Articles | Volume 19, issue 5
https://doi.org/10.5194/cp-19-1101-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/cp-19-1101-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
01 Jun 2023
Research article |
| 01 Jun 2023
| 01 Jun 2023
Buoyancy forcing: a key driver of northern North Atlantic sea surface temperature variability across multiple timescales
Bjørg Risebrobakken
CORRESPONDING AUTHOR
NORCE Norwegian Research Center, Bjerknes Centre for Climate Research, Bergen, Norway
Mari F. Jensen
Department of Earth Sciences, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway
Helene R. Langehaug
Nansen Environmental and Remote Sensing Center, Bjerknes Centre for
Climate Research, Bergen, Norway
Tor Eldevik
Geophysical Institute, University of Bergen and Bjerknes Centre for
Climate Research, Bergen, Norway
Anne Britt Sandø
Institute of Marine Research, Bjerknes Centre for Climate Research,
Bergen, Norway
Camille Li
Geophysical Institute, University of Bergen and Bjerknes Centre for
Climate Research, Bergen, Norway
Andreas Born
Department of Earth Sciences, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway
Erin Louise McClymont
Department of Geography, Durham University, Durham, UK
Ulrich Salzmann
Department of Geography and Environmental Sciences, Northumbria
University, Newcastle upon Tyne, UK
Stijn De Schepper
NORCE Norwegian Research Center, Bjerknes Centre for Climate Research, Bergen, Norway
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Lauren E. Burton, Alan M. Haywood, Julia C. Tindall, Aisling M. Dolan, Daniel J. Hill, Erin L. McClymont, Sze Ling Ho, and Heather L. Ford
Clim. Past, 20, 1177–1194, https://doi.org/10.5194/cp-20-1177-2024, https://doi.org/10.5194/cp-20-1177-2024, 2024
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Gustav Jungdal-Olesen, Jane Lund Andersen, Andreas Born, and Vivi Kathrine Pedersen
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Anna Hauge Braaten, Kim A. Jakob, Sze Ling Ho, Oliver Friedrich, Eirik Vinje Galaasen, Stijn De Schepper, Paul A. Wilson, and Anna Nele Meckler
Clim. Past, 19, 2109–2125, https://doi.org/10.5194/cp-19-2109-2023, https://doi.org/10.5194/cp-19-2109-2023, 2023
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Clim. Past, 19, 1359–1381, https://doi.org/10.5194/cp-19-1359-2023, https://doi.org/10.5194/cp-19-1359-2023, 2023
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Stephen Outten, Camille Li, Martin P. King, Lingling Suo, Peter Y. F. Siew, Hoffman Cheung, Richard Davy, Etienne Dunn-Sigouin, Tore Furevik, Shengping He, Erica Madonna, Stefan Sobolowski, Thomas Spengler, and Tim Woollings
Weather Clim. Dynam., 4, 95–114, https://doi.org/10.5194/wcd-4-95-2023, https://doi.org/10.5194/wcd-4-95-2023, 2023
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Strong disagreement exists in the scientific community over the role of Arctic sea ice in shaping wintertime Eurasian cooling. The observed Eurasian cooling can arise naturally without sea-ice loss but is expected to be a rare event. We propose a framework that incorporates sea-ice retreat and natural variability as contributing factors. A helpful analogy is of a dice roll that may result in cooling, warming, or anything in between, with sea-ice loss acting to load the dice in favour of cooling.
Tim Woollings, Camille Li, Marie Drouard, Etienne Dunn-Sigouin, Karim A. Elmestekawy, Momme Hell, Brian Hoskins, Cheikh Mbengue, Matthew Patterson, and Thomas Spengler
Weather Clim. Dynam., 4, 61–80, https://doi.org/10.5194/wcd-4-61-2023, https://doi.org/10.5194/wcd-4-61-2023, 2023
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Julia C. Tindall, Alan M. Haywood, Ulrich Salzmann, Aisling M. Dolan, and Tamara Fletcher
Clim. Past, 18, 1385–1405, https://doi.org/10.5194/cp-18-1385-2022, https://doi.org/10.5194/cp-18-1385-2022, 2022
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The mid-Pliocene (MP; ∼3.0 Ma) had CO2 levels similar to today and average temperatures ∼3°C warmer. At terrestrial high latitudes, MP temperatures from climate models are much lower than those reconstructed from data. This mismatch occurs in the winter but not the summer. The winter model–data mismatch likely has multiple causes. One novel cause is that the MP climate may be outside the modern sample, and errors could occur when using information from the modern era to reconstruct climate.
Michael Amoo, Ulrich Salzmann, Matthew J. Pound, Nick Thompson, and Peter K. Bijl
Clim. Past, 18, 525–546, https://doi.org/10.5194/cp-18-525-2022, https://doi.org/10.5194/cp-18-525-2022, 2022
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Late Eocene to earliest Oligocene (37.97–33.06 Ma) climate and vegetation dynamics around the Tasmanian Gateway region reveal that changes in ocean circulation due to accelerated deepening of the Tasmanian Gateway may not have been solely responsible for the changes in terrestrial climate and vegetation; a series of regional and global events, including a change in stratification of water masses and changes in pCO2, may have played significant roles.
Erin L. McClymont, Michael J. Bentley, Dominic A. Hodgson, Charlotte L. Spencer-Jones, Thomas Wardley, Martin D. West, Ian W. Croudace, Sonja Berg, Darren R. Gröcke, Gerhard Kuhn, Stewart S. R. Jamieson, Louise Sime, and Richard A. Phillips
Clim. Past, 18, 381–403, https://doi.org/10.5194/cp-18-381-2022, https://doi.org/10.5194/cp-18-381-2022, 2022
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Sea ice is important for our climate system and for the unique ecosystems it supports. We present a novel way to understand past Antarctic sea-ice ecosystems: using the regurgitated stomach contents of snow petrels, which nest above the ice sheet but feed in the sea ice. During a time when sea ice was more extensive than today (24 000–30 000 years ago), we show that snow petrel diet had varying contributions of fish and krill, which we interpret to show changing sea-ice distribution.
Nick Thompson, Ulrich Salzmann, Adrián López-Quirós, Peter K. Bijl, Frida S. Hoem, Johan Etourneau, Marie-Alexandrine Sicre, Sabine Roignant, Emma Hocking, Michael Amoo, and Carlota Escutia
Clim. Past, 18, 209–232, https://doi.org/10.5194/cp-18-209-2022, https://doi.org/10.5194/cp-18-209-2022, 2022
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We simulated the surface mass balance of the Greenland Ice Sheet in the 21st century by forcing a snow model with the output of many Earth system models and four greenhouse gas emission scenarios. We quantify the contribution to uncertainty in surface mass balance of these two factors and the choice of parameters of the snow model. The results show that the differences between Earth system models are the main source of uncertainty. This effect is localised mostly near the equilibrium line.
Clio Michel, Erica Madonna, Clemens Spensberger, Camille Li, and Stephen Outten
Weather Clim. Dynam., 2, 1131–1148, https://doi.org/10.5194/wcd-2-1131-2021, https://doi.org/10.5194/wcd-2-1131-2021, 2021
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Climate models still struggle to correctly represent blocking frequency over the North Atlantic–European domain. This study makes use of five large ensembles of climate simulations and the ERA-Interim reanalyses to investigate the Greenland blocking frequency and one of its drivers, namely cyclonic Rossby wave breaking. We particularly try to understand the discrepancies between two specific models, out of the five, that behave differently.
Ingo Bethke, Yiguo Wang, François Counillon, Noel Keenlyside, Madlen Kimmritz, Filippa Fransner, Annette Samuelsen, Helene Langehaug, Lea Svendsen, Ping-Gin Chiu, Leilane Passos, Mats Bentsen, Chuncheng Guo, Alok Gupta, Jerry Tjiputra, Alf Kirkevåg, Dirk Olivié, Øyvind Seland, Julie Solsvik Vågane, Yuanchao Fan, and Tor Eldevik
Geosci. Model Dev., 14, 7073–7116, https://doi.org/10.5194/gmd-14-7073-2021, https://doi.org/10.5194/gmd-14-7073-2021, 2021
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The Norwegian Climate Prediction Model version 1 (NorCPM1) is a new research tool for performing climate reanalyses and seasonal-to-decadal climate predictions. It adds data assimilation capability to the Norwegian Earth System Model version 1 (NorESM1) and has contributed output to the Decadal Climate Prediction Project (DCPP) as part of the sixth Coupled Model Intercomparison Project (CMIP6). We describe the system and evaluate its baseline, reanalysis and prediction performance.
Andreas Born and Alexander Robinson
The Cryosphere, 15, 4539–4556, https://doi.org/10.5194/tc-15-4539-2021, https://doi.org/10.5194/tc-15-4539-2021, 2021
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Ice penetrating radar reflections from the Greenland ice sheet are the best available record of past accumulation and how these layers have been deformed over time by the flow of ice. Direct simulations of this archive hold great promise for improving our models and for uncovering details of ice sheet dynamics that neither models nor data could achieve alone. We present the first three-dimensional ice sheet model that explicitly simulates individual layers of accumulation and how they deform.
Erica Madonna, David S. Battisti, Camille Li, and Rachel H. White
Weather Clim. Dynam., 2, 777–794, https://doi.org/10.5194/wcd-2-777-2021, https://doi.org/10.5194/wcd-2-777-2021, 2021
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The amount of precipitation over Europe varies substantially from year to year, with impacts on crop yields and energy production. In this study, we show that it is possible to infer much of the winter precipitation and temperature signal over Europe by knowing only the frequency of occurrence of certain atmospheric circulation patterns. The results highlight the importance of (daily) weather for understanding and interpreting seasonal signals.
Martin P. King, Camille Li, and Stefan Sobolowski
Weather Clim. Dynam., 2, 759–776, https://doi.org/10.5194/wcd-2-759-2021, https://doi.org/10.5194/wcd-2-759-2021, 2021
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We re-examine the uncertainty of ENSO teleconnection to the North Atlantic by considering the November–December and January–February months in the cold season, in addition to the conventional DJF months. This is motivated by previous studies reporting varying teleconnected atmospheric anomalies and the mechanisms concerned. Our results indicate an improved confidence in the patterns of the teleconnection. The finding may also have implications on research in predictability and climate impact.
Daniel J. Lunt, Deepak Chandan, Alan M. Haywood, George M. Lunt, Jonathan C. Rougier, Ulrich Salzmann, Gavin A. Schmidt, and Paul J. Valdes
Geosci. Model Dev., 14, 4307–4317, https://doi.org/10.5194/gmd-14-4307-2021, https://doi.org/10.5194/gmd-14-4307-2021, 2021
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Often in science we carry out experiments with computers in which several factors are explored, for example, in the field of climate science, how the factors of greenhouse gases, ice, and vegetation affect temperature. We can explore the relative importance of these factors by
swapping in and outdifferent values of these factors, and can also carry out experiments with many different combinations of these factors. This paper discusses how best to analyse the results from such experiments.
Tobias Zolles and Andreas Born
The Cryosphere, 15, 2917–2938, https://doi.org/10.5194/tc-15-2917-2021, https://doi.org/10.5194/tc-15-2917-2021, 2021
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We investigate the sensitivity of a glacier surface mass and the energy balance model of the Greenland ice sheet for the cold period of the Last Glacial Maximum (LGM) and the present-day climate. The results show that the model sensitivity changes with climate. While for present-day simulations inclusions of sublimation and hoar formation are of minor importance, they cannot be neglected during the LGM. To simulate the surface mass balance over long timescales, a water vapor scheme is necessary.
Charlotte L. Spencer-Jones, Erin L. McClymont, Nicole J. Bale, Ellen C. Hopmans, Stefan Schouten, Juliane Müller, E. Povl Abrahamsen, Claire Allen, Torsten Bickert, Claus-Dieter Hillenbrand, Elaine Mawbey, Victoria Peck, Aleksandra Svalova, and James A. Smith
Biogeosciences, 18, 3485–3504, https://doi.org/10.5194/bg-18-3485-2021, https://doi.org/10.5194/bg-18-3485-2021, 2021
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Long-term ocean temperature records are needed to fully understand the impact of West Antarctic Ice Sheet collapse. Glycerol dialkyl glycerol tetraethers (GDGTs) are powerful tools for reconstructing ocean temperature but can be difficult to apply to the Southern Ocean. Our results show active GDGT synthesis in relatively warm depths of the ocean. This research improves the application of GDGT palaeoceanographic proxies in the Southern Ocean.
Huiling Zou, Yongqi Gao, Helene R. Langehaug, Lei Yu, and Dong Guo
Ocean Sci. Discuss., https://doi.org/10.5194/os-2021-16, https://doi.org/10.5194/os-2021-16, 2021
Publication in OS not foreseen
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This work focuses on the the relationships between winter sea ice variability and thermodynamic processes in sea ice in the Bering Sea. It has been found that in the Norwegian Earth System Model, thermodynamics in sea ice plays an important role in winter sea ice variability and they can contribute over 70 % of winter sea ice mass incresea in the Bering Sea. The results can be very helpful to give a better understanding of sea ice changes in an Earth System Model.
David K. Hutchinson, Helen K. Coxall, Daniel J. Lunt, Margret Steinthorsdottir, Agatha M. de Boer, Michiel Baatsen, Anna von der Heydt, Matthew Huber, Alan T. Kennedy-Asser, Lutz Kunzmann, Jean-Baptiste Ladant, Caroline H. Lear, Karolin Moraweck, Paul N. Pearson, Emanuela Piga, Matthew J. Pound, Ulrich Salzmann, Howie D. Scher, Willem P. Sijp, Kasia K. Śliwińska, Paul A. Wilson, and Zhongshi Zhang
Clim. Past, 17, 269–315, https://doi.org/10.5194/cp-17-269-2021, https://doi.org/10.5194/cp-17-269-2021, 2021
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The Eocene–Oligocene transition was a major climate cooling event from a largely ice-free world to the first major glaciation of Antarctica, approximately 34 million years ago. This paper reviews observed changes in temperature, CO2 and ice sheets from marine and land-based records at this time. We present a new model–data comparison of this transition and find that CO2-forced cooling provides the best explanation of the observed global temperature changes.
Xavier Fettweis, Stefan Hofer, Uta Krebs-Kanzow, Charles Amory, Teruo Aoki, Constantijn J. Berends, Andreas Born, Jason E. Box, Alison Delhasse, Koji Fujita, Paul Gierz, Heiko Goelzer, Edward Hanna, Akihiro Hashimoto, Philippe Huybrechts, Marie-Luise Kapsch, Michalea D. King, Christoph Kittel, Charlotte Lang, Peter L. Langen, Jan T. M. Lenaerts, Glen E. Liston, Gerrit Lohmann, Sebastian H. Mernild, Uwe Mikolajewicz, Kameswarrao Modali, Ruth H. Mottram, Masashi Niwano, Brice Noël, Jonathan C. Ryan, Amy Smith, Jan Streffing, Marco Tedesco, Willem Jan van de Berg, Michiel van den Broeke, Roderik S. W. van de Wal, Leo van Kampenhout, David Wilton, Bert Wouters, Florian Ziemen, and Tobias Zolles
The Cryosphere, 14, 3935–3958, https://doi.org/10.5194/tc-14-3935-2020, https://doi.org/10.5194/tc-14-3935-2020, 2020
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We evaluated simulated Greenland Ice Sheet surface mass balance from 5 kinds of models. While the most complex (but expensive to compute) models remain the best, the faster/simpler models also compare reliably with observations and have biases of the same order as the regional models. Discrepancies in the trend over 2000–2012, however, suggest that large uncertainties remain in the modelled future SMB changes as they are highly impacted by the meltwater runoff biases over the current climate.
Erin L. McClymont, Heather L. Ford, Sze Ling Ho, Julia C. Tindall, Alan M. Haywood, Montserrat Alonso-Garcia, Ian Bailey, Melissa A. Berke, Kate Littler, Molly O. Patterson, Benjamin Petrick, Francien Peterse, A. Christina Ravelo, Bjørg Risebrobakken, Stijn De Schepper, George E. A. Swann, Kaustubh Thirumalai, Jessica E. Tierney, Carolien van der Weijst, Sarah White, Ayako Abe-Ouchi, Michiel L. J. Baatsen, Esther C. Brady, Wing-Le Chan, Deepak Chandan, Ran Feng, Chuncheng Guo, Anna S. von der Heydt, Stephen Hunter, Xiangyi Li, Gerrit Lohmann, Kerim H. Nisancioglu, Bette L. Otto-Bliesner, W. Richard Peltier, Christian Stepanek, and Zhongshi Zhang
Clim. Past, 16, 1599–1615, https://doi.org/10.5194/cp-16-1599-2020, https://doi.org/10.5194/cp-16-1599-2020, 2020
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We examine the sea-surface temperature response to an interval of climate ~ 3.2 million years ago, when CO2 concentrations were similar to today and the near future. Our geological data and climate models show that global mean sea-surface temperatures were 2.3 to 3.2 ºC warmer than pre-industrial climate, that the mid-latitudes and high latitudes warmed more than the tropics, and that the warming was particularly enhanced in the North Atlantic Ocean.
Cited articles
Alexander, M. A., Scott, J. D., Friedland, K. D., Mills, K. E., Nye, J. A.,
Pershing, A. J., and Thomas, A. C.: Projected sea surface temperatures over
the 21st century: Changes in the mean, variability and extremes for large
marine ecosystem regions of Northern Oceans, Elem. Sci. Anth., 6, 9, https://doi.org/10.1525/elementa.191 2018.
Årthun, M. and Eldevik, T.: On Anomalous Ocean Heat Transport toward the
Arctic and Associated Climate Predictability, J. Climate, 29,
689–704, 2016.
Årthun, M., Eldevik, T., Viste, E., Drange, H., Furevik, T., Johnson, H.
L., and Keenlyside, N.: Skilful prediction of northern climate provided by
the ocean, Nat. Commun., 8, 15875, https://doi.org/10.1038/ncomms15875, 2017.
Bachem, P., Risebrobakken, B., and McClymont, E. L.: Sea surface temperature
variability in the Norwegian Sea during the late Pliocene linked to subpolar
gyre and radiative forcing, Earth Planet. Sc. Lett., 446,
113–122, 2016.
Bachem, P. E., Risebrobakken, B., De Schepper, S., and McClymont, E. L.: Highly variable Pliocene sea surface conditions in the Norwegian Sea, Clim. Past, 13, 1153–1168, https://doi.org/10.5194/cp-13-1153-2017, 2017.
Bartoli, G., Hönisch, B., and Zeebe, R. E.: Atmospheric CO2 decline
during the Pliocene intensification of Northern Hemisphere glaciations,
Paleoceanography, 26, PA4213, https://doi.org/10.1029/2010PA002055, 2011.
Bell, D. B., Jung, S. J. A., Kroon, D., Hodell, D. A., Lourens, L. J., and
Raymo, M. E.: Atlantic Deep-water Response to the Early Pliocene Shoaling of
the Central American Seaway, Sci. Rep., 5, 12252, https://doi.org/10.1038/srep12252, 2015.
Bendle, J. and Rosell-Melé, A.: Distribution of
Blaschek, M., Bakker, P., and Renssen, H.: The influence of Greenland ice
sheet melting on the Atlantic meridional overturning circulation during past
and future warm periods: a model study, Clim. Dynam., 44, 2137–2157,
https://doi.org/10.1007/s00382-014-2279-1, 2015.
Blindheim, J. and Østerhus, S.: The Nordic Seas, Main Oceanographic
Features, in: The Nordic Seas: An integrated Perspective, edited by: Drange,
H., Dokken, T., Furevik, T., Gerdes, R., and Berger, W., Geophysical
Monograph Series, American Geophysical Union, Washington, DC, 11–38, https://doi.org/10.1029/158GM03, 2005.
Bourke, R. H., Weigel, A. M., and Paquette, R. G.: The Westward Turning
Branch of the West Spitsbergen Current, J. Geophys. Res., 93,
14065–14077, 1988.
Bringedal, C., Eldevik, T., Skagseth, Ø., Spall, M., and Østerhus, S.:
Structure and forcing of observed exchanges across the Greenland-Scotland
Ridge, J. Climate, 31, 9881–9901, https://doi.org/10.1175/JCLI-D-17-0889.1, 2018.
Butt, F. A., Drange, H., Elverhøi, A., Otterå, O. H., and Solheim,
A.: Modelling Late Cenozoic isostatic elevation changes in the Barents Sea
and their implications for oceanic and climatic regimes: preliminary
results, Quaternary Sci. Rev., 21, 1643–1660, 2002.
Clotten, C.: Pliocene Sea Ice Evolution in the Iceland and Labrador Sea – A
Biomarker Approach, PhD, Department of Earth Science, Faculty of Mathematics
and Natural Sciences, University of Bergen, Bergen, 145 pp., ISBN 978-82-308-3888-4, 2017.
Clotten, C., Stein, R., Fahl, K., and De Schepper, S.: Seasonal sea ice
cover during the warm Pliocene: Evidence from the Iceland Srea (ODP Site
907), Earth Planet. Sc. Lett., 481, 61–72, https://doi.org/10.1016/j.epsl.2017.10.011, 2018.
Clotten, C., Stein, R., Fahl, K., Schreck, M., Risebrobakken, B., and De
Schepper, S.: On the causes of Sea Ice in the warm Early Pliocene, Sci. Rep., 9, 989, https://doi.org/10.1038/s41598-018-37047-y, 2019.
Conte, M. H., Sicre, M.-A., Rühlemann, C., Weber, J. C., Schulte, S.,
Schulz-Bull, D. E., and Blanz, T.: Global temperature calibration of the
alkenone unsaturation index (
de la Vega, E., Chalk, T. B., Wilson, P. A., Bysani, R. P., and Foster, G.
L.: Atmospheric CO2 during the Mid-Piacenzian Warm Period and the M2
glaciation, Sci. Rep., 10, 11002, https://doi.org/10.1038/s41598-020-67154-8, 2020.
DeRepentigny, P., Jahn, A., Holland, M. M., and Smith, A.: Arctic sea ice in
two configurations of the CESM2 during the 20th and 21st centuries, J.
Geophys. Res.-Ocean, 125, e2020JC016133, https://doi.org/10.1029/2020JC016133, 2020.
De Schepper, S., Schreck, M., Beck, K. M., Matthiessen, J., Fahl, K., and
Mangerud, G.: Early Pliocene onset of modern Nordic Seas circulation related
to ocean gateway changes, Nat. Commun., 6, 8659,
https://doi.org/10.1038/ncomms9659, 2015.
Dickson, R. R., Meincke, J., Malmberg, S. A., and Lee, J. A.: The “Great
Salinity Anomaly” in the northern North Atlantic 1968–1982, Progress in
Oceanography, 20, 103–151, 1988.
Eldevik, T. and Nilsen, J. E. Ø.: The Arctic/Atlantic thermohaline
circulation, J. Climate, 26, 8698–8705,
https://doi.org/10.1175/JCLI-D-13-00305.1, 2013.
Eldevik, T., Nilsen, J. E. Ø., Iovino, D., Olsson, K. A., Sandø, A.
B., and Drange, H.: Observed sources and variability of the Nordic Seas
overflow, Nat. Geosci., 2, 406–410, 2009.
Furevik, T., Drange, H., and Sorteberg, A.: Anticipated changes in the
Nordic Seas marine climate: Scenarios for 2020, 2050, and 2080, Fisken og
Havet, 4, http://hdl.handle.net/11250/113241 (last access: 24 May 2023), 2002.
Furevik, T., Mauritzen, C., and Ingvaldsen, R.: The flow of Atlantic Water
to the Nordic Seas and Arctic Ocean, in: Arctic-Alpine Ecosystems and People
in a Changing Environment, edited by: Ørbæk, J. B., Kallenborn, R.,
Tombre, I., Nøst Hegseth, E., Falk-Petersen, S., and Hoel, A. H.,
Springer, 123–146, https://doi.org/10.1007/978-3-540-48514-8_8, 2007.
Hátún, H., Sandø, A. B., Drange, H., Hansen, B., and
Valdimarsson, H.: Influence of the Atlantic Subpolar Gyre on the
Thermohaline Circulation, Science, 309, 1841–1844, 2005.
Herbert, T. D., Lawrence, K. T., Tzanova, A., Peterson, L. C.,
Caballero-Gill, R., and Kelly, C. S.: Late Miocene global cooling and the
rise of modern ecosystems, Nat. Geosci., 9, 843–849, 2016.
Holliday, N. P., Hughes, S. L., Bacon, S., Beszczynska-Möller, A.,
Hansen, A. W., Lavin, H., Loeng, H., Mork, K. A., Østerhus, S., Sherwin,
T., and Walczowski, W.: Reversal of the 1960s to1990s freshening trend in
the northeast North Atlantic and Nordic Seas, Geophys. Res. Lett., 35, L03614, https://doi.org/10.1029/2007GL032675, 2008.
Hu, A., Meehl, G. A., Han, W., Otto-Bliesner, B., Abe-Ouchi, A., and
Rosenbloom, N.: Effects of the Bering Strait closure on AMOC and global
climate under different background climates, Prog. Oceanogr., 132,
174–196, https://doi.org/10.1016/j.pocean.2014.02.004, 2015.
IPCC: Climate Change 2021: The Physical Science Basis, in: Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Masson-Delmotte, V., Zhai, P., Pirani, A., Connors, S. L., Péan, C., Berger, S., Caud, N., Chen, Y., Goldfarb, L., Gomis, M. I., Huang, M., Leitzell, K., Lonnoy, E., Matthews, J. B. R., Maycock, T. K., Waterfield, T., Yelekçi, O., Yu, R., and Zhou, B., Cambridge University Press, Cambridge, UK and New York, NY, USA, 2391 pp., https://doi.org/10.1017/9781009157896, 2021.
is-enes: Analysis Platforms for CMIP6 and CORDEX, https://is.enes.org/sdm-analysis-platforms-service/ (last access: 26 May 2023), 2023.
Jackett, D. R. and McDougall, T. J.: Minimal adjustment of hydrographic
profiles to achieve static stability, J. Atmos. Ocean. Tech., 12,
381–389, 1995.
Jansen, E., Fronval, T., Rack, F., and Channell, J. E. T.:
Pliocene-Pleistocene ice rafting history and cyclicity in the Nordic Seas
during the last 3.5 Myr, Paleoceanography, 15, 709–721, 2000.
Keil, P., Mauritsen, T., Jungclaus, J., Hedemann, C., Olonschenck, D., and
Ghosh, R.: Multiple drivers of the North Atlantic warming hole, Nat.
Clim. Change, 10, 667–671, 2020.
Knies, J., Cabedo-Sanz, P., Belt, S. T., Baranwal, S., Fietz, S., and
Rosell-Melé, A.: The emergence of modern sea ice cover in the Arctic
Ocean, Nat. Commun., 5, 5608, https://doi.org/10.1038/ncomms6608, 2014.
Knight, J. R., Allan, R. J., Folland, C. K., Vellinga, M., and Mann, M. E.:
A signature of persistent natural thermohaline circulation cycles in
observed climate, Geophys. Res. Lett., 32, L20708, https://doi.org/10.1029/2005GL024233, 2005.
Kwiatkowski, L., Torres, O., Bopp, L., Aumont, O., Chamberlain, M., Christian, J. R., Dunne, J. P., Gehlen, M., Ilyina, T., John, J. G., Lenton, A., Li, H., Lovenduski, N. S., Orr, J. C., Palmieri, J., Santana-Falcón, Y., Schwinger, J., Séférian, R., Stock, C. A., Tagliabue, A., Takano, Y., Tjiputra, J., Toyama, K., Tsujino, H., Watanabe, M., Yamamoto, A., Yool, A., and Ziehn, T.: Twenty-first century ocean warming, acidification, deoxygenation, and upper-ocean nutrient and primary production decline from CMIP6 model projections, Biogeosciences, 17, 3439–3470, https://doi.org/10.5194/bg-17-3439-2020, 2020.
Lawrence, K. T., Herbert, T. D., Brown, C. W., Raymo, M., and Haywood, A.
M.: High-amplitude variations in North Atlantic sea surface temperature
during the early Pliocene warm period, Paleoceanography, 24, PA2218,
https://doi.org/10.1029/2008PA001669, 2009.
Lisiecki, L. E. and Raymo, M. E.: A Pliocene-Pleistocene stack of 57 globally distributed benthic δ18O records, Paleoceanography, 20, PA1003, https://doi.org/10.1029/2004PA001071, 2005.
Locarini, R. A., Mishonov, A. V., Baranova, O. K., Boyer, T. P., Zweng, M.
M., Garcia, H. E., Reagan, J. R., Seidov, D., Weathers, K., Paver, C. R.,
and Smolyar, I.: World Ocean Atlas 2018, Volume 1, Temperature, 52, http://www.nodc.noaa.gov/OC5/indprod.html (last access: 20 May 2021), 2018.
Macrander, A., Valdimarsson, H., and Jónsson, S.: Improved transport
estimate of the East Icelandic Current 2002–2012, J. Geophys.
Res.-Oceans, 119, 3407–3424, https://doi.org/10.1002/2013JC009517, 2014.
Marlowe, I. T., Brassell, S. C., Eglinton, G., and Green, J. C.: Long chain
unsaturated ketons and esters in living algae and marien sediments, Ketones, 6, 135–141, 1984.
Marshall, J., Hill, C., Perelman, L., and Adcroft, A.: Hydro-static,
quasi-hydrostatic, and non-hydrostatic ocean modeling, J.
Geophys. Res., 102, 5733–5752, 1997.
Matthiessen, J., Knies, J., Vogt, C., and Stein, R.: Pliocene
paleoceanography of the Arctic Ocean and subarctic seas, Philos. T. R.
Soc. A, 367, 21–48, 2009.
Mauritzen, C.: Production of dense overflow waters feeding the North
Atlantic across the Greenland-Scotland Ridge. Part 1: Evidence for a revised
circulation scheme, Deep-Sea Res. Pt. I, 43, 769–837, 1996.
McClymont, E. L., Ford, H. L., Ho, S. L., Tindall, J. C., Haywood, A. M., Alonso-Garcia, M., Bailey, I., Berke, M. A., Littler, K., Patterson, M. O., Petrick, B., Peterse, F., Ravelo, A. C., Risebrobakken, B., De Schepper, S., Swann, G. E. A., Thirumalai, K., Tierney, J. E., van der Weijst, C., White, S., Abe-Ouchi, A., Baatsen, M. L. J., Brady, E. C., Chan, W.-L., Chandan, D., Feng, R., Guo, C., von der Heydt, A. S., Hunter, S., Li, X., Lohmann, G., Nisancioglu, K. H., Otto-Bliesner, B. L., Peltier, W. R., Stepanek, C., and Zhang, Z.: Lessons from a high-CO2 world: an ocean view from ∼3 million years ago, Clim. Past, 16, 1599–1615, https://doi.org/10.5194/cp-16-1599-2020, 2020.
Meehl, G. A., Senior, C. A., Eyring, V., Flato, G., Lamarque, J.-F.,
Stouffer, R. J., Taylor, K. E., and Schlund, M.: Context for interpreting
equilibrium climate sensitivity and transient climate response from the
CMIP6 Earth system models, Science Advances, 6, eaba1981,
https://doi.org/10.1126/sciadv.aba1981, 2020.
Meinshausen, M., Nicholls, Z. R. J., Lewis, J., Gidden, M. J., Vogel, E., Freund, M., Beyerle, U., Gessner, C., Nauels, A., Bauer, N., Canadell, J. G., Daniel, J. S., John, A., Krummel, P. B., Luderer, G., Meinshausen, N., Montzka, S. A., Rayner, P. J., Reimann, S., Smith, S. J., van den Berg, M., Velders, G. J. M., Vollmer, M. K., and Wang, R. H. J.: The shared socio-economic pathway (SSP) greenhouse gas concentrations and their extensions to 2500, Geosci. Model Dev., 13, 3571–3605, https://doi.org/10.5194/gmd-13-3571-2020, 2020.
Met Office Hadley Centre: Hadley Centre Sea Ice and Sea Surface Temperature data set (HadISST), Met Office Hadley Centre [data set], https://www.metoffice.gov.uk/hadobs/hadisst/ (last access: May 2013), 2013.
MITgcm: Massachusetts Institute of Technology General Circulation Model, https://mitgcm.org (last access: August 2022), 2023.
Müller, P. J., Kirst, G., Ruhland, G., Vvon Storch, I., and
Rosell-Melé, A.: Calibration of the alkenone paleotemperature index
Nummelin, A., Li, C., and Hezel, P. J.: Connecting ocean heat transport
changes from the midlatitudes to the Arctic Ocean, Geophys. Res. Lett., 44, 1899–1908, https://doi.org/10.1002/2016GL071333, 2017.
O'Neill, B. C., Tebaldi, C., van Vuuren, D. P., Eyring, V., Friedlingstein, P., Hurtt, G., Knutti, R., Kriegler, E., Lamarque, J.-F., Lowe, J., Meehl, G. A., Moss, R., Riahi, K., and Sanderson, B. M.: The Scenario Model Intercomparison Project (ScenarioMIP) for CMIP6, Geosci. Model Dev., 9, 3461–3482, https://doi.org/10.5194/gmd-9-3461-2016, 2016.
Otto-Bliesner, B., Jahn, A., Feng, R., Brady, E. C., Hu, A., and
Löfverström, M.: Amplified North Atlantic warming in the late
Pliocene by changes in Arctic gateways, Geophys. Res. Lett., 44, 957–964,
https://doi.org/10.1002/2016GL071805, 2016.
Paillard, D., Labeyrie, L., and Yiou, P.: Macintosh program performs
time-series analysis, EOS T. AGU, 79, 379–379, 1996.
Panitz, S., Salzmann, U., Risebrobakken, B., De Schepper, S., Pound, J. M.,
Haywood, A., Dolan, A. M., and Lunt, D.: Orbital, tectonic and oceanographic
control of Pliocene climate and atmospheric circulation in Arctic Norway,
Global Planet. Change, 161, 183–193, 2018.
Poore, H. R., Samworth, R., White, N. J., Jones, S. M., and McCave, I. N.:
Neogene overflow of Northern Component Water at the Greenland-Scotland
Ridge, Geochem. Geophy. Geosy., 7, Q06010, https://doi.org/10.1029/2005GC001085, 2006.
Prahl, F. G. and Wakeham, S. G.: Calibration of unsaturation patterns in
long-chain ketone compositions for paleotemperature assessment, Nature, 330,
367–369, 1987.
Rayner, N. A., Parker, D. E., Horton, E. B., Folland, C. K., Alexander, L.
V., Rowell, D. P., Kent, E. C., and Kaplan, A.: Global analyses of sea
surface temperature, sea ice, and night marine air temperature since the
late nineteenth century, J. Geophys. Res.-Atmos., 108, 4407,
https://doi.org/10.1029/2002JD002670, 2003.
Reverdin, G.: North Atlantic subpolar gyre surface variability (1895–2009),
J. Climate, 23, 4571–4584, 2010.
Risebrobakken, B., Andersson, C., De Schepper, S., and McClymont, E. L.:
Low-frequency Pliocene climate variability in the eastern Nordic Seas,
Paleoceanography, 31, 1154–1175, https://doi.org/10.1002/2015PA002918, 2016.
Rosell-Melé, A. and Prahl, F. G.: Seasonality of
Rudels, B., Björck, G., Nilsson, J., Winsor, P., Lake, I., and Nohr, C.:
The interaction between waters from the Arctic Ocean and the Nordic Seas
north of Fram Strait and along the East Greenland Current: Results from the
Arctic Ocean-02 Oden expedition, J. Mar. Syst., 55, 1–30, 2005.
Ryan, W. B. F., Carbotte, S. M., Coplan, J., O'Hara, S., Melkonian, A.,
Arko, R., Weissel, R. A., Ferrini, V., Goodwillie, A., Nitsche, F.,
Bonczkowski, J., and Zemsky, R.: Global Multi-Resolution Topography (GMRT)
synthesis data set, Geochem. Gephys. Geosyst., 10, QQ03014, https://doi.org/10.1029/2008GC002332, 2009.
Seidov, D., Baranova, O. K., Biddle, M., Boyer, T. P., Johnson, D. R., Mishonov, A. V., Paver, C., and Zweng, M.: Greenland-Iceland-Norwegian Seas Regional Climatology (NCEI Accession 0112824), NOAA National Centers for Environmental Information [data set], https://doi.org/10.7289/V5GT5K30, 2013.
Seidov, D., Baranova, O. K., Boyer, T. P., Cross, S. L., Mishonov, A. V., Parsons, A. R., Reagan, J. R., and Weathers, K. W.: Greenland-Iceland-Norwegian Seas Regional Climatology version 2, Regional Climatology Team, NOAA/NCEI, https://www.ncei.noaa.gov/products/greenland-iceland-and-norwegian-seas-regional-climatology (last access: 20 May 2021), 2018.
Seland, Ø., Bentsen, M., Olivié, D., Toniazzo, T., Gjermundsen, A., Graff, L. S., Debernard, J. B., Gupta, A. K., He, Y.-C., Kirkevåg, A., Schwinger, J., Tjiputra, J., Aas, K. S., Bethke, I., Fan, Y., Griesfeller, J., Grini, A., Guo, C., Ilicak, M., Karset, I. H. H., Landgren, O., Liakka, J., Moseid, K. O., Nummelin, A., Spensberger, C., Tang, H., Zhang, Z., Heinze, C., Iversen, T., and Schulz, M.: Overview of the Norwegian Earth System Model (NorESM2) and key climate response of CMIP6 DECK, historical, and scenario simulations, Geosci. Model Dev., 13, 6165–6200, https://doi.org/10.5194/gmd-13-6165-2020, 2020.
Smagorinsky, J.: General circulation experiments with the primitive
equations: I. The basic experiment, Mon. Weather Rev., 91, 99–164, 1963.
Smedsrud, L. H., Muilwijk, M., Brakstad, A., Madonna, E., Lauvset, S. K.,
Spensberger, C., Born, A., Eldevik, T., Drange, H., Jeansson, E., Li, C.,
Olsen, A., Skagseth, O., Slater, D. A., Straneo, F., Våge, K., and
Årthun, M.: Nordic Seas Heat Loss, Atlantic Inflow, and Arctic Sea Ice
Cover Over the Last Century, Rev. Geophys., 60, e2020RG000725,
https://doi.org/10.1029/2020RG000725, 2022.
Spall, M. A.: On the role of eddies and surface forcing in the heat
transport and overturning circulation in marginal seas, J. Climate, 24,
4844–4858, https://doi.org/10.1175/2011JCLI4130.1, 2011.
Spall, M. A.: Influences of precipitation on water mass trans-formation and
deep convection, J. Phys. Oceanogr., 42, 1684–1700,
https://doi.org/10.1175/JPO-D-11-0230.1, 2012.
Talley, L. D., Pickard, G. L., Emery, W. J., and Swift, J. H.:
Mass, Salt, and Heat Budgets and Wind Forcing, in: Descriptive Physical
Oceanography (Sixth Edition), chap. 5, edited by: Talley, L. D., Pickard, G. L.,
Emery, W. J., and Swift, J. H., Academic Press, 111–145,
https://doi.org/10.1016/C2009-1010-24322-24324, 2011.
Tierney, J. E. and Tingley, M. P.: BAYSLINE: A new calibration for the
alkenone paleothermometer, Paleoceanography and Paleoclimatology, 33,
281–301, https://210.1002/2017PA003201, 2018.
Våge, K., Pickart, R. S., Spall, M. A., Valdimarsson, H., Jónsson,
S., Torres, D. J., Østerhus, S., and Eldevik, T.: Significant role of the
North Icelandic Jet in the formation of Denmark Strait overflow water,
Nat. Geosci., 4, 723–727, https://doi.org/10.1038/NGEO1234, 2011.
Verhoeven, K., Louwye, S., and Eiríksson, J.: Plio-Pleistocene
landscape and vegetation reconstruction of the coastal area of the
Tjörnes Peninsula, Northern Iceland, Boreas, 42, 108–122, 2013.
WCRP: CMIP6, https://esgf-node.llnl.gov/search/cmip6/ (last access: 9 September 2020), 2020.
Wei, T., Yan, Q., Qi, W., Ding, M., and Wang, C.: Projections of Arctic sea
ice conditions and shipping routes in the twenty-first century using CMIP6
forcing scenarios, Environ. Res. Lett., 15, 104079,
https://doi.org/10.1088/1748-9326/abb2c8, 2020.
Weijer, W., Cheng, W., Garuba, O. A., Hu, A., and Nadiga, B. T.: CMIP6
models predict significant 21st century decline of the Atlantic meridional
overturning circulation, Geophys. Res. Lett., 47, e2019GL086075, https://doi.org/10.1029/2019GL086075, 2020.
Woodgate, R. A. and Aagaard, K.: Revising the Bering Strait freshwater flux
into the Arctic Ocean, Geophys. Res. Lett., 32, L02602,
https://doi.org/10.1029/2004GL021747, 2005.
Zanowski, H., Jahn, A., and Holand, M. M.: Arctic Ocean Freshwater in CMIP6
Ensembles: Declining Sea ice, Increasing Ocean Storage and Export, J.
Geophys. Res.-Oceans, 126, e2020JC016930, https://doi.org/10.1029/2020JC016930, 2021.
Short summary
In the observational period, spatially coherent sea surface temperatures characterize the northern North Atlantic at multidecadal timescales. We show that spatially non-coherent temperature patterns are seen both in further projections and a past warm climate period with a CO2 level comparable to the future low-emission scenario. Buoyancy forcing is shown to be important for northern North Atlantic temperature patterns.
In the observational period, spatially coherent sea surface temperatures characterize the...
