute, P.O. Box 3051, 110 Tórshavn, Faroe Islands
Karin Margretha Húsgarð Larsen
Faroe Marine Research Institute, P.O. Box 3051, 110 Tórshavn, Faroe Islands
Hjálmar Hátún
Faroe Marine Research Institute, P.O. Box 3051, 110 Tórshavn, Faroe Islands
Svein Østerhus
Uni Research Climate and the Bjerknes Centre for Climate Research, Nygårdsgata 112, 5008 Bergen, Norway
Elin Darelius
Geophysical Institute, University of Bergen and the Bjerknes Centre for Climate Research, Allég. 70, 5007 Bergen, Norway
Barbara Berx
Marine Scotland Science, 375 Victoria Road, Aberdeen, AB11 9DB, UK
Detlef Quadfasel
Institut für Meereskunde, Universität Hamburg, Bundesstrasse 53, 20146 Hamburg, Germany
Kerstin Jochumsen
Institut für Meereskunde, Universität Hamburg, Bundesstrasse 53, 20146 Hamburg, Germany
Related authors
Bogi Hansen, Karin M. H. Larsen, Hjálmar Hátún, Steffen M. Olsen, Andrea M. U. Gierisch, Svein Østerhus, and Sólveig R. Ólafsdóttir
Ocean Sci., 19, 1225–1252, https://doi.org/10.5194/os-19-1225-2023, https://doi.org/10.5194/os-19-1225-2023, 2023
Short summary
Short summary
Based on in situ observations combined with sea level anomaly (SLA) data from satellite altimetry, volume as well as heat (relative to 0 °C) transport of the Iceland–Faroe warm-water inflow towards the Arctic (IF inflow) increased from 1993 to 2021. The reprocessed SLA data released in December 2021 represent observed variations accurately. The IF inflow crosses the Iceland–Faroe Ridge in two branches, with retroflection in between. The associated coupling to overflow reduces predictability.
Sissal Vágsheyg Erenbjerg, Jon Albretsen, Knud Simonsen, Erna Lava Olsen, Eigil Kaas, and Bogi Hansen
Ocean Sci., 17, 1639–1655, https://doi.org/10.5194/os-17-1639-2021, https://doi.org/10.5194/os-17-1639-2021, 2021
Short summary
Short summary
Here, we describe a strait that has narrow and shallow sills in both ends and is close to an amphidromic region. This generates tidally driven flows into and out of the strait, but with very different exchange rates across the entrances in both ends so that it behaves like a mixture between a strait and a fjord. Using a numerical model, we find a fortnightly signal in the net transport through the strait, generated by long-period tides. Our findings are verified by observations.
Bogi Hansen, Karin Margretha Húsgarð Larsen, Hjálmar Hátún, Steingrímur Jónsson, Sólveig Rósa Ólafsdóttir, Andreas Macrander, William Johns, N. Penny Holliday, and Steffen Malskær Olsen
Ocean Sci. Discuss., https://doi.org/10.5194/os-2021-14, https://doi.org/10.5194/os-2021-14, 2021
Preprint withdrawn
Short summary
Short summary
Compared to other freshwater sources, runoff from Iceland is small and usually flows into the Nordic Seas. Under certain wind conditions, it can, however, flow into the Iceland Basin and this occurred after 2014, when this region had already freshened from other causes. This explains why the surface freshening in this area became so extreme. The local and shallow character of this runoff allows it to have a disproportionate effect on vertical mixing, winter convection, and biological production.
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
Short summary
Short summary
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.
Bogi Hansen, Karin Margretha Húsgarð Larsen, Steffen Malskær Olsen, Detlef Quadfasel, Kerstin Jochumsen, and Svein Østerhus
Ocean Sci., 14, 871–885, https://doi.org/10.5194/os-14-871-2018, https://doi.org/10.5194/os-14-871-2018, 2018
Short summary
Short summary
The Western Valley is one of the passages across the Iceland–Scotland Ridge through which a strong overflow of cold, dense water has been thought to feed the deep limb of the Atlantic Meridional Overturning Circulation (AMOC), but its strength has not been known. Based on a field experiment with instruments moored across the valley, we show that this overflow branch is much weaker than previously thought and that this is because it is suppressed by the warm countercurrent in the upper layers.
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
Short summary
Short summary
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.
S. M. Olsen, B. Hansen, S. Østerhus, D. Quadfasel, and H. Valdimarsson
Ocean Sci., 12, 545–560, https://doi.org/10.5194/os-12-545-2016, https://doi.org/10.5194/os-12-545-2016, 2016
Short summary
Short summary
About half of the warm Atlantic water that enters the Norwegian Sea flows between Iceland and the Faroes. Here it crosses the Iceland-Faroe Ridge and dynamically interacts with the cold, dense and deep return flow across the ridge. This flow is not resolved in climate models and the lack of interaction prevents realistic heat anomaly propagation towards the Arctic.
B. Hansen, K. M. H. Larsen, H. Hátún, R. Kristiansen, E. Mortensen, and S. Østerhus
Ocean Sci., 11, 743–757, https://doi.org/10.5194/os-11-743-2015, https://doi.org/10.5194/os-11-743-2015, 2015
Short summary
Short summary
The Faroe Current is the main ocean current transporting warm Atlantic water into the Arctic region and an important transporter of heat towards the Arctic. This study documents observed transport variations over two decades, from 1993 to 2013. It shows that the volume transport of Atlantic water in this current increased by 9% over the period, whereas the heat transport increased by 18%. This increase will have contributed to the observed warming and sea ice decline in the Arctic.
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
Julius Lauber, Tore Hattermann, Laura de Steur, Elin Darelius, and Agneta Fransson
EGUsphere, https://doi.org/10.5194/egusphere-2024-904, https://doi.org/10.5194/egusphere-2024-904, 2024
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Recent studies have highlighted the potential vulnerability of the East Antarctic Ice Sheet to atmospheric and oceanic changes. We present new insights from observations from three oceanic moorings below Fimbulisen Ice Shelf from 2009 to 2021. We find that relatively warm water masses reach below the ice shelf both close to the surface and at depth with implications for the basal melting of Fimbulisen.
Michael Mayer, Takamasa Tsubouchi, Susanna Winkelbauer, Karin Margretha H. Larsen, Barbara Berx, Andreas Macrander, Doroteaciro Iovino, Steingrímur Jónsson, and Richard Renshaw
State Planet, 1-osr7, 14, https://doi.org/10.5194/sp-1-osr7-14-2023, https://doi.org/10.5194/sp-1-osr7-14-2023, 2023
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This paper compares oceanic fluxes across the Greenland–Scotland Ridge (GSR) from ocean reanalyses to largely independent observational data. Reanalyses tend to underestimate the inflow of warm waters of subtropical Atlantic origin and hence oceanic heat transport across the GSR. Investigation of a strong negative heat transport anomaly around 2018 highlights the interplay of variability on different timescales and the need for long-term monitoring of the GSR to detect forced climate signals.
Bogi Hansen, Karin M. H. Larsen, Hjálmar Hátún, Steffen M. Olsen, Andrea M. U. Gierisch, Svein Østerhus, and Sólveig R. Ólafsdóttir
Ocean Sci., 19, 1225–1252, https://doi.org/10.5194/os-19-1225-2023, https://doi.org/10.5194/os-19-1225-2023, 2023
Short summary
Short summary
Based on in situ observations combined with sea level anomaly (SLA) data from satellite altimetry, volume as well as heat (relative to 0 °C) transport of the Iceland–Faroe warm-water inflow towards the Arctic (IF inflow) increased from 1993 to 2021. The reprocessed SLA data released in December 2021 represent observed variations accurately. The IF inflow crosses the Iceland–Faroe Ridge in two branches, with retroflection in between. The associated coupling to overflow reduces predictability.
Elin Darelius, Vår Dundas, Markus Janout, and Sandra Tippenhauer
Ocean Sci., 19, 671–683, https://doi.org/10.5194/os-19-671-2023, https://doi.org/10.5194/os-19-671-2023, 2023
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Antarctica's ice shelves are melting from below as ocean currents bring warm water into the ice shelf cavities. The melt rates of the large Filchner–Ronne Ice Shelf in the southern Weddell Sea are currently low, as the water in the cavity is cold. Here, we present data from a scientific cruise to the region in 2021 and show that the warmest water at the upper part of the continental slope is now about 0.1°C warmer than in previous observations, while the surface water is fresher than before.
Turið Poulsen, Bárður A. Niclasen, Gregor Giebel, and Hans Georg Beyer
Wind Energ. Sci., 7, 2335–2350, https://doi.org/10.5194/wes-7-2335-2022, https://doi.org/10.5194/wes-7-2335-2022, 2022
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Wind power is cheap and environmentally friendly, but it has a disadvantage: it is a variable power source. Because wind is not blowing everywhere simultaneously, optimal placement of wind farms can reduce the fluctuations.
This is explored for a small isolated area. Combining wind farms reduces wind power fluctuations for timescales up to 1–2 d. By optimally placing four wind farms, the hourly fluctuations are reduced by 15 %. These wind farms are located distant from each other.
Vår Dundas, Elin Darelius, Kjersti Daae, Nadine Steiger, Yoshihiro Nakayama, and Tae-Wan Kim
Ocean Sci., 18, 1339–1359, https://doi.org/10.5194/os-18-1339-2022, https://doi.org/10.5194/os-18-1339-2022, 2022
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Ice shelves in the Amundsen Sea are thinning rapidly as ocean currents bring warm water into cavities beneath the floating ice. We use 2-year-long mooring records and 16-year-long model simulations to describe the hydrography and circulation near the ice front between Siple and Carney Islands. We find that temperatures here are lower than at neighboring ice fronts and that the transport of heat toward the cavity is governed by wind stress over the Amundsen Sea continental shelf.
Sissal Vágsheyg Erenbjerg, Jon Albretsen, Knud Simonsen, Erna Lava Olsen, Eigil Kaas, and Bogi Hansen
Ocean Sci., 17, 1639–1655, https://doi.org/10.5194/os-17-1639-2021, https://doi.org/10.5194/os-17-1639-2021, 2021
Short summary
Short summary
Here, we describe a strait that has narrow and shallow sills in both ends and is close to an amphidromic region. This generates tidally driven flows into and out of the strait, but with very different exchange rates across the entrances in both ends so that it behaves like a mixture between a strait and a fjord. Using a numerical model, we find a fortnightly signal in the net transport through the strait, generated by long-period tides. Our findings are verified by observations.
Bogi Hansen, Karin Margretha Húsgarð Larsen, Hjálmar Hátún, Steingrímur Jónsson, Sólveig Rósa Ólafsdóttir, Andreas Macrander, William Johns, N. Penny Holliday, and Steffen Malskær Olsen
Ocean Sci. Discuss., https://doi.org/10.5194/os-2021-14, https://doi.org/10.5194/os-2021-14, 2021
Preprint withdrawn
Short summary
Short summary
Compared to other freshwater sources, runoff from Iceland is small and usually flows into the Nordic Seas. Under certain wind conditions, it can, however, flow into the Iceland Basin and this occurred after 2014, when this region had already freshened from other causes. This explains why the surface freshening in this area became so extreme. The local and shallow character of this runoff allows it to have a disproportionate effect on vertical mixing, winter convection, and biological production.
Rob A. Hall, Barbara Berx, and Gillian M. Damerell
Ocean Sci., 15, 1439–1453, https://doi.org/10.5194/os-15-1439-2019, https://doi.org/10.5194/os-15-1439-2019, 2019
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Internal tides are subsurface waves generated by tidal flows over ocean ridges. When they break they create turbulence that drives an upward flux of nutrients from the deep ocean to the nutrient-poor photic zone. Measuring internal tides is problematic because oceanographic moorings are often
fished-outby commercial trawlers. We show that autonomous ocean gliders and acoustic Doppler current profilers can be used together to accurately measure the amount of energy carried by internal tides.
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
Short summary
Short summary
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.
Bogi Hansen, Karin Margretha Húsgarð Larsen, Steffen Malskær Olsen, Detlef Quadfasel, Kerstin Jochumsen, and Svein Østerhus
Ocean Sci., 14, 871–885, https://doi.org/10.5194/os-14-871-2018, https://doi.org/10.5194/os-14-871-2018, 2018
Short summary
Short summary
The Western Valley is one of the passages across the Iceland–Scotland Ridge through which a strong overflow of cold, dense water has been thought to feed the deep limb of the Atlantic Meridional Overturning Circulation (AMOC), but its strength has not been known. Based on a field experiment with instruments moored across the valley, we show that this overflow branch is much weaker than previously thought and that this is because it is suppressed by the warm countercurrent in the upper layers.
Peter M. F. Sheehan, Barbara Berx, Alejandro Gallego, Rob A. Hall, Karen J. Heywood, Sarah L. Hughes, and Bastien Y. Queste
Ocean Sci., 14, 225–236, https://doi.org/10.5194/os-14-225-2018, https://doi.org/10.5194/os-14-225-2018, 2018
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We calculate tidal velocities using observations of ocean currents collected by an underwater glider. We use these velocities to investigate the location of sharp boundaries between water masses in shallow seas. Narrow currents along these boundaries are important transport pathways around shallow seas for pollutants and organisms. Tides are an important control on boundary location in summer, but seawater salt concentration can also influence boundary location, especially in winter.
Barbara Berx and Mark R. Payne
Earth Syst. Sci. Data, 9, 259–266, https://doi.org/10.5194/essd-9-259-2017, https://doi.org/10.5194/essd-9-259-2017, 2017
Short summary
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We present a freely available Sub-Polar Gyre Index, consistent with previous calculation methods, for the use of the wider community in their analyses. The paper describes the methodology and interpretation and includes some sensitivity analysis.
Amelie Driemel, Eberhard Fahrbach, Gerd Rohardt, Agnieszka Beszczynska-Möller, Antje Boetius, Gereon Budéus, Boris Cisewski, Ralph Engbrodt, Steffen Gauger, Walter Geibert, Patrizia Geprägs, Dieter Gerdes, Rainer Gersonde, Arnold L. Gordon, Hannes Grobe, Hartmut H. Hellmer, Enrique Isla, Stanley S. Jacobs, Markus Janout, Wilfried Jokat, Michael Klages, Gerhard Kuhn, Jens Meincke, Sven Ober, Svein Østerhus, Ray G. Peterson, Benjamin Rabe, Bert Rudels, Ursula Schauer, Michael Schröder, Stefanie Schumacher, Rainer Sieger, Jüri Sildam, Thomas Soltwedel, Elena Stangeew, Manfred Stein, Volker H Strass, Jörn Thiede, Sandra Tippenhauer, Cornelis Veth, Wilken-Jon von Appen, Marie-France Weirig, Andreas Wisotzki, Dieter A. Wolf-Gladrow, and Torsten Kanzow
Earth Syst. Sci. Data, 9, 211–220, https://doi.org/10.5194/essd-9-211-2017, https://doi.org/10.5194/essd-9-211-2017, 2017
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Our oceans are always in motion – huge water masses are circulated by winds and by global seawater density gradients resulting from different water temperatures and salinities. Measuring temperature and salinity of the world's oceans is crucial e.g. to understand our climate. Since 1983, the research icebreaker Polarstern has been the basis of numerous water profile measurements in the Arctic and the Antarctic. We report on a unique collection of 33 years of polar salinity and temperature data.
Stefanie Semper and Elin Darelius
Ocean Sci., 13, 77–93, https://doi.org/10.5194/os-13-77-2017, https://doi.org/10.5194/os-13-77-2017, 2017
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Velocity measurements from moorings at the shelf break in the southern Weddell Sea reveal strong diurnal tidal currents, which are enhanced by ca. 50 % in austral summer compared to winter. A numerical code describing coastal trapped waves (CTWs) is used to explore the effect of changing stratification and circulation on wave properties. It is found that near-resonance between CTWs and diurnal tides during austral summer can explain the observed enhancement of diurnal tidal currents.
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
Short summary
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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.
S. M. Olsen, B. Hansen, S. Østerhus, D. Quadfasel, and H. Valdimarsson
Ocean Sci., 12, 545–560, https://doi.org/10.5194/os-12-545-2016, https://doi.org/10.5194/os-12-545-2016, 2016
Short summary
Short summary
About half of the warm Atlantic water that enters the Norwegian Sea flows between Iceland and the Faroes. Here it crosses the Iceland-Faroe Ridge and dynamically interacts with the cold, dense and deep return flow across the ridge. This flow is not resolved in climate models and the lack of interaction prevents realistic heat anomaly propagation towards the Arctic.
Jenny E. Ullgren, Elin Darelius, and Ilker Fer
Ocean Sci., 12, 451–470, https://doi.org/10.5194/os-12-451-2016, https://doi.org/10.5194/os-12-451-2016, 2016
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One-year long moored measurements of currents and hydrographic properties in the overflow region of the Faroe Bank Channel have provided a more accurate observational-based estimate of the volume transport, entrainment, and eddy diffusivities associated with the overflow plume. The data set resolves the temporal variability and covers the entire lateral and vertical extent of the plume.
E. Darelius, I. Fer, T. Rasmussen, C. Guo, and K. M. H. Larsen
Ocean Sci., 11, 855–871, https://doi.org/10.5194/os-11-855-2015, https://doi.org/10.5194/os-11-855-2015, 2015
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Quasi-regular eddies are known to be generated in the outflow of dense water through the Faroe Bank Channel. One year long mooring records from the plume region show that (1) the energy associated with the eddies varies by a factor of 10 throughout the year and (2) the frequency of the eddies shifts between 3 and 6 days and is related to the strength of the outflow. Similar variability is shown by a high-resolution regional model and the observations agree with theory on baroclinic instability.
B. Hansen, K. M. H. Larsen, H. Hátún, R. Kristiansen, E. Mortensen, and S. Østerhus
Ocean Sci., 11, 743–757, https://doi.org/10.5194/os-11-743-2015, https://doi.org/10.5194/os-11-743-2015, 2015
Short summary
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The Faroe Current is the main ocean current transporting warm Atlantic water into the Arctic region and an important transporter of heat towards the Arctic. This study documents observed transport variations over two decades, from 1993 to 2013. It shows that the volume transport of Atlantic water in this current increased by 9% over the period, whereas the heat transport increased by 18%. This increase will have contributed to the observed warming and sea ice decline in the Arctic.
A. S. A. Ferreira, H. Hátún, F. Counillon, M. R. Payne, and A. W. Visser
Biogeosciences, 12, 3641–3653, https://doi.org/10.5194/bg-12-3641-2015, https://doi.org/10.5194/bg-12-3641-2015, 2015
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Our main objective was to assess which bottom-up processes can best predict changes in phytoplankton surface spring blooms in the North Atlantic. We applied new phenology algorithms to satellite-derived data and compared four different metrics based on physical drivers of phytoplankton. We show that there is a dominant physical mechanism - mixed layer shoaling - and that different regions are governed by different physical phenomena.
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
A stable Faroe Bank Channel overflow 1995–2015
Compensation between meridional flow components of the Atlantic MOC at 26° N
Deep drivers of mesoscale circulation in the central Rockall Trough
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
Short summary
Short summary
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, 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
Short summary
Short summary
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.
T. J. Sherwin, D. Aleynik, E. Dumont, and M. E. Inall
Ocean Sci., 11, 343–359, https://doi.org/10.5194/os-11-343-2015, https://doi.org/10.5194/os-11-343-2015, 2015
Short summary
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.
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
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.
On its way towards the Arctic, an important branch of warm Atlantic water passes through the...
