Articles | Volume 15, issue 4
https://doi.org/10.5194/os-15-905-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-15-905-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Bathymetric properties of the Baltic Sea
Martin Jakobsson
CORRESPONDING AUTHOR
Department of Geological Sciences, Stockholm University, Stockholm, 10691, Sweden
Christian Stranne
Department of Geological Sciences, Stockholm University, Stockholm, 10691, Sweden
Matt O'Regan
Department of Geological Sciences, Stockholm University, Stockholm, 10691, Sweden
Sarah L. Greenwood
Department of Geological Sciences, Stockholm University, Stockholm, 10691, Sweden
Bo Gustafsson
The Baltic Sea Centre, Stockholm University, Stockholm, 10691, Sweden
Christoph Humborg
The Baltic Sea Centre, Stockholm University, Stockholm, 10691, Sweden
Elizabeth Weidner
Department of Geological Sciences, Stockholm University, Stockholm, 10691, Sweden
Department of Earth Science, University of New Hampshire, 56 College Road, Durham, NH, USA
Related authors
Jamie Barnett, Felicity A. Holmes, Sarah L. Greenwood, Mathieu Morlighem, Nina Kirchner, and Martin Jakobsson
The Cryosphere, 20, 3599–3617, https://doi.org/10.5194/tc-20-3599-2026, https://doi.org/10.5194/tc-20-3599-2026, 2026
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Computer models used to predict future change of the Greenland Ice Sheet are uncertain, especially in how they represent iceberg calving. We compare several calving approaches by testing model results against satellite observations of changes at three unique floating ice shelves in Greenland. We then extend the simulations to the year 2300 to explore future ice loss, finding that warming of the atmosphere or ocean is more important than the choice of calving method.
Camille Hayatte Akhoudas, Johan Nilsson, William Jenkins, Jamie Barnett, Jürgen Sültenfuß, Nina Kirchner, Martin Jakobsson, and Christian Stranne
EGUsphere, https://doi.org/10.5194/egusphere-2026-1366, https://doi.org/10.5194/egusphere-2026-1366, 2026
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Understanding how freshwater input shapes circulation in Greenland fjords is key to ice-ocean interactions in a warming climate. Using hydrographic measurements, oxygen isotopes, and noble gas tracers, we map water composition and meltwater pathways in the sparsely observed Petermann and Victoria fjords. The results show that most freshwater comes from local glaciers, enters both at the subsurface and deeper layers, and that fjord conditions strongly influence how meltwater spreads and mixes.
Jamie Barnett, Felicity A. Holmes, Joshua Cuzzone, Henning Åkesson, Mathieu Morlighem, Matt O'Regan, Johan Nilsson, Nina Kirchner, and Martin Jakobsson
The Cryosphere, 19, 3631–3653, https://doi.org/10.5194/tc-19-3631-2025, https://doi.org/10.5194/tc-19-3631-2025, 2025
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Understanding how ice sheets have changed in the past can allow us to make better predictions for the future. By running a state-of-the-art model of Ryder Glacier, North Greenland, over the past 12 000 years we find that both a warming atmosphere and the ocean play a key role in the evolution of the glacier. Our conclusions stress that accurately quantifying the ice sheet’s interactions with the ocean is required to predict future changes and reliable sea level rise estimates.
Felicity A. Holmes, Jamie Barnett, Henning Åkesson, Mathieu Morlighem, Johan Nilsson, Nina Kirchner, and Martin Jakobsson
The Cryosphere, 19, 2695–2714, https://doi.org/10.5194/tc-19-2695-2025, https://doi.org/10.5194/tc-19-2695-2025, 2025
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Northern Greenland contains some of the ice sheet's last remaining glaciers with floating ice tongues. One of these is Ryder Glacier, which has been relatively stable in recent decades, in contrast to nearby glaciers. Here, we use a computer model to simulate Ryder Glacier until 2300 under both a low- and a high-emissions scenario. Very high levels of surface melt under a high-emissions future lead to a sea level rise contribution that is an order of magnitude higher than under a low-emissions future.
Julia Muchowski, Martin Jakobsson, Lars Umlauf, Lars Arneborg, Bo Gustafsson, Peter Holtermann, Christoph Humborg, and Christian Stranne
Ocean Sci., 19, 1809–1825, https://doi.org/10.5194/os-19-1809-2023, https://doi.org/10.5194/os-19-1809-2023, 2023
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We show observational data of highly increased mixing and vertical salt flux rates in a sparsely sampled region of the northern Baltic Sea. Co-located acoustic observations complement our in situ measurements and visualize turbulent mixing with high spatial resolution. The observed mixing is generally not resolved in numerical models of the area but likely impacts the exchange of water between the adjacent basins as well as nutrient and oxygen conditions in the Bothnian Sea.
Johan Nilsson, Eef van Dongen, Martin Jakobsson, Matt O'Regan, and Christian Stranne
The Cryosphere, 17, 2455–2476, https://doi.org/10.5194/tc-17-2455-2023, https://doi.org/10.5194/tc-17-2455-2023, 2023
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We investigate how topographical sills suppress basal glacier melt in Greenlandic fjords. The basal melt drives an exchange flow over the sill, but there is an upper flow limit set by the Atlantic Water features outside the fjord. If this limit is reached, the flow enters a new regime where the melt is suppressed and its sensitivity to the Atlantic Water temperature is reduced.
Gabriel West, Darrell S. Kaufman, Martin Jakobsson, and Matt O'Regan
Geochronology, 5, 285–299, https://doi.org/10.5194/gchron-5-285-2023, https://doi.org/10.5194/gchron-5-285-2023, 2023
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We report aspartic and glutamic acid racemization analyses on Neogloboquadrina pachyderma and Cibicidoides wuellerstorfi from the Arctic Ocean (AO). The rates of racemization in the species are compared. Calibrating the rate of racemization in C. wuellerstorfi for the past 400 ka allows the estimation of sample ages from the central AO. Estimated ages are older than existing age assignments (as previously observed for N. pachyderma), confirming that differences are not due to taxonomic effects.
Jaclyn Clement Kinney, Karen M. Assmann, Wieslaw Maslowski, Göran Björk, Martin Jakobsson, Sara Jutterström, Younjoo J. Lee, Robert Osinski, Igor Semiletov, Adam Ulfsbo, Irene Wåhlström, and Leif G. Anderson
Ocean Sci., 18, 29–49, https://doi.org/10.5194/os-18-29-2022, https://doi.org/10.5194/os-18-29-2022, 2022
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We use data crossing Herald Canyon in the Chukchi Sea collected in 2008 and 2014 together with numerical modelling to investigate the circulation in the western Chukchi Sea. A large fraction of water from the Chukchi Sea enters the East Siberian Sea south of Wrangel Island and circulates in an anticyclonic direction around the island. To assess the differences between years, we use numerical modelling results, which show that high-frequency variability dominates the flow in Herald Canyon.
Hermann Bange, Carolin Löscher, Damian Arévalo-Martínez, Stefano Bonaglia, Hanna Farnelid, Bo Gustafsson, Dana Hellemann, Jenny Hieronymus, Peeter Laas, Christian Lønborg, Natalie Loick-Wilde, Volker Matthias, Joseph Montoya, Sofia Saraiva, Vibe Schourup-Kristensen, Beata Szymczycha, Germo Väli, Maren Voss, Mindaugas Zilius, and Malin Olofsson
EGUsphere, https://doi.org/10.5194/egusphere-2026-5940, https://doi.org/10.5194/egusphere-2026-5940, 2026
This preprint is open for discussion and under review for Biogeosciences (BG).
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The nitrogen cycle of the Baltic Sea has received considerable attention over the past five decades mainly due to the ongoing expansion of oxygen-free zones. Here we present a summary of the present state of the nitrogen cycle in the Baltic Sea, identify open research questions and suggest a way forward to address the open questions with the aim to reduce uncertainties in projections of the future nitrogen cycle which, in turn, can advance and help management measures for ecosystem restoration.
Helen K. Coxall, Thomas M. Cronin, Kate Darling, Katrine Husum, Tamara Handl, Brian T. Huber, Megh M. Kanvinde, Mohammad Razmjooei, Flor Vermassen, Antje H. L. Voelker, Tirza M. Weitkamp, and Matt O'Regan
J. Micropalaeontol., 45, 581–622, https://doi.org/10.5194/jm-45-581-2026, https://doi.org/10.5194/jm-45-581-2026, 2026
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Today’s sea-ice-covered Arctic Ocean hosts only one species of calcifying planktonic foraminifera, unlike warmer oceans with diverse communities. Fossils show that other species once inhabited the Arctic, but their identities and environmental significance remain uncertain. Using detailed microscopy and hundreds of shell measurements, we resolve these fossil species and establish a new taxonomic framework providing the foundation for improved reconstructions of Quaternary Arctic climate history.
Jamie Barnett, Felicity A. Holmes, Sarah L. Greenwood, Mathieu Morlighem, Nina Kirchner, and Martin Jakobsson
The Cryosphere, 20, 3599–3617, https://doi.org/10.5194/tc-20-3599-2026, https://doi.org/10.5194/tc-20-3599-2026, 2026
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Computer models used to predict future change of the Greenland Ice Sheet are uncertain, especially in how they represent iceberg calving. We compare several calving approaches by testing model results against satellite observations of changes at three unique floating ice shelves in Greenland. We then extend the simulations to the year 2300 to explore future ice loss, finding that warming of the atmosphere or ocean is more important than the choice of calving method.
Felix Strobel, Gregor Hillers, Tom Jilbert, John Loehr, Christian Stranne, Tahvo Oksanen, Jonathan Vänskä, Roméo Courbis, Annukka Rintamäki, Amir Sadeghi-Bagherabadi, Lasse Weißgräber, Yinshuai Ding, Marc de Langenhagen, Eduardo Valero Cano, Kwabena Atobra, Vicent Doñate Felip, Valtteri Hopiavuori, Max Kankainen, Mohammad Alem Khodadadi, Kauri Kolehmainen, Emma Makkonen, Liisa Nygrén, Eero Purhonen, Niklas Rolleberg, Jasmiina Tuomiranta, Tommi Vuorinen, Aurélien Mordret, Cédric Schmelzbach, Ludovic Moreau, Olivier Coutant, and Céline Hadziioannou
EGUsphere, https://doi.org/10.5194/egusphere-2026-2106, https://doi.org/10.5194/egusphere-2026-2106, 2026
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We describe an experiment to investigate variations of lake ice properties. We put a large number of seismic instruments on a frozen lake to record the ambient ice vibrations and make a range of supporting measurements. The initial results show that environmental effects can be resolved from the vibrations. This includes meteorological changes but also the trapping of methane or other gas bubbles during ice formation, which can help quantify the release of greenhouse gases from lakes.
Albin Eriksson, Junjie Wu, Matt O'Regan, and Örjan Gustafsson
EGUsphere, https://doi.org/10.5194/egusphere-2026-2414, https://doi.org/10.5194/egusphere-2026-2414, 2026
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Sea ice is an important regulator of the Arctic climate systems. Records of sea ice past instrumental records are necessary to understand how sea ice is altered during past periods of abrupt climate change, and what consequences such changes have on the polar climates. Here, we reconstructed the sea ice cover of the East Siberian Arctic and found that the sea ice extent likely was linked to protecting/eroding permafrost coastlines during the last deglaciation.
Camille Hayatte Akhoudas, Johan Nilsson, William Jenkins, Jamie Barnett, Jürgen Sültenfuß, Nina Kirchner, Martin Jakobsson, and Christian Stranne
EGUsphere, https://doi.org/10.5194/egusphere-2026-1366, https://doi.org/10.5194/egusphere-2026-1366, 2026
Short summary
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Understanding how freshwater input shapes circulation in Greenland fjords is key to ice-ocean interactions in a warming climate. Using hydrographic measurements, oxygen isotopes, and noble gas tracers, we map water composition and meltwater pathways in the sparsely observed Petermann and Victoria fjords. The results show that most freshwater comes from local glaciers, enters both at the subsurface and deeper layers, and that fjord conditions strongly influence how meltwater spreads and mixes.
Dana Hellemann, Xiaole Sun, Tom Jilbert, Eva Ehrnsten, Lora Harris, Bo Gustafsson, Christoph Humborg, and Alf Norkko
EGUsphere, https://doi.org/10.5194/egusphere-2026-959, https://doi.org/10.5194/egusphere-2026-959, 2026
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Using model-simulations and field data, we assess the effect of past eutrophication on present and future ammonium dynamics in coastal sediments of the Baltic Sea and their impact on the coastal ecosystem. Our results indicate a clear eutrophication legacy effect on the persistence of ammonium being released from the sediment to the water column, particularly under oxygen deficiency, with long-lasting effects into the far future and thus important implications for ecosystem recovery measures.
Julika Zinke, Joakim P. Hansen, Martijn Hermans, Alexis Fonseca, Sofia A. Wikström, Linda Kumblad, Emil Rydin, Marc Geibel, Matthew E. Salter, and Christoph Humborg
Biogeosciences, 23, 1653–1680, https://doi.org/10.5194/bg-23-1653-2026, https://doi.org/10.5194/bg-23-1653-2026, 2026
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This study presents one of the few studies to simultaneously measure all three major greenhouse gases across multiple shallow coastal bays in the Baltic Sea. Our findings reveal that these bays are highly variable and significant sources of greenhouse gases, with fluxes strongly influenced by bay characteristics and seasonal variation. By linking concentrations to environmental drivers, our work provides novel insights into overlooked but important components of coastal greenhouse gas budgets.
Ankit Pramanik, Sarah L. Greenwood, Mathieu Morlighem, Jamie Barnett, Felicity A. Holmes, Richard Gyllencreutz, and Carl Regnéll
EGUsphere, https://doi.org/10.5194/egusphere-2026-172, https://doi.org/10.5194/egusphere-2026-172, 2026
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Ice sheet/glacier retreat is driving expansion of glacial lakes impounded at the ice margin. Using an ice sheet model, we find that lake filling and drainage causes systematic changes to glacier thickness, velocity and mass loss. Rising lake levels dramatically increase mass loss as the ice margin becomes buoyant, while rapid lake drainage can drive crevassing and destabilise the margin. Steady lake drainage, in contrast, has a stabilising effect, and may mitigate mass loss and flood hazards.
Madeleine Santos, Lisa Bröder, Matt O'Regan, Iván Hernández-Almeida, Tommaso Tesi, Lukas Bigler, Negar Haghipour, Daniel B. Nelson, Michael Fritz, and Julie Lattaud
Clim. Past, 22, 187–203, https://doi.org/10.5194/cp-22-187-2026, https://doi.org/10.5194/cp-22-187-2026, 2026
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Our study examined how sea ice in the Beaufort Sea has changed over the past 13 000 years to better understand today's rapid losses. By analyzing chemical tracers preserved in seafloor sediments, we found that the Early Holocene was largely ice-free, with warmer waters and lower salinity. Seasonal ice began forming about 7000 years ago and expanded as the climate cooled. These long-term patterns show that continued warming could return the region to mostly ice-free conditions.
Abigail E. Robinson, Anna Scaini, Francisco J. Peña, Peter A. Hambäck, Christoph Humborg, and Fernando Jaramillo
Hydrol. Earth Syst. Sci., 29, 5975–6001, https://doi.org/10.5194/hess-29-5975-2025, https://doi.org/10.5194/hess-29-5975-2025, 2025
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Wetlands provide vital benefits like flood control, drought resilience, and carbon storage, but these depend on how water moves and is stored within the wetland. Using satellite imagery and AI, we mapped water patterns in 43 Swedish wetlands, identifying five hydrological types. This approach reveals differences in flooding and drying, linking wetland water behaviour to the benefits they provide, offering a practical way to understand wetland functions.
Jamie Barnett, Felicity A. Holmes, Joshua Cuzzone, Henning Åkesson, Mathieu Morlighem, Matt O'Regan, Johan Nilsson, Nina Kirchner, and Martin Jakobsson
The Cryosphere, 19, 3631–3653, https://doi.org/10.5194/tc-19-3631-2025, https://doi.org/10.5194/tc-19-3631-2025, 2025
Short summary
Short summary
Understanding how ice sheets have changed in the past can allow us to make better predictions for the future. By running a state-of-the-art model of Ryder Glacier, North Greenland, over the past 12 000 years we find that both a warming atmosphere and the ocean play a key role in the evolution of the glacier. Our conclusions stress that accurately quantifying the ice sheet’s interactions with the ocean is required to predict future changes and reliable sea level rise estimates.
Felicity A. Holmes, Jamie Barnett, Henning Åkesson, Mathieu Morlighem, Johan Nilsson, Nina Kirchner, and Martin Jakobsson
The Cryosphere, 19, 2695–2714, https://doi.org/10.5194/tc-19-2695-2025, https://doi.org/10.5194/tc-19-2695-2025, 2025
Short summary
Short summary
Northern Greenland contains some of the ice sheet's last remaining glaciers with floating ice tongues. One of these is Ryder Glacier, which has been relatively stable in recent decades, in contrast to nearby glaciers. Here, we use a computer model to simulate Ryder Glacier until 2300 under both a low- and a high-emissions scenario. Very high levels of surface melt under a high-emissions future lead to a sea level rise contribution that is an order of magnitude higher than under a low-emissions future.
Flor Vermassen, Clare Bird, Tirza M. Weitkamp, Kate F. Darling, Hanna Farnelid, Céline Heuzé, Allison Y. Hsiang, Salar Karam, Christian Stranne, Marcus Sundbom, and Helen K. Coxall
Biogeosciences, 22, 2261–2286, https://doi.org/10.5194/bg-22-2261-2025, https://doi.org/10.5194/bg-22-2261-2025, 2025
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We provide the first systematic survey of planktonic foraminifera in the high Arctic Ocean. Our results describe the abundance and species composition under summer sea ice. They indicate that the polar specialist N. pachyderma is the only species present, with subpolar species absent. The data set will be a valuable reference for continued monitoring of the state of planktonic foraminifera communities as they respond to the ongoing sea-ice decline and the “Atlantification” of the Arctic Ocean.
Erik Gustafsson, Bo G. Gustafsson, Martijn Hermans, Christoph Humborg, and Christian Stranne
Geosci. Model Dev., 17, 7157–7179, https://doi.org/10.5194/gmd-17-7157-2024, https://doi.org/10.5194/gmd-17-7157-2024, 2024
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Methane (CH4) cycling in the Baltic Proper is studied through model simulations, enabling a first estimate of key CH4 fluxes. A preliminary budget identifies benthic CH4 release as the dominant source and two main sinks: CH4 oxidation in the water (92 % of sinks) and outgassing to the atmosphere (8 % of sinks). This study addresses CH4 emissions from coastal seas and is a first step toward understanding the relative importance of open-water outgassing compared with local coastal hotspots.
Allison P. Lepp, Lauren E. Miller, John B. Anderson, Matt O'Regan, Monica C. M. Winsborrow, James A. Smith, Claus-Dieter Hillenbrand, Julia S. Wellner, Lindsay O. Prothro, and Evgeny A. Podolskiy
The Cryosphere, 18, 2297–2319, https://doi.org/10.5194/tc-18-2297-2024, https://doi.org/10.5194/tc-18-2297-2024, 2024
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Shape and surface texture of silt-sized grains are measured to connect marine sediment records with subglacial water flow. We find that grain shape alteration is greatest in glaciers where high-energy drainage events and abundant melting of surface ice are inferred and that the surfaces of silt-sized sediments preserve evidence of glacial transport. Our results suggest grain shape and texture may reveal whether glaciers previously experienced temperate conditions with more abundant meltwater.
Lara F. Pérez, Paul C. Knutz, John R. Hopper, Marit-Solveig Seidenkrantz, Matt O'Regan, and Stephen Jones
Sci. Dril., 33, 33–46, https://doi.org/10.5194/sd-33-33-2024, https://doi.org/10.5194/sd-33-33-2024, 2024
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The Greenland ice sheet is highly sensitive to global warming and a major contributor to sea level rise. In Northeast Greenland, ice–ocean–tectonic interactions are readily observable today, but geological records that illuminate long-term trends are lacking. NorthGreen aims to promote scientific drilling proposals to resolve key scientific questions on past changes in the Northeast Greenland margin that further affected the broader Earth system.
Julia Muchowski, Martin Jakobsson, Lars Umlauf, Lars Arneborg, Bo Gustafsson, Peter Holtermann, Christoph Humborg, and Christian Stranne
Ocean Sci., 19, 1809–1825, https://doi.org/10.5194/os-19-1809-2023, https://doi.org/10.5194/os-19-1809-2023, 2023
Short summary
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We show observational data of highly increased mixing and vertical salt flux rates in a sparsely sampled region of the northern Baltic Sea. Co-located acoustic observations complement our in situ measurements and visualize turbulent mixing with high spatial resolution. The observed mixing is generally not resolved in numerical models of the area but likely impacts the exchange of water between the adjacent basins as well as nutrient and oxygen conditions in the Bothnian Sea.
Johan Nilsson, Eef van Dongen, Martin Jakobsson, Matt O'Regan, and Christian Stranne
The Cryosphere, 17, 2455–2476, https://doi.org/10.5194/tc-17-2455-2023, https://doi.org/10.5194/tc-17-2455-2023, 2023
Short summary
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We investigate how topographical sills suppress basal glacier melt in Greenlandic fjords. The basal melt drives an exchange flow over the sill, but there is an upper flow limit set by the Atlantic Water features outside the fjord. If this limit is reached, the flow enters a new regime where the melt is suppressed and its sensitivity to the Atlantic Water temperature is reduced.
Gabriel West, Darrell S. Kaufman, Martin Jakobsson, and Matt O'Regan
Geochronology, 5, 285–299, https://doi.org/10.5194/gchron-5-285-2023, https://doi.org/10.5194/gchron-5-285-2023, 2023
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We report aspartic and glutamic acid racemization analyses on Neogloboquadrina pachyderma and Cibicidoides wuellerstorfi from the Arctic Ocean (AO). The rates of racemization in the species are compared. Calibrating the rate of racemization in C. wuellerstorfi for the past 400 ka allows the estimation of sample ages from the central AO. Estimated ages are older than existing age assignments (as previously observed for N. pachyderma), confirming that differences are not due to taxonomic effects.
Jesse R. Farmer, Katherine J. Keller, Robert K. Poirier, Gary S. Dwyer, Morgan F. Schaller, Helen K. Coxall, Matt O'Regan, and Thomas M. Cronin
Clim. Past, 19, 555–578, https://doi.org/10.5194/cp-19-555-2023, https://doi.org/10.5194/cp-19-555-2023, 2023
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Oxygen isotopes are used to date marine sediments via similar large-scale ocean patterns over glacial cycles. However, the Arctic Ocean exhibits a different isotope pattern, creating uncertainty in the timing of past Arctic climate change. We find that the Arctic Ocean experienced large local oxygen isotope changes over glacial cycles. We attribute this to a breakdown of stratification during ice ages that allowed for a unique low isotope value to characterize the ice age Arctic Ocean.
Raisa Alatarvas, Matt O'Regan, and Kari Strand
Clim. Past, 18, 1867–1881, https://doi.org/10.5194/cp-18-1867-2022, https://doi.org/10.5194/cp-18-1867-2022, 2022
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This research contributes to efforts solving research questions related to the history of ice sheet decay in the Northern Hemisphere. The East Siberian continental margin sediments provide ideal material for identifying the mineralogical signature of ice sheet derived material. Heavy mineral analysis from marine glacial sediments from the De Long Trough and Lomonosov Ridge was used in interpreting the activity of the East Siberian Ice Sheet in the Arctic region.
Eva Ehrnsten, Oleg Pavlovitch Savchuk, and Bo Gustav Gustafsson
Biogeosciences, 19, 3337–3367, https://doi.org/10.5194/bg-19-3337-2022, https://doi.org/10.5194/bg-19-3337-2022, 2022
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We studied the effects of benthic fauna, animals living on or in the seafloor, on the biogeochemical cycles of carbon, nitrogen and phosphorus using a model of the Baltic Sea ecosystem. By eating and excreting, the animals transform a large part of organic matter sinking to the seafloor into inorganic forms, which fuel plankton blooms. Simultaneously, when they move around (bioturbate), phosphorus is bound in the sediments. This reduces nitrogen-fixing plankton blooms and oxygen depletion.
Karol Kuliński, Gregor Rehder, Eero Asmala, Alena Bartosova, Jacob Carstensen, Bo Gustafsson, Per O. J. Hall, Christoph Humborg, Tom Jilbert, Klaus Jürgens, H. E. Markus Meier, Bärbel Müller-Karulis, Michael Naumann, Jørgen E. Olesen, Oleg Savchuk, Andreas Schramm, Caroline P. Slomp, Mikhail Sofiev, Anna Sobek, Beata Szymczycha, and Emma Undeman
Earth Syst. Dynam., 13, 633–685, https://doi.org/10.5194/esd-13-633-2022, https://doi.org/10.5194/esd-13-633-2022, 2022
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The paper covers the aspects related to changes in carbon, nitrogen, and phosphorus (C, N, P) external loads; their transformations in the coastal zone; changes in organic matter production (eutrophication) and remineralization (oxygen availability); and the role of sediments in burial and turnover of C, N, and P. Furthermore, this paper also focuses on changes in the marine CO2 system, the structure of the microbial community, and the role of contaminants for biogeochemical processes.
Jaclyn Clement Kinney, Karen M. Assmann, Wieslaw Maslowski, Göran Björk, Martin Jakobsson, Sara Jutterström, Younjoo J. Lee, Robert Osinski, Igor Semiletov, Adam Ulfsbo, Irene Wåhlström, and Leif G. Anderson
Ocean Sci., 18, 29–49, https://doi.org/10.5194/os-18-29-2022, https://doi.org/10.5194/os-18-29-2022, 2022
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We use data crossing Herald Canyon in the Chukchi Sea collected in 2008 and 2014 together with numerical modelling to investigate the circulation in the western Chukchi Sea. A large fraction of water from the Chukchi Sea enters the East Siberian Sea south of Wrangel Island and circulates in an anticyclonic direction around the island. To assess the differences between years, we use numerical modelling results, which show that high-frequency variability dominates the flow in Herald Canyon.
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Short summary
The bottom topography of the Baltic Sea is analysed using the digital depth model from the European Marine Observation and Data Network (EMODnet) published in 2018. Analyses include depth distribution vs. area and seafloor depth variation on a kilometre scale. The limits for the Baltic Sea and analysed sub-basins are from HELCOM. EMODnet is compared with the previously most widely used depth model and the area of deep water exchange between the Bothnian Sea and the Northern Baltic Proper.
The bottom topography of the Baltic Sea is analysed using the digital depth model from the...
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