Articles | Volume 5, issue 1
https://doi.org/10.5194/gchron-5-285-2023
© 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/gchron-5-285-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
19 Jun 2023
Research article |
| 19 Jun 2023
| 19 Jun 2023
Amino acid racemization in Neogloboquadrina pachyderma and Cibicidoides wuellerstorfi from the Arctic Ocean and its implications for age models
Department of Geological Sciences, Stockholm University, Stockholm,
10691, Sweden
Bolin Centre for Climate Research, Stockholm University, Stockholm,
10691, Sweden
Darrell S. Kaufman
School of Earth and Sustainability, Northern Arizona University,
Flagstaff, AZ 86011, USA
Martin Jakobsson
Department of Geological Sciences, Stockholm University, Stockholm,
10691, Sweden
Bolin Centre for Climate Research, Stockholm University, Stockholm,
10691, Sweden
Department of Geological Sciences, Stockholm University, Stockholm,
10691, Sweden
Bolin Centre for Climate Research, Stockholm University, Stockholm,
10691, Sweden
Related authors
Matt O'Regan, Thomas M. Cronin, Brendan Reilly, Aage Kristian Olsen Alstrup, Laura Gemery, Anna Golub, Larry A. Mayer, Mathieu Morlighem, Matthias Moros, Ole L. Munk, Johan Nilsson, Christof Pearce, Henrieka Detlef, Christian Stranne, Flor Vermassen, Gabriel West, and Martin Jakobsson
The Cryosphere, 15, 4073–4097, https://doi.org/10.5194/tc-15-4073-2021, https://doi.org/10.5194/tc-15-4073-2021, 2021
Short summary
Short summary
Ryder Glacier is a marine-terminating glacier in north Greenland discharging ice into the Lincoln Sea. Here we use marine sediment cores to reconstruct its retreat and advance behavior through the Holocene. We show that while Sherard Osborn Fjord has a physiography conducive to glacier and ice tongue stability, Ryder still retreated more than 40 km inland from its current position by the Middle Holocene. This highlights the sensitivity of north Greenland's marine glaciers to climate change.
Francesco Muschitiello, Matt O'Regan, Jannik Martens, Gabriel West, Örjan Gustafsson, and Martin Jakobsson
Geochronology, 2, 81–91, https://doi.org/10.5194/gchron-2-81-2020, https://doi.org/10.5194/gchron-2-81-2020, 2020
Short summary
Short summary
In this study we present a new marine chronology of the last ~30 000 years for a sediment core retrieved from the central Arctic Ocean. Our new chronology reveals substantially faster sedimentation rates during the end of the last glacial cycle, the Last Glacial Maximum, and deglaciation than previously reported, thus implying a substantial re-interpretation of paleoceanographic reconstructions from this sector of the Arctic Ocean.
Gabriel West, Darrell S. Kaufman, Francesco Muschitiello, Matthias Forwick, Jens Matthiessen, Jutta Wollenburg, and Matt O'Regan
Geochronology, 1, 53–67, https://doi.org/10.5194/gchron-1-53-2019, https://doi.org/10.5194/gchron-1-53-2019, 2019
Short summary
Short summary
We report amino acid racemization analyses of foraminifera from well-dated sediment cores from the Yermak Plateau, Arctic Ocean. Sample ages are compared with model predictions, revealing that the rates of racemization generally conform to a global compilation of racemization rates at deep-sea sites. These results highlight the need for further studies to test and explain the origin of the purportedly high rate of racemization indicated by previous analyses of central Arctic sediments.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Laura J. Larocca, James M. Lea, Michael P. Erb, Nicholas P. McKay, Megan Phillips, Kara A. Lamantia, and Darrell S. Kaufman
EGUsphere, https://doi.org/10.5194/egusphere-2024-522, https://doi.org/10.5194/egusphere-2024-522, 2024
Short summary
Short summary
Here we present summer snowline altitude (SLA) timeseries for 269 Arctic glaciers. Between 1984 and 2022, SLAs rose ~150 m, equating to a ~127 m shift per 1 °C of summer warming. SLA is most strongly correlated with annual temperature variables, highlighting their dual effect on ablation and accumulation processes. We show that SLAs are rising fastest on low elevation glaciers, and that >50 % of the studied glaciers may be doomed to disappear by 2100 if the mean rate of SLA rise is maintained.
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
Short summary
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
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Darrell S. Kaufman and Nicholas P. McKay
Clim. Past, 18, 911–917, https://doi.org/10.5194/cp-18-911-2022, https://doi.org/10.5194/cp-18-911-2022, 2022
Short summary
Short summary
Global mean surface temperatures are rising to levels unprecedented in over 100 000 years. This conclusion takes into account both recent global warming and likely future warming, which thereby enables a direct comparison with paleotemperature reconstructions on multi-century timescales.
Lauren J. Davies, Britta J. L. Jensen, and Darrell S. Kaufman
Geochronology, 4, 121–141, https://doi.org/10.5194/gchron-4-121-2022, https://doi.org/10.5194/gchron-4-121-2022, 2022
Short summary
Short summary
Subarctic and Arctic lake sediments provide key data to understand natural climate variability and future climate change. However, they can be difficult to date accurately and of limited use without a robust chronology. We use volcanic ash deposits from the last ~4000 BP to identify anomalously old radiocarbon ages at Cascade Lake, Alaska. A provisional ~15 000-year Bayesian age model is produced for the lake, and a new location for ash from five Late Holocene eruptions is reported.
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
Short summary
Short summary
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.
Henrieka Detlef, Brendan Reilly, Anne Jennings, Mads Mørk Jensen, Matt O'Regan, Marianne Glasius, Jesper Olsen, Martin Jakobsson, and Christof Pearce
The Cryosphere, 15, 4357–4380, https://doi.org/10.5194/tc-15-4357-2021, https://doi.org/10.5194/tc-15-4357-2021, 2021
Short summary
Short summary
Here we examine the Nares Strait sea ice dynamics over the last 7000 years and their implications for the late Holocene readvance of the floating part of Petermann Glacier. We propose that the historically observed sea ice dynamics are a relatively recent feature, while most of the mid-Holocene was marked by variable sea ice conditions in Nares Strait. Nonetheless, major advances of the Petermann ice tongue were preceded by a shift towards harsher sea ice conditions in Nares Strait.
Matt O'Regan, Thomas M. Cronin, Brendan Reilly, Aage Kristian Olsen Alstrup, Laura Gemery, Anna Golub, Larry A. Mayer, Mathieu Morlighem, Matthias Moros, Ole L. Munk, Johan Nilsson, Christof Pearce, Henrieka Detlef, Christian Stranne, Flor Vermassen, Gabriel West, and Martin Jakobsson
The Cryosphere, 15, 4073–4097, https://doi.org/10.5194/tc-15-4073-2021, https://doi.org/10.5194/tc-15-4073-2021, 2021
Short summary
Short summary
Ryder Glacier is a marine-terminating glacier in north Greenland discharging ice into the Lincoln Sea. Here we use marine sediment cores to reconstruct its retreat and advance behavior through the Holocene. We show that while Sherard Osborn Fjord has a physiography conducive to glacier and ice tongue stability, Ryder still retreated more than 40 km inland from its current position by the Middle Holocene. This highlights the sensitivity of north Greenland's marine glaciers to climate change.
Douglas P. Steen, Joseph S. Stoner, Jason P. Briner, and Darrell S. Kaufman
Geochronology Discuss., https://doi.org/10.5194/gchron-2021-19, https://doi.org/10.5194/gchron-2021-19, 2021
Publication in GChron not foreseen
Short summary
Short summary
Paleomagnetic data from Cascade Lake (Brooks Range, Alaska) extend the radiometric-based age model of the sedimentary sequence extending back 21 kyr. Correlated ages based on prominent features in paleomagnetic secular variations (PSV) diverge from the radiometric ages in the upper 1.6 m, by up to about 2000 years at around 4 ka. Four late Holocene cryptotephra in this section support the PSV chronology and suggest the influence of hard water or aged organic material.
Cody C. Routson, Darrell S. Kaufman, Nicholas P. McKay, Michael P. Erb, Stéphanie H. Arcusa, Kendrick J. Brown, Matthew E. Kirby, Jeremiah P. Marsicek, R. Scott Anderson, Gonzalo Jiménez-Moreno, Jessica R. Rodysill, Matthew S. Lachniet, Sherilyn C. Fritz, Joseph R. Bennett, Michelle F. Goman, Sarah E. Metcalfe, Jennifer M. Galloway, Gerrit Schoups, David B. Wahl, Jesse L. Morris, Francisca Staines-Urías, Andria Dawson, Bryan N. Shuman, Daniel G. Gavin, Jeffrey S. Munroe, and Brian F. Cumming
Earth Syst. Sci. Data, 13, 1613–1632, https://doi.org/10.5194/essd-13-1613-2021, https://doi.org/10.5194/essd-13-1613-2021, 2021
Short summary
Short summary
We present a curated database of western North American Holocene paleoclimate records, which have been screened on length, resolution, and geochronology. The database gathers paleoclimate time series that reflect temperature, hydroclimate, or circulation features from terrestrial and marine sites, spanning a region from Mexico to Alaska. This publicly accessible collection will facilitate a broad range of paleoclimate inquiry.
Colin Ware, Larry Mayer, Paul Johnson, Martin Jakobsson, and Vicki Ferrini
Geosci. Instrum. Method. Data Syst., 9, 375–384, https://doi.org/10.5194/gi-9-375-2020, https://doi.org/10.5194/gi-9-375-2020, 2020
Short summary
Short summary
Geographic coordinates (latitude and longitude) are widely used in geospatial applications, and terrains are often defined by regular grids in geographic coordinates. However, because of convergence of lines of longitude near the poles there is oversampling in the latitude (zonal) direction. Also, there is no standard way of defining a hierarchy of grids to consistently deal with data having different spatial resolutions. The proposed global geographic grid system solves both problems.
Chris M. Brierley, Anni Zhao, Sandy P. Harrison, Pascale Braconnot, Charles J. R. Williams, David J. R. Thornalley, Xiaoxu Shi, Jean-Yves Peterschmitt, Rumi Ohgaito, Darrell S. Kaufman, Masa Kageyama, Julia C. Hargreaves, Michael P. Erb, Julien Emile-Geay, Roberta D'Agostino, Deepak Chandan, Matthieu Carré, Partrick J. Bartlein, Weipeng Zheng, Zhongshi Zhang, Qiong Zhang, Hu Yang, Evgeny M. Volodin, Robert A. Tomas, Cody Routson, W. Richard Peltier, Bette Otto-Bliesner, Polina A. Morozova, Nicholas P. McKay, Gerrit Lohmann, Allegra N. Legrande, Chuncheng Guo, Jian Cao, Esther Brady, James D. Annan, and Ayako Abe-Ouchi
Clim. Past, 16, 1847–1872, https://doi.org/10.5194/cp-16-1847-2020, https://doi.org/10.5194/cp-16-1847-2020, 2020
Short summary
Short summary
This paper provides an initial exploration and comparison to climate reconstructions of the new climate model simulations of the mid-Holocene (6000 years ago). These use state-of-the-art models developed for CMIP6 and apply the same experimental set-up. The models capture several key aspects of the climate, but some persistent issues remain.
Bronwen L. Konecky, Nicholas P. McKay, Olga V. Churakova (Sidorova), Laia Comas-Bru, Emilie P. Dassié, Kristine L. DeLong, Georgina M. Falster, Matt J. Fischer, Matthew D. Jones, Lukas Jonkers, Darrell S. Kaufman, Guillaume Leduc, Shreyas R. Managave, Belen Martrat, Thomas Opel, Anais J. Orsi, Judson W. Partin, Hussein R. Sayani, Elizabeth K. Thomas, Diane M. Thompson, Jonathan J. Tyler, Nerilie J. Abram, Alyssa R. Atwood, Olivier Cartapanis, Jessica L. Conroy, Mark A. Curran, Sylvia G. Dee, Michael Deininger, Dmitry V. Divine, Zoltán Kern, Trevor J. Porter, Samantha L. Stevenson, Lucien von Gunten, and Iso2k Project Members
Earth Syst. Sci. Data, 12, 2261–2288, https://doi.org/10.5194/essd-12-2261-2020, https://doi.org/10.5194/essd-12-2261-2020, 2020
Francesco Muschitiello, Matt O'Regan, Jannik Martens, Gabriel West, Örjan Gustafsson, and Martin Jakobsson
Geochronology, 2, 81–91, https://doi.org/10.5194/gchron-2-81-2020, https://doi.org/10.5194/gchron-2-81-2020, 2020
Short summary
Short summary
In this study we present a new marine chronology of the last ~30 000 years for a sediment core retrieved from the central Arctic Ocean. Our new chronology reveals substantially faster sedimentation rates during the end of the last glacial cycle, the Last Glacial Maximum, and deglaciation than previously reported, thus implying a substantial re-interpretation of paleoceanographic reconstructions from this sector of the Arctic Ocean.
Paul D. Zander, Sönke Szidat, Darrell S. Kaufman, Maurycy Żarczyński, Anna I. Poraj-Górska, Petra Boltshauser-Kaltenrieder, and Martin Grosjean
Geochronology, 2, 63–79, https://doi.org/10.5194/gchron-2-63-2020, https://doi.org/10.5194/gchron-2-63-2020, 2020
Short summary
Short summary
Recent technological advances allow researchers to obtain radiocarbon ages from smaller samples than previously possible. We investigate the reliability and precision of radiocarbon ages obtained from miniature (11–150 μg C) samples of terrestrial plant fragments taken from sediment cores from Lake Żabińskie, Poland. We further investigate how sampling density (the number of ages per 1000 years) and sample mass (which is related to age precision) influence the performance of age–depth models.
Zhongshi Zhang, Qing Yan, Ran Zhang, Florence Colleoni, Gilles Ramstein, Gaowen Dai, Martin Jakobsson, Matt O'Regan, Stefan Liess, Denis-Didier Rousseau, Naiqing Wu, Elizabeth J. Farmer, Camille Contoux, Chuncheng Guo, Ning Tan, and Zhengtang Guo
Clim. Past Discuss., https://doi.org/10.5194/cp-2020-38, https://doi.org/10.5194/cp-2020-38, 2020
Manuscript not accepted for further review
Short summary
Short summary
Whether an ice sheet once grew over Northeast Siberia-Beringia has been debated for decades. By comparing climate modelling with paleoclimate and glacial records from around the North Pacific, this study shows that the Laurentide-Eurasia-only ice sheet configuration fails in explaining these records, while a scenario involving the ice sheet over Northeast Siberia-Beringia succeeds. It highlights the complexity in glacial climates and urges new investigations across Northeast Siberia-Beringia.
Kelly A. Hogan, Martin Jakobsson, Larry Mayer, Brendan T. Reilly, Anne E. Jennings, Joseph S. Stoner, Tove Nielsen, Katrine J. Andresen, Egon Nørmark, Katrien A. Heirman, Elina Kamla, Kevin Jerram, Christian Stranne, and Alan Mix
The Cryosphere, 14, 261–286, https://doi.org/10.5194/tc-14-261-2020, https://doi.org/10.5194/tc-14-261-2020, 2020
Short summary
Short summary
Glacial sediments in fjords hold a key record of environmental and ice dynamic changes during ice retreat. Here we use a comprehensive geophysical survey from the Petermann Fjord system in NW Greenland to map these sediments, identify depositional processes and calculate glacial erosion rates for the retreating palaeo-Petermann ice stream. Ice streaming is the dominant control on glacial erosion rates which vary by an order of magnitude during deglaciation and are in line with modern rates.
Martin Jakobsson, Matt O'Regan, Carl-Magnus Mörth, Christian Stranne, Elizabeth Weidner, Jim Hansson, Richard Gyllencreutz, Christoph Humborg, Tina Elfwing, Alf Norkko, Joanna Norkko, Björn Nilsson, and Arne Sjöström
Earth Surf. Dynam., 8, 1–15, https://doi.org/10.5194/esurf-8-1-2020, https://doi.org/10.5194/esurf-8-1-2020, 2020
Short summary
Short summary
We studied coastal sea floor terraces in parts of the Baltic Sea using various types of sonar data, sediment cores, and video. Terraces (~1 m high, > 100 m long) are widespread in depths < 15 m and are formed in glacial clay. Our study supports an origin from groundwater flow through silty layers, undermining overlying layers when discharged at the sea floor. Submarine groundwater discharge like this may be a significant source of freshwater to the Baltic Sea that needs to be studied further.
Ellie Broadman, Lorna L. Thurston, Erik Schiefer, Nicholas P. McKay, David Fortin, Jason Geck, Michael G. Loso, Matt Nolan, Stéphanie H. Arcusa, Christopher W. Benson, Rebecca A. Ellerbroek, Michael P. Erb, Cody C. Routson, Charlotte Wiman, A. Jade Wong, and Darrell S. Kaufman
Earth Syst. Sci. Data, 11, 1957–1970, https://doi.org/10.5194/essd-11-1957-2019, https://doi.org/10.5194/essd-11-1957-2019, 2019
Short summary
Short summary
Rapid climate warming is impacting physical processes in Arctic environments. Glacier–fed lakes are influenced by many of these processes, and they are impacted by the changing behavior of weather, glaciers, and rivers. We present data from weather stations, river gauging stations, lake moorings, and more, following 4 years of environmental monitoring in the watershed of Lake Peters, a glacier–fed lake in Arctic Alaska. These data can help us study the changing dynamics of this remote setting.
Gabriel West, Darrell S. Kaufman, Francesco Muschitiello, Matthias Forwick, Jens Matthiessen, Jutta Wollenburg, and Matt O'Regan
Geochronology, 1, 53–67, https://doi.org/10.5194/gchron-1-53-2019, https://doi.org/10.5194/gchron-1-53-2019, 2019
Short summary
Short summary
We report amino acid racemization analyses of foraminifera from well-dated sediment cores from the Yermak Plateau, Arctic Ocean. Sample ages are compared with model predictions, revealing that the rates of racemization generally conform to a global compilation of racemization rates at deep-sea sites. These results highlight the need for further studies to test and explain the origin of the purportedly high rate of racemization indicated by previous analyses of central Arctic sediments.
Christian Stranne, Matt O'Regan, Martin Jakobsson, Volker Brüchert, and Marcelo Ketzer
Solid Earth, 10, 1541–1554, https://doi.org/10.5194/se-10-1541-2019, https://doi.org/10.5194/se-10-1541-2019, 2019
Martin Jakobsson, Christian Stranne, Matt O'Regan, Sarah L. Greenwood, Bo Gustafsson, Christoph Humborg, and Elizabeth Weidner
Ocean Sci., 15, 905–924, https://doi.org/10.5194/os-15-905-2019, https://doi.org/10.5194/os-15-905-2019, 2019
Short summary
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.
Chris S. M. Turney, Helen V. McGregor, Pierre Francus, Nerilie Abram, Michael N. Evans, Hugues Goosse, Lucien von Gunten, Darrell Kaufman, Hans Linderholm, Marie-France Loutre, and Raphael Neukom
Clim. Past, 15, 611–615, https://doi.org/10.5194/cp-15-611-2019, https://doi.org/10.5194/cp-15-611-2019, 2019
Short summary
Short summary
This PAGES (Past Global Changes) 2k (climate of the past 2000 years working group) special issue of Climate of the Past brings together the latest understanding of regional change and impacts from PAGES 2k groups across a range of proxies and regions. The special issue has emerged from a need to determine the magnitude and rate of change of regional and global climate beyond the timescales accessible within the observational record.
Birgit Wild, Natalia Shakhova, Oleg Dudarev, Alexey Ruban, Denis Kosmach, Vladimir Tumskoy, Tommaso Tesi, Hanna Joß, Helena Alexanderson, Martin Jakobsson, Alexey Mazurov, Igor Semiletov, and Örjan Gustafsson
The Cryosphere Discuss., https://doi.org/10.5194/tc-2018-229, https://doi.org/10.5194/tc-2018-229, 2018
Revised manuscript not accepted
Short summary
Short summary
The thaw and degradation of subsea permafrost on the Arctic Ocean shelves is one of the key uncertainties concerning natural greenhouse gas emissions since difficult access limits the availability of observational data. In this study, we describe sediment properties and age constraints of a unique set of three subsea permafrost cores from the East Siberian Arctic Shelf, as well as content, origin and degradation state of organic matter at the current thaw front.
Richard H. Levy, Gavin B. Dunbar, Marcus J. Vandergoes, Jamie D. Howarth, Tony Kingan, Alex R. Pyne, Grant Brotherston, Michael Clarke, Bob Dagg, Matthew Hill, Evan Kenton, Steve Little, Darcy Mandeno, Chris Moy, Philip Muldoon, Patrick Doyle, Conrad Raines, Peter Rutland, Delia Strong, Marianna Terezow, Leise Cochrane, Remo Cossu, Sean Fitzsimons, Fabio Florindo, Alexander L. Forrest, Andrew R. Gorman, Darrell S. Kaufman, Min Kyung Lee, Xun Li, Pontus Lurcock, Nicholas McKay, Faye Nelson, Jennifer Purdie, Heidi A. Roop, S. Geoffrey Schladow, Abha Sood, Phaedra Upton, Sharon L. Walker, and Gary S. Wilson
Sci. Dril., 24, 41–50, https://doi.org/10.5194/sd-24-41-2018, https://doi.org/10.5194/sd-24-41-2018, 2018
Short summary
Short summary
A new annually resolvable sedimentary record of southern hemisphere climate has been recovered from Lake Ohau, South Island, New Zealand. The Lake Ohau Climate History (LOCH) Project acquired cores from two sites that preserve an 80 m thick sequence of laminated mud that accumulated since the lake formed ~ 17 000 years ago. Cores were recovered using a purpose-built barge and drilling system designed to recover soft sediment from relatively thick sedimentary sequences at water depths up to 100 m.
Zhongshi Zhang, Qing Yan, Elizabeth J. Farmer, Camille Li, Gilles Ramstein, Terence Hughes, Martin Jakobsson, Matt O'Regan, Ran Zhang, Ning Tan, Camille Contoux, Christophe Dumas, and Chuncheng Guo
Clim. Past Discuss., https://doi.org/10.5194/cp-2018-79, https://doi.org/10.5194/cp-2018-79, 2018
Revised manuscript not accepted
Short summary
Short summary
Our study challenges the widely accepted idea that the Laurentide-Eurasian ice sheets gradually extended across North America and Northwest Eurasia, and suggests the growth of the NH ice sheets is much more complicated. We find climate feedbacks regulate the distribution of the NH ice sheets, producing swings between two distinct ice sheet configurations: the Laurentide-Eurasian and a circum-Arctic configuration, where large ice sheets existed over Northeast Siberia and the Canadian Rockies.
Christian Stranne, Larry Mayer, Martin Jakobsson, Elizabeth Weidner, Kevin Jerram, Thomas C. Weber, Leif G. Anderson, Johan Nilsson, Göran Björk, and Katarina Gårdfeldt
Ocean Sci., 14, 503–514, https://doi.org/10.5194/os-14-503-2018, https://doi.org/10.5194/os-14-503-2018, 2018
Short summary
Short summary
The ocean surface mixed layer depth (MLD) is an important parameter within several research disciplines, as variations in the MLD influence air–sea CO2 exchange and ocean primary production. A new method is presented in which acoustic mapping of the MLD is done remotely by means of echo sounders. This method allows for observations of high-frequency variability in the MLD, as horizontal and temporal resolutions can be increased by orders of magnitude compared to traditional in situ measurements.
Bryan N. Shuman, Cody Routson, Nicholas McKay, Sherilyn Fritz, Darrell Kaufman, Matthew E. Kirby, Connor Nolan, Gregory T. Pederson, and Jeannine-Marie St-Jacques
Clim. Past, 14, 665–686, https://doi.org/10.5194/cp-14-665-2018, https://doi.org/10.5194/cp-14-665-2018, 2018
Short summary
Short summary
A synthesis of 93 published records reveals that moisture availability increased over large portions of North America over the past 2000 years, the Common Era (CE). In many records, the second millennium CE tended to be wetter than the first millennium CE. The long-term changes formed the background for annual to multi-decade variations, such as "mega-droughts", and also provide a context for amplified rates of hydrologic change today.
Darrell S. Kaufman and PAGES 2k special-issue editorial team
Clim. Past, 14, 593–600, https://doi.org/10.5194/cp-14-593-2018, https://doi.org/10.5194/cp-14-593-2018, 2018
Short summary
Short summary
We explain the procedure used to attain a high and consistent level of data stewardship across a special issue of the journal Climate of the Past. We discuss the challenges related to (1) determining which data are essential for public archival, (2) using data generated by others, and (3) understanding data citations. We anticipate that open-data sharing in paleo sciences will accelerate as the advantages become more evident and as practices that reduce data loss become the accepted convention.
Göran Björk, Martin Jakobsson, Karen Assmann, Leif G. Andersson, Johan Nilsson, Christian Stranne, and Larry Mayer
Ocean Sci., 14, 1–13, https://doi.org/10.5194/os-14-1-2018, https://doi.org/10.5194/os-14-1-2018, 2018
Short summary
Short summary
This study presents detailed bathymetric data along with hydrographic data at two deep passages across the Lomonosov Ridge in the Arctic Ocean. The southern channel is relatively smooth with a sill depth close to 1700 m. Hydrographic data reveals an eastward flow in the southern part and opposite in the northern part. The northern passage is characterized by a narrow and steep ridge with a sill depth of 1470 m. Here, water exchange appears to occur in well-defined but irregular vertical layers.
Laura Gemery, Thomas M. Cronin, Robert K. Poirier, Christof Pearce, Natalia Barrientos, Matt O'Regan, Carina Johansson, Andrey Koshurnikov, and Martin Jakobsson
Clim. Past, 13, 1473–1489, https://doi.org/10.5194/cp-13-1473-2017, https://doi.org/10.5194/cp-13-1473-2017, 2017
Short summary
Short summary
Continuous, highly abundant and well-preserved fossil ostracodes were studied from radiocarbon-dated sediment cores collected on the Lomonosov Ridge (Arctic Ocean) that indicate varying oceanographic conditions during the last ~50 kyr. Ostracode assemblages from cores taken during the SWERUS-C3 2014 Expedition, Leg 2, reflect paleoenvironmental changes during glacial, deglacial, and interglacial transitions, including changes in sea-ice cover and Atlantic Water inflow into the Eurasian Basin.
Matt O'Regan, Jan Backman, Natalia Barrientos, Thomas M. Cronin, Laura Gemery, Nina Kirchner, Larry A. Mayer, Johan Nilsson, Riko Noormets, Christof Pearce, Igor Semiletov, Christian Stranne, and Martin Jakobsson
Clim. Past, 13, 1269–1284, https://doi.org/10.5194/cp-13-1269-2017, https://doi.org/10.5194/cp-13-1269-2017, 2017
Short summary
Short summary
Past glacial activity on the East Siberian continental margin is poorly known, partly due to the lack of geomorphological evidence. Here we present geophysical mapping and sediment coring data from the East Siberian shelf and slope revealing the presence of a glacially excavated cross-shelf trough reaching to the continental shelf edge north of the De Long Islands. The data provide direct evidence for extensive glacial activity on the Siberian shelf that predates the Last Glacial Maximum.
Thomas M. Cronin, Matt O'Regan, Christof Pearce, Laura Gemery, Michael Toomey, Igor Semiletov, and Martin Jakobsson
Clim. Past, 13, 1097–1110, https://doi.org/10.5194/cp-13-1097-2017, https://doi.org/10.5194/cp-13-1097-2017, 2017
Short summary
Short summary
Global sea level rise during the last deglacial flooded the Siberian continental shelf in the Arctic Ocean. Sediment cores, radiocarbon dating, and microfossils show that the regional sea level in the Arctic rose rapidly from about 12 500 to 10 700 years ago. Regional sea level history on the Siberian shelf differs from the global deglacial sea level rise perhaps due to regional vertical adjustment resulting from the growth and decay of ice sheets.
Martin Jakobsson, Christof Pearce, Thomas M. Cronin, Jan Backman, Leif G. Anderson, Natalia Barrientos, Göran Björk, Helen Coxall, Agatha de Boer, Larry A. Mayer, Carl-Magnus Mörth, Johan Nilsson, Jayne E. Rattray, Christian Stranne, Igor Semiletov, and Matt O'Regan
Clim. Past, 13, 991–1005, https://doi.org/10.5194/cp-13-991-2017, https://doi.org/10.5194/cp-13-991-2017, 2017
Short summary
Short summary
The Arctic and Pacific oceans are connected by the presently ~53 m deep Bering Strait. During the last glacial period when the sea level was lower than today, the Bering Strait was exposed. Humans and animals could then migrate between Asia and North America across the formed land bridge. From analyses of sediment cores and geophysical mapping data from Herald Canyon north of the Bering Strait, we show that the land bridge was flooded about 11 000 years ago.
Johan Nilsson, Martin Jakobsson, Chris Borstad, Nina Kirchner, Göran Björk, Raymond T. Pierrehumbert, and Christian Stranne
The Cryosphere, 11, 1745–1765, https://doi.org/10.5194/tc-11-1745-2017, https://doi.org/10.5194/tc-11-1745-2017, 2017
Short summary
Short summary
Recent data suggest that a 1 km thick ice shelf extended over the glacial Arctic Ocean during MIS 6, about 140 000 years ago. Here, we theoretically analyse the development and equilibrium features of such an ice shelf. The ice shelf was effectively dammed by the Fram Strait and the mean ice-shelf thickness was controlled primarily by the horizontally integrated mass balance. Our results can aid in resolving some outstanding questions of the state of the glacial Arctic Ocean.
Clint M. Miller, Gerald R. Dickens, Martin Jakobsson, Carina Johansson, Andrey Koshurnikov, Matt O'Regan, Francesco Muschitiello, Christian Stranne, and Carl-Magnus Mörth
Biogeosciences, 14, 2929–2953, https://doi.org/10.5194/bg-14-2929-2017, https://doi.org/10.5194/bg-14-2929-2017, 2017
Short summary
Short summary
Continental slopes north of the East Siberian Sea are assumed to hold large amounts of methane. We present pore water chemistry from the 2014 SWERUS-C3 expedition. These are among the first results generated from this vast climatically sensitive region, and they imply that abundant methane, including gas hydrates, do not characterize the East Siberian Sea slope or rise. This contradicts previous modeling and discussions, which due to the lack of data are almost entirely based assumption.
Leif G. Anderson, Göran Björk, Ola Holby, Sara Jutterström, Carl Magnus Mörth, Matt O'Regan, Christof Pearce, Igor Semiletov, Christian Stranne, Tim Stöven, Toste Tanhua, Adam Ulfsbo, and Martin Jakobsson
Ocean Sci., 13, 349–363, https://doi.org/10.5194/os-13-349-2017, https://doi.org/10.5194/os-13-349-2017, 2017
Short summary
Short summary
We use data collected in 2014 to show that the outflow of nutrient-rich water occurs much further to the west than has been reported in the past. We suggest that this is due to much less summer sea-ice coverage in the northwestern East Siberian Sea than in the past decades. Further, our data support a more complicated flow pattern in the region where the Mendeleev Ridge reaches the shelf compared to the general cyclonic circulation within the individual basins as suggested historically.
Christof Pearce, Aron Varhelyi, Stefan Wastegård, Francesco Muschitiello, Natalia Barrientos, Matt O'Regan, Thomas M. Cronin, Laura Gemery, Igor Semiletov, Jan Backman, and Martin Jakobsson
Clim. Past, 13, 303–316, https://doi.org/10.5194/cp-13-303-2017, https://doi.org/10.5194/cp-13-303-2017, 2017
Short summary
Short summary
The eruption of the Alaskan Aniakchak volcano of 3.6 thousand years ago was one of the largest Holocene eruptions worldwide. The resulting ash is found in several Alaskan sites and as far as Newfoundland and Greenland. In this study, we found ash from the Aniakchak eruption in a marine sediment core from the western Chukchi Sea in the Arctic Ocean. Combined with radiocarbon dates on mollusks, the volcanic age marker is used to calculate the marine radiocarbon reservoir age at that time.
H. S. Sundqvist, D. S. Kaufman, N. P. McKay, N. L. Balascio, J. P. Briner, L. C. Cwynar, H. P. Sejrup, H. Seppä, D. A. Subetto, J. T. Andrews, Y. Axford, J. Bakke, H. J. B. Birks, S. J. Brooks, A. de Vernal, A. E. Jennings, F. C. Ljungqvist, K. M. Rühland, C. Saenger, J. P. Smol, and A. E. Viau
Clim. Past, 10, 1605–1631, https://doi.org/10.5194/cp-10-1605-2014, https://doi.org/10.5194/cp-10-1605-2014, 2014
F. O. Nitsche, K. Gohl, R. D. Larter, C.-D. Hillenbrand, G. Kuhn, J. A. Smith, S. Jacobs, J. B. Anderson, and M. Jakobsson
The Cryosphere, 7, 249–262, https://doi.org/10.5194/tc-7-249-2013, https://doi.org/10.5194/tc-7-249-2013, 2013
Related subject area
Amino acid racemization
A new method for amino acid geochronology of the bivalve shell Arctica islandica
Amino acid racemization in Quaternary foraminifera from the Yermak Plateau, Arctic Ocean
Martina L. G. Conti, Paul G. Butler, David J. Reynolds, Tamara Trofimova, James D. Scourse, and Kirsty E. H. Penkman
EGUsphere, https://doi.org/10.5194/egusphere-2023-2560, https://doi.org/10.5194/egusphere-2023-2560, 2023
Short summary
Short summary
The mollusc Arctica islandica can survive for hundreds of years and its annual growth captures environmental conditions, so each shell provides a detailed climatic record. Dating is essential for sample selection, but radiocarbon and crossdating are time-consuming and costly. As an alternative, amino acid geochronology was investigated in the three aragonitic layers forming the shells. This study confirms the value of AAG as a method for rangefinder dating Quaternary A. islandica shells.
Gabriel West, Darrell S. Kaufman, Francesco Muschitiello, Matthias Forwick, Jens Matthiessen, Jutta Wollenburg, and Matt O'Regan
Geochronology, 1, 53–67, https://doi.org/10.5194/gchron-1-53-2019, https://doi.org/10.5194/gchron-1-53-2019, 2019
Short summary
Short summary
We report amino acid racemization analyses of foraminifera from well-dated sediment cores from the Yermak Plateau, Arctic Ocean. Sample ages are compared with model predictions, revealing that the rates of racemization generally conform to a global compilation of racemization rates at deep-sea sites. These results highlight the need for further studies to test and explain the origin of the purportedly high rate of racemization indicated by previous analyses of central Arctic sediments.
Cited articles
Alexanderson, H., Backman, J., Cronin, T. M., Funder, S., Ingólfsson,
Ó., Jakobsson, M., Landvik, J. Y., Löwemark, L., Mangerud, J.,
März, C., Möller, P., O'Regan, M., and Spielhagen, R. F.: An Arctic
perspective on dating Mid-Late Pleistocene environmental history, Quaternary Sci.
Rev., 92, 9–31, https://doi.org/10.1016/j.quascirev.2013.09.023, 2014.
Anthonissen, D. E. and Ogg, J. G.: Cenozoic and Cretaceous Biochronology of
Planktonic Foraminifera and Calcareous Nannofossils, in: The Geologic Time
Scale, edited by: Gradstein, F. M., Ogg, J. G., Schmitz, M., and Ogg, G., Elsevier, 1083–1127,
https://doi.org/10.1016/B978-0-444-59425-9.15003-6, 2012.
Backman, J., Jakobsson, M., Lvlie, R., Polyak, L., and Febo, L. A.: Is the
central Arctic Ocean a sediment starved basin?, Quaternary Sci. Rev., 20, 1435–1454, https://doi.org/10.1016/j.quascirev.2003.12.005, 2004.
Backman, J., Jakobsson, M., Frank, M., Sangiorgi, F., Brinkhuis, H.,
Stickley, C., O'Regan, M., Løvlie, R., Pälike, H., Spofforth, D.,
Gattacecca, J., Moran, K., King, J., and Heil, C.: Age model and
core-seismic integration for the Cenozoic Arctic Coring Expedition sediments
from the Lomonosov Ridge, Paleoceanography, 23, PA1S01,
https://doi.org/10.1029/2007PA001476, 2008.
Bauch, H. A.: Sedimentation rate of sediment core PS1906-2, PANGAEA,
https://doi.org/10.1594/PANGAEA.82396, 2002.
Bauch, H. A.: Interglacial climates and the Atlantic meridional overturning
circulation: is there an Arctic controversy?, Quaternary Sci. Rev., 63, 1–22,
https://doi.org/10.1016/j.quascirev.2012.11.023, 2013.
Boggild, K., Mosher, D. C., Travaglini, P., Gebhardt, C., and Mayer, L.:
Mass wasting on Alpha Ridge in the Arctic Ocean: new insights from multibeam
bathymetry and sub-bottom profiler data, Geol. Soc. Lond. Spec. Publ., 500,
323–340, https://doi.org/10.1144/SP500-2019-196, 2020.
Braun, S., Mhatre, S. S., Jaussi, M., Røy, H., Kjeldsen, K. U., Pearce,
C., Seidenkrantz, M.-S., Jørgensen, B. B., and Lomstein, B. Aa.:
Microbial turnover times in the deep seabed studied by amino acid
racemization modelling, Sci. Rep., 7, 5680,
https://doi.org/10.1038/s41598-017-05972-z, 2017.
Burkett, A. M., Rathburn, A. E., Elena Pérez, M., Levin, L. A., and
Martin, J. B.: Colonization of over a thousand Cibicidoides wuellerstorfi (foraminifera: Schwager,
1866) on artificial substrates in seep and adjacent off-seep locations in
dysoxic, deep-sea environments, Deep-Sea Res. Pt. I, 117,
39–50, https://doi.org/10.1016/j.dsr.2016.08.011, 2016.
Clarke, S. J. and Murray-Wallace, C. V.: Mathematical expressions used in
amino acid racemisation geochronology – a review, Quat. Geochronol., 1,
261–278, https://doi.org/10.1016/j.quageo.2006.12.002, 2006.
Cronin, T. M., Dwyer, G. S., Farmer, J., Bauch, H. A., Spielhagen, R. F.,
Jakobsson, M., Nilsson, J., Briggs, W. M., and Stepanova, A.: Deep Arctic
Ocean warming during the last glacial cycle, Nat. Geosci., 5, 631–634,
https://doi.org/10.1038/ngeo1557, 2012.
Cronin, T. M., Keller, K. J., Farmer, J. R., Schaller, M. F., O'Regan, M.,
Poirier, R., Coxall, H., Dwyer, G. S., Bauch, H., Kindstedt, I. G.,
Jakobsson, M., Marzen, R., and Santin, E.: Interglacial paleoclimate in the
Arctic, Paleoceanography, 34, 1959–1979,
https://doi.org/10.1029/2019PA003708, 2019.
Darling, K. F., Wade, C. M., Siccha, M., Trommer, G., Schulz, H.,
Abdolalipour, S., and Kurasawa, A.: Genetic diversity and ecology of the
planktonic foraminifers Globigerina bulloides, Turborotalita quinqueloba and Neogloboquadrina pachyderma off the Oman margin during the late SW
Monsoon, Mar. Micropaleontol., 137, 64–77,
https://doi.org/10.1016/j.marmicro.2017.10.006, 2017.
Frank, M., Backman, J., Jakobsson, M., Moran, K., O'Regan, M., King, J.,
Haley, B. A., Kubik, P. W., and Garbe-Schönberg, D.: Beryllium isotopes
in central Arctic Ocean sediments over the past 12.3 million years:
Stratigraphic and paleoclimatic implications, Paleoceanography,
23, PA1S02, https://doi.org/10.1029/2007PA001478, 2008.
Hanslik, D., Löwemark, L., and Jakobsson, M.: Biogenic and detrital-rich
intervals in central Arctic Ocean cores identified using X-ray fluorescence
scanning, Polar Res., 32, 18386,
https://doi.org/10.3402/polar.v32i0.18386, 2013.
Haugen, J.-E., Sejrup, H. P., and Vogt, N. B.: Chemotaxonomy of Quaternary
benthic foraminifera using amino acids, J. Foramin. Res., 19, 38–51,
https://doi.org/10.2113/gsjfr.19.1.38, 1989.
Hillaire-Marcel, C., Ghaleb, B., de Vernal, A., Maccali, J., Cuny, K.,
Jacobel, A., Le Duc, C., and McManus, J.: A new chronology of late
quaternary sequences from the central Arctic Ocean based on “extinction
ages” of their excesses in 231Pa and 230Th, Geochem. Geophy.
Geosy., 18, 4573–4585, https://doi.org/10.1002/2017GC007050, 2017.
Jakobsson, M. and O'Regan, M.: Deep iceberg ploughmarks in the central
Arctic Ocean, Geol. Soc. Lond. Mem., 46, 287–288,
https://doi.org/10.1144/M46.14, 2016.
Jakobsson, M., Løvlie, R., Arnold, E. M., Backman, J., Polyak, L.,
Knutsen, J. O., and Musatov, E.: Pleistocene stratigraphy and
paleoenvironmental variation from Lomonosov Ridge sediments, central Arctic
Ocean. Global Planet. Change, 31, 1–22,
https://doi.org/10.1016/S0921-8181(01)00110-2, 2001.
Jakobsson, M., Backman, J., Murray, A., and Løvlie, R.: Optically
stimulated luminescence dating supports central Arctic Ocean cm-scale
sedimentation rates, Geochem. Geophy. Geosy., 4, 1016,
https://doi.org/10.1029/2002GC000423, 2003.
Jakobsson, M., Andreassen, K., Bjarnadóttir, L. R., Dove, D.,
Dowdeswell, J. A., England, J. H., Funder, S., Hogan, K., Ingólfsson,
Ó., Jennings, A., Krog Larsen, N., Kirchner, N., Landvik, J. Y., Mayer,
L., Mikkelsen, N., Möller, P., Niessen, F., Nilsson, J., O'Regan, M.,
Polyak, L., Nørgaard-Pedersen, N., and Stein, R.: Arctic Ocean glacial
history, Quaternary Sci. Rev., 92, 40–67,
https://doi.org/10.1016/j.quascirev.2013.07.033, 2014.
Jakobsson, M., Mayer, L. A., Bringensparr, C., Castro, C. F., Mohammad, R.,
Johnson, P., Ketter, T., Accettella, D., Amblas, D., An, L., Arndt, J. E.,
Canals, M., Casamor, J. L., Chauché, N., Coakley, B., Danielson, S.,
Demarte, M., Dickson, M.-L., Dorschel, B., Dowdeswell, J. A., Dreutter, S.,
Fremand, A. C., Gallant, D., Hall, J. K., Hehemann, L., Hodnesdal, H., Hong,
J., Ivaldi, R., Kane, E., Klaucke, I., Krawczyk, D. W., Kristoffersen, Y.,
Kuipers, B. R., Millan, R., Masetti, G., Morlighem, M., Noormets, R.,
Prescott, M. M., Rebesco, M., Rignot, E., Semiletov, I., Tate, A. J.,
Travaglini, P., Velicogna, I., Weatherall, P., Weinrebe, W., Willis, J. K.,
Wood, M., Zarayskaya, Y., Zhang, T., Zimmermann, M., and Zinglersen, K. B.:
The International Bathymetric Chart of the Arctic Ocean Version 4.0, Sci.
Data, 7, 176, https://doi.org/10.1038/s41597-020-0520-9, 2020.
Jansen, E., Fronval, T., Rack, F., and Channell, J. E. T.: IRD tuned age
model of ODP Site 151-907, PANGAEA, https://doi.org/10.1594/PANGAEA.848080, 2000a.
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,
https://doi.org/10.1029/1999PA000435, 2000b.
Kaufman, D., Cooper, K., Behl, R., Billups, K., Bright, J., Gardner, K.,
Hearty, P., Jakobsson, M., Mendes, I., O'Leary, M., Polyak, L., Rasmussen,
T., Rosa, F., and Schmidt, M.: Amino acid racemization in mono-specific
foraminifera from Quaternary deep-sea sediments, Quat. Geochronol., 16,
50–61, https://doi.org/10.1016/j.quageo.2012.07.006, 2013.
Kaufman, D. S.: Temperature sensitivity of aspartic and glutamic acid
racemization in the foraminifera Pulleniatina, Quat. Geochronol., 1, 188–207,
https://doi.org/10.1016/j.quageo.2006.06.008, 2006.
Kaufman, D. S. and Manley, W. F.: A new procedure for determining DL amino
acid ratios in fossils using reverse phase liquid chromatography, Quaternary Sci.
Rev., 17, 987–1000, https://doi.org/10.1016/S0277-3791(97)00086-3, 1998.
Kaufman, D. S., Polyak, L., Adler, R., Channell, J. E. T., and Xuan, C.:
Dating late Quaternary planktonic foraminifer Neogloboquadrina pachyderma from the Arctic Ocean using
amino acid racemization, Paleoceanography, 23, PA3224,
https://doi.org/10.1029/2008PA001618, 2008.
King, K. and Neville, C.: Isoleucine epimerization for dating marine
sediments: Importance of analyzing monospecific foraminiferal samples,
Science, 195, 1333–1335, https://doi.org/10.1126/science.195.4284.1333,
1977.
Kosnik, M. A. and Kaufman, D. S.: Identifying outliers and assessing the
accuracy of amino acid racemization measurements for geochronology: II. Data
screening, Quat. Geochronol., 3, 328–341,
https://doi.org/10.1016/j.quageo.2008.04.001, 2008.
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.
Locarnini, R. A., Mishonov, A. V., Baranova, O. K., Boyer, T. P., Zweng, M. M., Garcia, H. E., Reagan, J. R., Seidov, D., Weathers, K. W., Paver, C. R., and Smolyar, I. V.: World Ocean Atlas 2018, Volume 1: Temperature, Mishonov, A. (Technical Editor), NOAA Atlas NESDIS 81, 52 pp., 2018.
Millman E., Wheeler L., Billups K., Kaufman D., and Penkman K. E.: Testing
the effect of oxidizing pre-treatments on amino acids in benthic and
planktic foraminifera tests, Quat. Geochronol., 73, 101401,
https://doi.org/10.1016/j.quageo.2022.101401, 2022.
O'Regan, M., King, J., Backman, J., Jakobsson, M., Pälike, H., Moran,
K., Heil, C., Sakamoto, T., Cronin, T. M., and Jordan, R. W.: Constraints on
the Pleistocene chronology of sediments from the Lomonosov Ridge,
Paleoceanography, 23, PA1S19,
https://doi.org/10.1029/2007PA001551, 2008.
O'Regan, M., John, K. S., Moran, K., Backman, J., King, J., Haley, B. A.,
Jakobsson, M., Frank, M., and Röhl, U.: Plio-Pleistocene trends in ice
rafted debris on the Lomonosov Ridge, Quaternary Int., 219, 168–176,
https://doi.org/10.1016/j.quaint.2009.08.010, 2010.
O'Regan, M., Coxall, H. K., Cronin, T. M., Gyllencreutz, R., Jakobsson, M.,
Kaboth, S., Löwemark, L., Wiers, S., and West, G.: Stratigraphic
occurrences of sub-polar planktic foraminifera in Pleistocene sediments on
the Lomonosov Ridge, Arctic Ocean, Front. Earth Sci., 7, 71,
https://doi.org/10.3389/feart.2019.00071, 2019.
O'Regan, M., Backman, J., Fornaciari, E., Jakobsson, M., and West, G.:
Calcareous nannofossils anchor chronologies for Arctic Ocean sediments back
to 500 ka, Geology, 48, 1115–1119, https://doi.org/10.1130/G47479.1, 2020.
Penkman, K. E., Kaufman, D. S., Maddy, D., and Collins, M. J.: Closed-system
behaviour of the intra-crystalline fraction of amino acids in mollusc
shells, Quat. Geochronol., 3, 2–25,
https://doi.org/10.1016/j.quageo.2007.07.001, 2008.
Pérez, L. F., Jakobsson, M., Funck, T., Andresen, K. J., Nielsen, T.,
O'Regan, M., and Mørk, F.: Late Quaternary sedimentary processes in the
central Arctic Ocean inferred from geophysical mapping, Geomorphology, 369,
107309, https://doi.org/10.1016/j.geomorph.2020.107309, 2020.
Purcell, K., Hillaire-Marcel, C., de Vernal, A., Ghaleb, B., and Stein, R.:
Potential and limitation of 230Th-excess as a chronostratigraphic tool
for late Quaternary Arctic Ocean sediment studies: An example from the
southern Lomonosov Ridge, Mar. Geol., 448, 106802,
https://doi.org/10.1016/j.margeo.2022.106802, 2022.
Raitzsch, M., Rollion-Bard, C., Horn, I., Steinhoefel, G., Benthien, A., Richter, K.-U., Buisson, M., Louvat, P., and Bijma, J.: Technical note: Single-shell δ11B analysis of Cibicidoides wuellerstorfi using femtosecond laser ablation MC-ICPMS and secondary ion mass spectrometry, Biogeosciences, 17, 5365–5375, https://doi.org/10.5194/bg-17-5365-2020, 2020.
Rasmussen, T. L. and Thomsen, E.: Ecology of deep-sea benthic foraminifera
in the North Atlantic during the last glaciation: Food or temperature
control, Palaeogeogr. Palaeocl., 472, 15–32,
https://doi.org/10.1016/j.palaeo.2017.02.012, 2017.
Schlager, U., Jokat, W., Weigelt, E., and Gebhardt, C.: Submarine landslides
along the Siberian termination of the Lomonosov Ridge, Arctic Ocean,
Geomorphology, 382, 107679, https://doi.org/10.1016/j.geomorph.2021.107679,
2021.
Sejrup, H. P. and Haugen, J.-E.: Foraminiferal amino acid stratigraphy of
the Nordic Seas: geological data and pyrolysis experiments, Deep-Sea Res.
Pt. A, 39, S603–S623,
https://doi.org/10.1016/S0198-0149(06)80022-1, 1992.
Sejrup, H. P. and Haugen, J.-E.: Amino acid diagenesis in the marine bivalve
Arctica islandica Linné from northwest European sites: Only time and temperature?, J.
Quaternary Sci., 9, 301–309, https://doi.org/10.1002/jqs.3390090402, 1994.
Sejrup, H. P., Miller, G. H., Brigham-Grette, J., Løvlie, R., and
Hopkins, D.: Amino acid epimerization implies rapid sedimentation rates in
Arctic Ocean cores, Nature, 310, 772–775, https://doi.org/10.1038/310772a0,
1984.
Shackleton, N. J., Sánchez-Goñi, M. F., Pailler, D., and Lancelot,
Y.: Marine Isotope Substage 5e and the Eemian Interglacial, Glob. Planet.
Change, 36, 151–155, https://doi.org/10.1016/S0921-8181(02)00181-9, 2003.
Shephard, G. E., Wiers, S., Bazhenova, E., Pérez, L. F., Mejía, L.
M., Johansson, C., Jakobsson, M., and O'Regan, M.: A North Pole thermal
anomaly? Evidence from new and existing heat flow measurements from the
central Arctic Ocean, J. Geodyn., 118, 166–181,
https://doi.org/10.1016/j.jog.2018.01.017, 2018.
Spielhagen, R. F., Baumann, K. H., Erlenkeuser, H., Nowaczyk, N. R.,
Nørgaard-Pedersen, N., Vogt, C., and Weiel, D.: Arctic Ocean deep-sea
record of northern Eurasian ice sheet history, Quaternary Sci. Rev., 23,
1455–1483, https://doi.org/10.1016/j.quascirev.2003.12.015, 2004.
Thierstein, H. R., Geitzenauer, K. R., Molfino, B., and Shackleton, N. J.:
Global synchroneity of late Quaternary coccolith datum levels validation by
oxygen isotopes, Geology, 5, 400,
https://doi.org/10.1130/0091-7613(1977)5<400:GSOLQC>2.0.CO;2, 1977.
West, G., Kaufman, D. S., Muschitiello, F., Forwick, M., Matthiessen, J., Wollenburg, J., and O'Regan, M.: Amino acid racemization in Quaternary foraminifera from the Yermak Plateau, Arctic Ocean, Geochronology, 1, 53–67, https://doi.org/10.5194/gchron-1-53-2019, 2019.
West, G., Kaufman, D. S., Jakobsson, M., and O'Regan, M.: Quaternary Arctic Ocean Foraminifer Amino Acid Racemization Data, NCEI [data set], https://doi.org/10.25921/bx56-4d69, 2023.
Wheeler L. J., Penkman K. E., Sejrup H. P.: Assessing the intra-crystalline
approach to amino acid geochronology of Neogloboquadrina pachyderma
(sinistral), Quat. Geochronol., 61, 101131,
https://doi.org/10.1016/j.quageo.2020.101131, 2021.
Wollenburg, J. E., Raitzsch, M., and Tiedemann, R.: Novel high-pressure
culture experiments on deep-sea benthic foraminifera – Evidence for
methane seepage-related δ13C of Cibicides wuellerstorfi, Mar. Micropaleontol., 117,
47–64, https://doi.org/10.1016/j.marmicro.2015.04.003, 2015.
Yu, J. and Elderfield, H.: Mg/Ca in the benthic foraminifera Cibicidoides wuellerstorfi and
Cibicidoides mundulus: Temperature versus carbonate ion saturation, Earth Planet. Sc. Lett.,
276, 129–139, https://doi.org/10.1016/j.epsl.2008.09.015, 2008.
Yu, Y., Yang, J., Zheng, L.-Y., Sheng, Q., Li, C.-Y., Wang, M., Zhang,
X.-Y., McMinn, A., Zhang, Y.-Z., Song, X.-Y., and Chen, X.-L.: Diversity of
D-amino acid utilizing bacteria from Kongsfjorden, Arctic and the metabolic
pathways for seven D-amino acids, Front. Microbiol., 10, 2983,
https://doi.org/10.3389/fmicb.2019.02983, 2020.
Short summary
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.
We report aspartic and glutamic acid racemization analyses on Neogloboquadrina pachyderma and...
