Articles | Volume 15, issue 8
https://doi.org/10.5194/essd-15-3351-2023
© 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/essd-15-3351-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Data description paper
| 
02 Aug 2023
Data description paper |
| 02 Aug 2023
| 02 Aug 2023
Ice-core data used for the construction of the Greenland Ice-Core Chronology 2005 and 2021 (GICC05 and GICC21)
Sune Olander Rasmussen
CORRESPONDING AUTHOR
Centre for Ice and Climate, Section for the Physics of Ice, Climate, and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, 2200, Denmark
Dorthe Dahl-Jensen
Centre for Ice and Climate, Section for the Physics of Ice, Climate, and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, 2200, Denmark
Centre for Earth Observation Science, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
Hubertus Fischer
Climate and Environmental Physics, Physics Institute, and Oeschger Center for Climate Change Research, University of Bern, Bern, Switzerland
Katrin Fuhrer
Climate and Environmental Physics, Physics Institute, and Oeschger Center for Climate Change Research, University of Bern, Bern, Switzerland
TOFWERK AG, 3645 Thun, Switzerland
Steffen Bo Hansen
Centre for Ice and Climate, Section for the Physics of Ice, Climate, and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, 2200, Denmark
Margareta Hansson
Department of Physical Geography, University of Stockholm, Stockholm, Sweden
Christine S. Hvidberg
Centre for Ice and Climate, Section for the Physics of Ice, Climate, and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, 2200, Denmark
Ulf Jonsell
Swedish Research Council, Stockholm, 112 21, Sweden
Sepp Kipfstuhl
Alfred Wegener Institute Helmholtz Center for Polar and Marine Science, Bremerhaven, Germany
Urs Ruth
Alfred Wegener Institute Helmholtz Center for Polar and Marine Science, Bremerhaven, Germany
Corporate Research, Robert Bosch GmbH, Stuttgart, 70049, Germany
Jakob Schwander
Climate and Environmental Physics, Physics Institute, and Oeschger Center for Climate Change Research, University of Bern, Bern, Switzerland
Marie-Louise Siggaard-Andersen
Section for Geogenetics, Globe Institute, University of Copenhagen, Copenhagen, Denmark
Giulia Sinnl
Centre for Ice and Climate, Section for the Physics of Ice, Climate, and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, 2200, Denmark
Jørgen Peder Steffensen
Centre for Ice and Climate, Section for the Physics of Ice, Climate, and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, 2200, Denmark
Anders M. Svensson
Centre for Ice and Climate, Section for the Physics of Ice, Climate, and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, 2200, Denmark
Bo M. Vinther
Centre for Ice and Climate, Section for the Physics of Ice, Climate, and Earth, Niels Bohr Institute, University of Copenhagen, Copenhagen, 2200, Denmark
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Naoko Nagatsuka, Kumiko Goto-Azuma, Kana Nagashima, Koji Fujita, Yuki Komuro, Motohiro Hirabayashi, Jun Ogata, Kaori Fukuda, Yoshimi Ogawa-Tsukagawa, Kyotaro Kitamura, Ayaka Yonekura, Fumio Nakazawa, Yukihiko Onuma, Naoyuki Kurita, Sune Olander Rasmussen, Giulia Sinnl, Trevor James Popp, and Dorthe Dahl-Jensen
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Short summary
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We present the first continuous records of dust size, composition, and temporal variations in potential sources from the northeastern Greenland ice core (EGRIP) over the past 100 years. Using a multi-proxy provenance approach based on individual particle analysis, we identify the primary dust sources as the Asian (Gobi) and African (Sahara) deserts. Our findings show shifts in their contributions since the 1970s–1980s, highlighting the effectiveness of this approach during low dust periods.
Florian Painer, Sepp Kipfstuhl, Martyn Drury, Tsutomu Uchida, Johannes Freitag, and Ilka Weikusat
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Margaret Harlan, Helle Astrid Kjær, Aylin de Campo, Anders Svensson, Thomas Blunier, Vasileios Gkinis, Sarah Jackson, Christopher Plummer, and Tessa Vance
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2024-335, https://doi.org/10.5194/essd-2024-335, 2024
Revised manuscript under review for ESSD
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This paper provides high-resolution chemistry and impurity measurements from the Mount Brown South ice core in East Antarctica, from 873 to 2009 CE. Measurements include sodium, ammonium, hydrogen peroxide, electrolytic conductivity, and insoluble microparticles. Data are provided on three scales: 1 mm and 3 cm averaged depth resolution and decadally averaged. The paper also describes the continuous flow analysis systems used to collect the data as well as uncertainties and data quality.
Susanne Preunkert, Pascal Bohleber, Michel Legrand, Adrien Gilbert, Tobias Erhardt, Roland Purtschert, Lars Zipf, Astrid Waldner, Joseph R. McConnell, and Hubertus Fischer
The Cryosphere, 18, 2177–2194, https://doi.org/10.5194/tc-18-2177-2024, https://doi.org/10.5194/tc-18-2177-2024, 2024
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Aslak Grinsted, Nicholas Mossor Rathmann, Ruth Mottram, Anne Munck Solgaard, Joachim Mathiesen, and Christine Schøtt Hvidberg
The Cryosphere, 18, 1947–1957, https://doi.org/10.5194/tc-18-1947-2024, https://doi.org/10.5194/tc-18-1947-2024, 2024
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Ice fracture can cause glacier crevassing and calving. These natural hazards can also modulate the flow and evolution of ice sheets. In a new study, we use a new high-resolution dataset to determine a new failure criterion for glacier ice. Surprisingly, the strength of ice depends on the mode of deformation, and this has potential implications for the currently used flow law of ice.
Johannes Lohmann, Jiamei Lin, Bo M. Vinther, Sune O. Rasmussen, and Anders Svensson
Clim. Past, 20, 313–333, https://doi.org/10.5194/cp-20-313-2024, https://doi.org/10.5194/cp-20-313-2024, 2024
Short summary
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We present the first attempt to constrain the climatic impact of volcanic eruptions with return periods of hundreds of years by the oxygen isotope records of Greenland and Antarctic ice cores covering the last glacial period. A clear multi-annual volcanic cooling signal is seen, but its absolute magnitude is subject to the unknown glacial sensitivity of the proxy. Different proxy signals after eruptions during cooler versus warmer glacial stages may reflect a state-dependent climate response.
Tobias Erhardt, Camilla Marie Jensen, Florian Adolphi, Helle Astrid Kjær, Remi Dallmayr, Birthe Twarloh, Melanie Behrens, Motohiro Hirabayashi, Kaori Fukuda, Jun Ogata, François Burgay, Federico Scoto, Ilaria Crotti, Azzurra Spagnesi, Niccoló Maffezzoli, Delia Segato, Chiara Paleari, Florian Mekhaldi, Raimund Muscheler, Sophie Darfeuil, and Hubertus Fischer
Earth Syst. Sci. Data, 15, 5079–5091, https://doi.org/10.5194/essd-15-5079-2023, https://doi.org/10.5194/essd-15-5079-2023, 2023
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The presented paper provides a 3.8 kyr long dataset of aerosol concentrations from the East Greenland Ice coring Project (EGRIP) ice core. The data consists of 1 mm depth-resolution profiles of calcium, sodium, ammonium, nitrate, and electrolytic conductivity as well as decadal averages of these profiles. Alongside the data a detailed description of the measurement setup as well as a discussion of the uncertainties are given.
Marie Bouchet, Amaëlle Landais, Antoine Grisart, Frédéric Parrenin, Frédéric Prié, Roxanne Jacob, Elise Fourré, Emilie Capron, Dominique Raynaud, Vladimir Ya Lipenkov, Marie-France Loutre, Thomas Extier, Anders Svensson, Etienne Legrain, Patricia Martinerie, Markus Leuenberger, Wei Jiang, Florian Ritterbusch, Zheng-Tian Lu, and Guo-Min Yang
Clim. Past, 19, 2257–2286, https://doi.org/10.5194/cp-19-2257-2023, https://doi.org/10.5194/cp-19-2257-2023, 2023
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A new federative chronology for five deep polar ice cores retrieves 800 000 years of past climate variations with improved accuracy. Precise ice core timescales are key to studying the mechanisms linking changes in the Earth’s orbit to the diverse climatic responses (temperature and atmospheric greenhouse gas concentrations). To construct the chronology, new measurements from the oldest continuous ice core as well as glaciological modeling estimates were combined in a statistical model.
Naoko Nagatsuka, Kumiko Goto-Azuma, Koji Fujita, Yuki Komuro, Motohiro Hirabayashi, Jun Ogata, Kaori Fukuda, Yoshimi Ogawa-Tsukagawa, Kyotaro Kitamura, Ayaka Yonekura, Fumio Nakazawa, Yukihiko Onuma, Naoyuki Kurita, Sune Olander Rasmussen, Giulia Sinnl, Trevor James Popp, and Dorthe Dahl-Jensen
EGUsphere, https://doi.org/10.5194/egusphere-2023-1666, https://doi.org/10.5194/egusphere-2023-1666, 2023
Preprint archived
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We present a new high-temporal-resolution record of mineral composition in a northeastern Greenland ice-core (EGRIP) over the past 100 years. The ice core dust composition and its variation differed significantly from a northwestern Greenland ice core, which is likely due to differences in the geological sources of the dust. Our results suggest that the EGRIP ice core dust was constantly supplied from Northern Eurasia, North America, and Asia with minor contribution from Greenland coast.
Giulia Sinnl, Florian Adolphi, Marcus Christl, Kees C. Welten, Thomas Woodruff, Marc Caffee, Anders Svensson, Raimund Muscheler, and Sune Olander Rasmussen
Clim. Past, 19, 1153–1175, https://doi.org/10.5194/cp-19-1153-2023, https://doi.org/10.5194/cp-19-1153-2023, 2023
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The record of past climate is preserved by several archives from different regions, such as ice cores from Greenland or Antarctica or speleothems from caves such as the Hulu Cave in China. In this study, these archives are aligned by taking advantage of the globally synchronous production of cosmogenic radionuclides. This produces a new perspective on the global climate in the period between 20 000 and 25 000 years ago.
Michaela Mühl, Jochen Schmitt, Barbara Seth, James E. Lee, Jon S. Edwards, Edward J. Brook, Thomas Blunier, and Hubertus Fischer
Clim. Past, 19, 999–1025, https://doi.org/10.5194/cp-19-999-2023, https://doi.org/10.5194/cp-19-999-2023, 2023
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Our ice core measurements show that methane, ethane, and propane concentrations are significantly elevated above their past atmospheric background for Greenland ice samples containing mineral dust. The underlying co-production process happens during the classical discrete wet extraction of air from the ice sample and affects previous reconstructions of the inter-polar difference of methane as well as methane stable isotope records derived from dust-rich Greenland ice.
Nicolas Stoll, Julien Westhoff, Pascal Bohleber, Anders Svensson, Dorthe Dahl-Jensen, Carlo Barbante, and Ilka Weikusat
The Cryosphere, 17, 2021–2043, https://doi.org/10.5194/tc-17-2021-2023, https://doi.org/10.5194/tc-17-2021-2023, 2023
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Impurities in polar ice play a role regarding its climate signal and internal deformation. We bridge different scales using different methods to investigate ice from the Last Glacial Period derived from the EGRIP ice core in Greenland. We characterise different types of cloudy bands, i.e. frequently occurring milky layers in the ice, and analyse their chemistry with Raman spectroscopy and 2D imaging. We derive new insights into impurity localisation and deposition conditions.
Robert Mulvaney, Eric W. Wolff, Mackenzie M. Grieman, Helene H. Hoffmann, Jack D. Humby, Christoph Nehrbass-Ahles, Rachael H. Rhodes, Isobel F. Rowell, Frédéric Parrenin, Loïc Schmidely, Hubertus Fischer, Thomas F. Stocker, Marcus Christl, Raimund Muscheler, Amaelle Landais, and Frédéric Prié
Clim. Past, 19, 851–864, https://doi.org/10.5194/cp-19-851-2023, https://doi.org/10.5194/cp-19-851-2023, 2023
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We present an age scale for a new ice core drilled at Skytrain Ice Rise, an ice rise facing the Ronne Ice Shelf in Antarctica. Various measurements in the ice and air phases are used to match the ice core to other Antarctic cores that have already been dated, and a new age scale is constructed. The 651 m ice core includes ice that is confidently dated to 117 000–126 000 years ago, in the last interglacial. Older ice is found deeper down, but there are flow disturbances in the deeper ice.
Romilly Harris Stuart, Anne-Katrine Faber, Sonja Wahl, Maria Hörhold, Sepp Kipfstuhl, Kristian Vasskog, Melanie Behrens, Alexandra M. Zuhr, and Hans Christian Steen-Larsen
The Cryosphere, 17, 1185–1204, https://doi.org/10.5194/tc-17-1185-2023, https://doi.org/10.5194/tc-17-1185-2023, 2023
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This empirical study uses continuous daily measurements from the Greenland Ice Sheet to document changes in surface snow properties. Consistent changes in snow isotopic composition are observed in the absence of deposition due to surface processes, indicating the isotopic signal of deposited precipitation is not always preserved. Our observations have potential implications for the interpretation of water isotopes in ice cores – historically assumed to reflect isotopic composition at deposition.
Jakob Schwander, Thomas F. Stocker, Remo Walther, and Samuel Marending
The Cryosphere, 17, 1151–1164, https://doi.org/10.5194/tc-17-1151-2023, https://doi.org/10.5194/tc-17-1151-2023, 2023
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RADIX (Rapid Access Drilling and Ice eXtraction) is a fast-access ice-drilling system for prospecting future deep-drilling sites on glaciers and polar ice sheets. It consists of a 40 mm rapid firn drill, a 20 mm deep drill and a logger. The maximum depth range of RADIX is 3100 m by design. The nominal drilling speed is on the order of 40 m h-1. The 15 mm diameter logger provides data on the hole inclination and direction and measures temperature and dust in the ice surrounding the borehole.
Niccolò Maffezzoli, Eliza Cook, Willem G. M. van der Bilt, Eivind N. Støren, Daniela Festi, Florian Muthreich, Alistair W. R. Seddon, François Burgay, Giovanni Baccolo, Amalie R. F. Mygind, Troels Petersen, Andrea Spolaor, Sebastiano Vascon, Marcello Pelillo, Patrizia Ferretti, Rafael S. dos Reis, Jefferson C. Simões, Yuval Ronen, Barbara Delmonte, Marco Viccaro, Jørgen Peder Steffensen, Dorthe Dahl-Jensen, Kerim H. Nisancioglu, and Carlo Barbante
The Cryosphere, 17, 539–565, https://doi.org/10.5194/tc-17-539-2023, https://doi.org/10.5194/tc-17-539-2023, 2023
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Multiple lines of research in ice core science are limited by manually intensive and time-consuming optical microscopy investigations for the detection of insoluble particles, from pollen grains to volcanic shards. To help overcome these limitations and support researchers, we present a novel methodology for the identification and autonomous classification of ice core insoluble particles based on flow image microscopy and neural networks.
Lars Mächler, Daniel Baggenstos, Florian Krauss, Jochen Schmitt, Bernhard Bereiter, Remo Walther, Christoph Reinhard, Béla Tuzson, Lukas Emmenegger, and Hubertus Fischer
Atmos. Meas. Tech., 16, 355–372, https://doi.org/10.5194/amt-16-355-2023, https://doi.org/10.5194/amt-16-355-2023, 2023
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We present a new method to extract the gases from ice cores and measure their greenhouse gas composition. The ice is sublimated continuously with a near-infrared laser, releasing the gases, which are then analyzed on a laser absorption spectrometer. The main advantage over previous efforts is a low effective resolution of 1–2 cm. This capability is crucial for the analysis of highly thinned ice, as expected from ongoing drilling efforts to extend ice core history further back in time.
Zhiheng Du, Jiao Yang, Lei Wang, Ninglian Wang, Anders Svensson, Zhen Zhang, Xiangyu Ma, Yaping Liu, Shimeng Wang, Jianzhong Xu, and Cunde Xiao
Earth Syst. Sci. Data, 14, 5349–5365, https://doi.org/10.5194/essd-14-5349-2022, https://doi.org/10.5194/essd-14-5349-2022, 2022
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A dataset of the radiogenic strontium and neodymium isotopic compositions from the three poles (the third pole, the Arctic, and Antarctica) were integrated to obtain new findings. The dataset enables us to map the standardized locations in the three poles, while the use of sorting criteria related to the sample type permits us to trace the dust sources and sinks. The purpose of this dataset is to try to determine the variable transport pathways of dust at three poles.
Helle Astrid Kjær, Patrick Zens, Samuel Black, Kasper Holst Lund, Anders Svensson, and Paul Vallelonga
Clim. Past, 18, 2211–2230, https://doi.org/10.5194/cp-18-2211-2022, https://doi.org/10.5194/cp-18-2211-2022, 2022
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Six shallow cores from northern Greenland spanning a distance of 426 km were retrieved during a traversal in 2015. We identify several recent acid horizons associated with Icelandic eruptions and eruptions in the Barents Sea region and obtain a robust forest fire proxy associated primarily with Canadian forest fires. We also observe an increase in the large dust particle fluxes that we attribute to an activation of Greenland local sources in recent years (1998–2015).
Johannes Lohmann and Anders Svensson
Clim. Past, 18, 2021–2043, https://doi.org/10.5194/cp-18-2021-2022, https://doi.org/10.5194/cp-18-2021-2022, 2022
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Major volcanic eruptions are known to cause considerable short-term impacts on the global climate. Their influence on long-term climate variability and regime shifts is less well-understood. Here we show that very large, bipolar eruptions occurred more frequently than expected by chance just before abrupt climate change events in the last glacial period (Dansgaard–Oeschger events). Thus, such large eruptions may in some cases act as short-term triggers for abrupt regime shifts of the climate.
Eric W. Wolff, Hubertus Fischer, Tas van Ommen, and David A. Hodell
Clim. Past, 18, 1563–1577, https://doi.org/10.5194/cp-18-1563-2022, https://doi.org/10.5194/cp-18-1563-2022, 2022
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Projects are underway to drill ice cores in Antarctica reaching 1.5 Myr back in time. Dating such cores will be challenging. One method is to match records from the new core against datasets from existing marine sediment cores. Here we explore the options for doing this and assess how well the ice and marine records match over the existing 800 000-year time period. We are able to recommend a strategy for using marine data to place an age scale on the new ice cores.
Giulia Sinnl, Mai Winstrup, Tobias Erhardt, Eliza Cook, Camilla Marie Jensen, Anders Svensson, Bo Møllesøe Vinther, Raimund Muscheler, and Sune Olander Rasmussen
Clim. Past, 18, 1125–1150, https://doi.org/10.5194/cp-18-1125-2022, https://doi.org/10.5194/cp-18-1125-2022, 2022
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A new Greenland ice-core timescale, covering the last 3800 years, was produced using the machine learning algorithm StratiCounter. We synchronized the ice cores using volcanic eruptions and wildfires. We compared the new timescale to the tree-ring timescale, finding good alignment both between the common signatures of volcanic eruptions and of solar activity. Our Greenlandic timescales is safe to use for the Late Holocene, provided one uses our uncertainty estimate.
Julien Westhoff, Giulia Sinnl, Anders Svensson, Johannes Freitag, Helle Astrid Kjær, Paul Vallelonga, Bo Vinther, Sepp Kipfstuhl, Dorthe Dahl-Jensen, and Ilka Weikusat
Clim. Past, 18, 1011–1034, https://doi.org/10.5194/cp-18-1011-2022, https://doi.org/10.5194/cp-18-1011-2022, 2022
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We present a melt event record from an ice core from central Greenland, which covers the past 10 000 years. Our record displays warm summer events, which can be used to enhance our understanding of the past climate. We compare our data to anomalies in tree ring width, which also represents summer temperatures, and find a good correlation. Furthermore, we investigate an outstandingly warm event in the year 986 AD or 991 AD, which has not been analyzed before.
Tobias Erhardt, Matthias Bigler, Urs Federer, Gideon Gfeller, Daiana Leuenberger, Olivia Stowasser, Regine Röthlisberger, Simon Schüpbach, Urs Ruth, Birthe Twarloh, Anna Wegner, Kumiko Goto-Azuma, Takayuki Kuramoto, Helle A. Kjær, Paul T. Vallelonga, Marie-Louise Siggaard-Andersen, Margareta E. Hansson, Ailsa K. Benton, Louise G. Fleet, Rob Mulvaney, Elizabeth R. Thomas, Nerilie Abram, Thomas F. Stocker, and Hubertus Fischer
Earth Syst. Sci. Data, 14, 1215–1231, https://doi.org/10.5194/essd-14-1215-2022, https://doi.org/10.5194/essd-14-1215-2022, 2022
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The datasets presented alongside this manuscript contain high-resolution concentration measurements of chemical impurities in deep ice cores, NGRIP and NEEM, from the Greenland ice sheet. The impurities originate from the deposition of aerosols to the surface of the ice sheet and are influenced by source, transport and deposition processes. Together, these records contain detailed, multi-parameter records of past climate variability over the last glacial period.
Jiamei Lin, Anders Svensson, Christine S. Hvidberg, Johannes Lohmann, Steffen Kristiansen, Dorthe Dahl-Jensen, Jørgen Peder Steffensen, Sune Olander Rasmussen, Eliza Cook, Helle Astrid Kjær, Bo M. Vinther, Hubertus Fischer, Thomas Stocker, Michael Sigl, Matthias Bigler, Mirko Severi, Rita Traversi, and Robert Mulvaney
Clim. Past, 18, 485–506, https://doi.org/10.5194/cp-18-485-2022, https://doi.org/10.5194/cp-18-485-2022, 2022
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We employ acidity records from Greenland and Antarctic ice cores to estimate the emission strength, frequency and climatic forcing for large volcanic eruptions from the last half of the last glacial period. A total of 25 volcanic eruptions are found to be larger than any eruption in the last 2500 years, and we identify more eruptions than obtained from geological evidence. Towards the end of the glacial period, there is a notable increase in volcanic activity observed for Greenland.
Laura Crick, Andrea Burke, William Hutchison, Mika Kohno, Kathryn A. Moore, Joel Savarino, Emily A. Doyle, Sue Mahony, Sepp Kipfstuhl, James W. B. Rae, Robert C. J. Steele, R. Stephen J. Sparks, and Eric W. Wolff
Clim. Past, 17, 2119–2137, https://doi.org/10.5194/cp-17-2119-2021, https://doi.org/10.5194/cp-17-2119-2021, 2021
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The ~ 74 ka eruption of Toba was one of the largest eruptions of the last 100 ka. We have measured the sulfur isotopic composition for 11 Toba eruption candidates in two Antarctic ice cores. Sulfur isotopes allow us to distinguish between large eruptions that have erupted material into the stratosphere and smaller ones that reach lower altitudes. Using this we have identified the events most likely to be Toba and place the eruption on the transition into a cold period in the Northern Hemisphere.
Johannes Sutter, Hubertus Fischer, and Olaf Eisen
The Cryosphere, 15, 3839–3860, https://doi.org/10.5194/tc-15-3839-2021, https://doi.org/10.5194/tc-15-3839-2021, 2021
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Projections of global sea-level changes in a warming world require ice-sheet models. We expand the calibration of these models by making use of the internal architecture of the Antarctic ice sheet, which is formed by its evolution over many millennia. We propose that using our novel approach to constrain ice sheet models, we will be able to both sharpen our understanding of past and future sea-level changes and identify weaknesses in the parameterisation of current continental-scale models.
Helle Astrid Kjær, Lisa Lolk Hauge, Marius Simonsen, Zurine Yoldi, Iben Koldtoft, Maria Hörhold, Johannes Freitag, Sepp Kipfstuhl, Anders Svensson, and Paul Vallelonga
The Cryosphere, 15, 3719–3730, https://doi.org/10.5194/tc-15-3719-2021, https://doi.org/10.5194/tc-15-3719-2021, 2021
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Ice core analyses are often done in home laboratories after costly transport of samples from the field. This limits the amount of sample that can be analysed.
Here, we present the first truly field-portable continuous flow analysis (CFA) system for the analysis of impurities in snow, firn and ice cores while still in the field: the lightweight in situ analysis (LISA) box.
LISA is demonstrated in Greenland to reconstruct accumulation, conductivity and peroxide in snow cores.
Tamara Annina Gerber, Christine Schøtt Hvidberg, Sune Olander Rasmussen, Steven Franke, Giulia Sinnl, Aslak Grinsted, Daniela Jansen, and Dorthe Dahl-Jensen
The Cryosphere, 15, 3655–3679, https://doi.org/10.5194/tc-15-3655-2021, https://doi.org/10.5194/tc-15-3655-2021, 2021
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We simulate the ice flow in the onset region of the Northeast Greenland Ice Stream to determine the source area and past accumulation rates of ice found in the EastGRIP ice core. This information is required to correct for bias in ice-core records introduced by the upstream flow effects. Our results reveal that the increasing accumulation rate with increasing upstream distance is predominantly responsible for the constant annual layer thicknesses observed in the upper 900 m of the ice core.
Loïc Schmidely, Christoph Nehrbass-Ahles, Jochen Schmitt, Juhyeong Han, Lucas Silva, Jinwha Shin, Fortunat Joos, Jérôme Chappellaz, Hubertus Fischer, and Thomas F. Stocker
Clim. Past, 17, 1627–1643, https://doi.org/10.5194/cp-17-1627-2021, https://doi.org/10.5194/cp-17-1627-2021, 2021
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Using ancient gas trapped in polar glaciers, we reconstructed the atmospheric concentrations of methane and nitrous oxide over the penultimate deglaciation to study their response to major climate changes. We show this deglaciation to be characterized by modes of methane and nitrous oxide variability that are also found during the last deglaciation and glacial cycle.
David A. Lilien, Daniel Steinhage, Drew Taylor, Frédéric Parrenin, Catherine Ritz, Robert Mulvaney, Carlos Martín, Jie-Bang Yan, Charles O'Neill, Massimo Frezzotti, Heinrich Miller, Prasad Gogineni, Dorthe Dahl-Jensen, and Olaf Eisen
The Cryosphere, 15, 1881–1888, https://doi.org/10.5194/tc-15-1881-2021, https://doi.org/10.5194/tc-15-1881-2021, 2021
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We collected radar data between EDC, an ice core spanning ~800 000 years, and BELDC, the site chosen for a new
oldest icecore at nearby Little Dome C. These data allow us to identify 50 % older internal horizons than previously traced in the area. We fit a model to the ages of those horizons at BELDC to determine the age of deep ice there. We find that there is likely to be 1.5 Myr old ice ~265 m above the bed, with sufficient resolution to preserve desired climatic information.
Marcel Haeberli, Daniel Baggenstos, Jochen Schmitt, Markus Grimmer, Adrien Michel, Thomas Kellerhals, and Hubertus Fischer
Clim. Past, 17, 843–867, https://doi.org/10.5194/cp-17-843-2021, https://doi.org/10.5194/cp-17-843-2021, 2021
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Using the temperature-dependent solubility of noble gases in ocean water, we reconstruct global mean ocean temperature (MOT) over the last 700 kyr using noble gas ratios in air enclosed in polar ice cores. Our record shows that glacial MOT was about 3 °C cooler compared to the Holocene. Interglacials before 450 kyr ago were characterized by about 1.5 °C lower MOT than the Holocene. In addition, some interglacials show transient maxima in ocean temperature related to changes in ocean circulation.
Helle Astrid Kjær, Patrick Zens, Ross Edwards, Martin Olesen, Ruth Mottram, Gabriel Lewis, Christian Terkelsen Holme, Samuel Black, Kasper Holst Lund, Mikkel Schmidt, Dorthe Dahl-Jensen, Bo Vinther, Anders Svensson, Nanna Karlsson, Jason E. Box, Sepp Kipfstuhl, and Paul Vallelonga
The Cryosphere Discuss., https://doi.org/10.5194/tc-2020-337, https://doi.org/10.5194/tc-2020-337, 2021
Manuscript not accepted for further review
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We have reconstructed accumulation in 6 firn cores and 8 snow cores in Northern Greenland and compared with a regional Climate model over Greenland. We find the model underestimate precipitation especially in north-eastern part of the ice cap- an important finding if aiming to reconstruct surface mass balance.
Temperatures at 10 meters depth at 6 sites in Greenland were also determined and show a significant warming since the 1990's of 0.9 to 2.5 °C.
Johannes Lohmann and Anders Svensson
Clim. Past Discuss., https://doi.org/10.5194/cp-2020-160, https://doi.org/10.5194/cp-2020-160, 2020
Manuscript not accepted for further review
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Major volcanic eruptions are known to cause considerable short-term impacts on the global climate. Their influence on long-term climate variability and regime shifts is less well understood. Here we show that very large, bipolar eruptions occurred more frequently than expected by chance just before abrupt climate change events in the last glacial period (the Dansgaard-Oeschger events). Thus, such large eruptions may in some cases act as short-term triggers to abrupt regime shifts of the climate.
Ikumi Oyabu, Kenji Kawamura, Kyotaro Kitamura, Remi Dallmayr, Akihiro Kitamura, Chikako Sawada, Jeffrey P. Severinghaus, Ross Beaudette, Anaïs Orsi, Satoshi Sugawara, Shigeyuki Ishidoya, Dorthe Dahl-Jensen, Kumiko Goto-Azuma, Shuji Aoki, and Takakiyo Nakazawa
Atmos. Meas. Tech., 13, 6703–6731, https://doi.org/10.5194/amt-13-6703-2020, https://doi.org/10.5194/amt-13-6703-2020, 2020
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Air in polar ice cores provides information on past atmosphere and climate. We present a new method for simultaneously measuring eight gases (CH4, N2O and CO2 concentrations; isotopic ratios of N2 and O2; elemental ratios between N2, O2 and Ar; and total air content) from single ice-core samples with high precision.
Bernhard Bereiter, Béla Tuzson, Philipp Scheidegger, André Kupferschmid, Herbert Looser, Lars Mächler, Daniel Baggenstos, Jochen Schmitt, Hubertus Fischer, and Lukas Emmenegger
Atmos. Meas. Tech., 13, 6391–6406, https://doi.org/10.5194/amt-13-6391-2020, https://doi.org/10.5194/amt-13-6391-2020, 2020
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The record of past greenhouse gas composition from ice cores is crucial for our understanding of global climate change. Deciphering this archive requires highly accurate and spatially resolved analysis of the very small amount of gas that is trapped in the ice. This is achieved with a mid-IR laser absorption spectrometer that provides simultaneous, high-precision measurements of CH4, N2O, CO2, and δ13C(CO2) and which will be coupled to a quantitative sublimation extraction method.
Seyedhamidreza Mojtabavi, Frank Wilhelms, Eliza Cook, Siwan M. Davies, Giulia Sinnl, Mathias Skov Jensen, Dorthe Dahl-Jensen, Anders Svensson, Bo M. Vinther, Sepp Kipfstuhl, Gwydion Jones, Nanna B. Karlsson, Sergio Henrique Faria, Vasileios Gkinis, Helle Astrid Kjær, Tobias Erhardt, Sarah M. P. Berben, Kerim H. Nisancioglu, Iben Koldtoft, and Sune Olander Rasmussen
Clim. Past, 16, 2359–2380, https://doi.org/10.5194/cp-16-2359-2020, https://doi.org/10.5194/cp-16-2359-2020, 2020
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We present a first chronology for the East Greenland Ice-core Project (EGRIP) over the Holocene and last glacial termination. After field measurements and processing of the ice-core data, the GICC05 timescale is transferred from the NGRIP core to the EGRIP core by means of matching volcanic events and common patterns (381 match points) in the ECM and DEP records. The new timescale is named GICC05-EGRIP-1 and extends back to around 15 kyr b2k.
Jinhwa Shin, Christoph Nehrbass-Ahles, Roberto Grilli, Jai Chowdhry Beeman, Frédéric Parrenin, Grégory Teste, Amaelle Landais, Loïc Schmidely, Lucas Silva, Jochen Schmitt, Bernhard Bereiter, Thomas F. Stocker, Hubertus Fischer, and Jérôme Chappellaz
Clim. Past, 16, 2203–2219, https://doi.org/10.5194/cp-16-2203-2020, https://doi.org/10.5194/cp-16-2203-2020, 2020
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We reconstruct atmospheric CO2 from the EPICA Dome C ice core during Marine Isotope Stage 6 (185–135 ka) to understand carbon mechanisms under the different boundary conditions of the climate system. The amplitude of CO2 is highly determined by the Northern Hemisphere stadial duration. Carbon dioxide maxima show different lags with respect to the corresponding abrupt CH4 jumps, the latter reflecting rapid warming in the Northern Hemisphere.
Alexander H. Weinhart, Johannes Freitag, Maria Hörhold, Sepp Kipfstuhl, and Olaf Eisen
The Cryosphere, 14, 3663–3685, https://doi.org/10.5194/tc-14-3663-2020, https://doi.org/10.5194/tc-14-3663-2020, 2020
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From 1 m snow profiles along a traverse on the East Antarctic Plateau, we calculated a representative surface snow density of 355 kg m−3 for this region with an error less than 1.5 %.
This density is 10 % higher and density fluctuations seem to happen on smaller scales than climate model outputs suggest. Our study can help improve the parameterization of surface snow density in climate models to reduce the error in future sea level predictions.
Jann Schrod, Dominik Kleinhenz, Maria Hörhold, Tobias Erhardt, Sarah Richter, Frank Wilhelms, Hubertus Fischer, Martin Ebert, Birthe Twarloh, Damiano Della Lunga, Camilla M. Jensen, Joachim Curtius, and Heinz G. Bingemer
Atmos. Chem. Phys., 20, 12459–12482, https://doi.org/10.5194/acp-20-12459-2020, https://doi.org/10.5194/acp-20-12459-2020, 2020
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Ice-nucleating particle (INP) concentrations of the last 6 centuries are presented from an ice core in Greenland. The data are accompanied by physical and chemical aerosol data. INPs are correlated to the dust signal from the ice core and seem to follow the annual input of mineral dust. We find no clear trend in the INP concentration. However, modern-day concentrations are higher and more variable than the concentrations of the past. This might have significant atmospheric implications.
Christine S. Hvidberg, Aslak Grinsted, Dorthe Dahl-Jensen, Shfaqat Abbas Khan, Anders Kusk, Jonas Kvist Andersen, Niklas Neckel, Anne Solgaard, Nanna B. Karlsson, Helle Astrid Kjær, and Paul Vallelonga
The Cryosphere, 14, 3487–3502, https://doi.org/10.5194/tc-14-3487-2020, https://doi.org/10.5194/tc-14-3487-2020, 2020
Short summary
Short summary
The Northeast Greenland Ice Stream (NEGIS) extends around 600 km from its onset in the interior of Greenland to the coast. Several maps of surface velocity and topography in Greenland exist, but accuracy is limited due to the lack of validation data. Here we present results from a 5-year GPS survey in an interior section of NEGIS. We use the data to assess a list of satellite-derived ice velocity and surface elevation products and discuss the implications for the ice stream flow in the area.
Cited articles
Andersen, K. K., Svensson, A., Rasmussen, S. O., Steffensen, J. P., Johnsen, S. J., Bigler, M., Röthlisberger, R., Ruth, U., Siggaard-Andersen, M.-L., Dahl-Jensen, D., Vinther, B. M., and Clausen, H. B.:
The Greenland Ice Core Chronology 2005, 15–42 ka. Part 1: constructing the time scale, Quaternary Sci. Rev., 25, 3246–3257, https://doi.org/10.1016/j.quascirev.2006.08.002, 2006.
Buchardt, S. L. and Dahl-Jensen, D.:
Estimating the basal melt rate at NorthGRIP using a Monte Carlo technique, Ann. Glaciol., 45, 137–142, 2007.
Clausen, H. B. and Hammer, C. U.:
The Laki and Tambora eruptions as revealed in Greenland ice cores from 11 locations, Ann. Glaciol., 10, 16–22, 1988.
Clausen, H. B., Hammer, C. U., Christensen, J., Schott Hvidberg, C., Dahl-Jensen, D., Legrand, M., and Steffensen, J. P.:
1250 years of global volcanism as revealed by central Greenland ice cores, in: Ice core studies of global biogeochemical cycles, edited by: Delmas, R. J., NATO ASI Series, Springer-Verlag, Heidelberg, https://doi.org/10.1007/978-3-642-51172-1, 1995.
Dahl-Jensen, D., Johnsen, S. J., Hammer, C. U., Clausen, H. B., and Jouzel, J.:
Past accumulation rates derived from observed annual layers in the GRIP ice core from Summit, Central Greenland, in: Ice in the Climate System, edited by: Peltier, R. W., NATO ASI Ser. I, Springer-Verlag, New York, 517–532, https://doi.org/10.1007/978-3-642-85016-5, 1993.
Dahl-Jensen, D., Mosegaard, K., Gundestrup, N., Clow, G. D., Johnsen, S. J., Hansen, A. W., and Balling, N.:
Past temperatures directly from the Greenland ice sheet, Science, 282, 268–271, https://doi.org/10.1126/science.282.5387.268, 1998.
Dahl-Jensen, D., Gundestrup, N., Miller, H., Watanabe, O., Johnsen, S. J., Steffensen, J. P., Clausen, H. B., Svensson, A., and Larsen, L. B.:
The NorthGRIP deep drilling program, Ann. Glaciol., 35, 1–4, 2002.
Dansgaard, W., Clausen, H. B., Gundestrup, N., Hammer, C. U., Johnsen, S. J., Kristinsdottir, P. M., and Reeh, N.:
A new Greenland deep ice core, Science, 218, 1273–1277, 1982.
Dansgaard, W., Johnsen, S. J., Clausen, H. B., Dahl-Jensen, D., Gundestrup, N. S., Hammer, C. U., Hvidberg, C. S., Steffensen, J. P., Sveinbjörnsdottir, A. E., Jouzel, J., and Bond, G.:
Evidence for general instability of past climate from a 250-kyr ice-core record, Nature, 364, 218–220, 1993.
Erhardt, T., Jensen, C. M., Borovinskaya, O., and Fischer, H.:
Single Particle Characterization and Total Elemental Concentration Measurements in Polar Ice Using Continuous Flow Analysis-Inductively Coupled Plasma Time-of-Flight Mass Spectrometry, Environ. Sci. Technol., 53, 13275–13283, https://doi.org/10.1021/acs.est.9b03886, 2019.
Erhardt, T., Bigler, M., Federer, U., Gfeller, G., Leuenberger, D., Stowasser, O., Röthlisberger, R., Schüpbach, S., Ruth, U., Twarloh, B., Wegner, A., Goto-Azuma, K., Takayuki, K., Kjær, H. A., Vallelonga, P. T., Siggaard-Andersen, M.-L., Hansson, M. E., Benton, A. K., Fleet, L. G., Mulvaney, R., Thomas, E. R., Abram, N. J., Stocker, T. F., and Fischer, H.: High resolution impurity data for the NorthGRIP ice core, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.935818, 2021a.
Erhardt, T., Bigler, M., Federer, U., Gfeller, G., Leuenberger, D., Stowasser, O., Röthlisberger, R., Schüpbach, S., Ruth, U., Twarloh, B., Wegner, A., Goto-Azuma, K., Takayuki, K., Kjær, H. A., Vallelonga, P. T., Siggaard-Andersen, M.-L., Hansson, M. E., Benton, A. K., Fleet, L. G., Mulvaney, R., Thomas, E. R., Abram, N. J., Stocker, T. F., and Fischer, H.: High resolution impurity data for the NEEM ice core, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.935837, 2021b.
Erhardt, T., Bigler, M., Federer, U., Gfeller, G., Leuenberger, D., Stowasser, O., Röthlisberger, R., Schüpbach, S., Ruth, U., Twarloh, B., Wegner, A., Goto-Azuma, K., Kuramoto, T., Kjær, H. A., Vallelonga, P. T., Siggaard-Andersen, M.-L., Hansson, M. E., Benton, A. K., Fleet, L. G., Mulvaney, R., Thomas, E. R., Abram, N., Stocker, T. F., and Fischer, H.:
High-resolution aerosol concentration data from the Greenland NorthGRIP and NEEM deep ice cores, Earth Syst. Sci. Data, 14, 1215–1231, https://doi.org/10.5194/essd-14-1215-2022, 2022a.
Erhardt, T., Jensen, C. M., and Fischer, H.: High resolution aerosol records over the past 3.8ka from the EastGRIP ice core, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.945293, 2022b.
Erhardt, T., Jensen, C. M., Adolphi, F., Kjær, H. A., Dallmayr, R., Twarloh, B., Behrens, M., Hirabayashi, M., Fukuda, K., Ogata, J., Burgay, F., Scoto, F., Crotti, I., Spagnesi, A., Maffezzoli, N., Segato, D., Paleari, C., Mekhaldi, F., Muscheler, R., Darfeuil, S., and Fischer, H.:
High resolution aerosol data from the top 3.8 ka of the EGRIP ice core, Earth Syst. Sci. Data Discuss. [preprint], https://doi.org/10.5194/essd-2023-176, in review, 2023.
Fischer, H., Rasmussen, S. O., and Fuhrer, K.: High-resolution impurity data from the GRIP ice core, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.942777, 2022.
Fuhrer, K., Neftel, A., Anklin, M., and Maggi, V.:
Continuous measurements of hydrogen peroxide, formaldehyde, calcium and ammonium concentrations along the new GRIP ice core from Summit, Central Greenland, Atmos. Environ., A27, 1873–1880, 1993.
Fuhrer, K., Neftel, A., Anklin, M., Staffelbach, T., and Legrand, M.:
High-resolution ammonium ice core record covering a complete glacial-interglacial cycle, J. Geophys. Res.-Atmos., 101, 4147–4164, 1996.
Fuhrer, K., Wolff, E. W., and Johnsen, S. J.:
Timescales for dust variability in the Greenland Ice Core Project (GRIP) ice core in the last 100,000 years, J. Geophys. Res., 104, 31043–31052, 1999.
Gerber, T. A., Hvidberg, C. S., Rasmussen, S. O., Franke, S., Sinnl, G., Grinsted, A., Jansen, D., and Dahl-Jensen, D.:
Upstream flow effects revealed in the EastGRIP ice core using Monte Carlo inversion of a two-dimensional ice-flow model, The Cryosphere, 15, 3655–3679, https://doi.org/10.5194/tc-15-3655-2021, 2021.
Gfeller, G., Fischer, H., Bigler, M., Schüpbach, S., Leuenberger, D., and Mini, O.:
Representativeness and seasonality of major ion records derived from NEEM firn cores, The Cryosphere, 8, 1855–1870, https://doi.org/10.5194/tc-8-1855-2014, 2014.
Gkinis, V., Simonsen, S. B., Buchardt, S. L., White, J. W. C., and Vinther, B. M.:
Water isotope diffusion rates from the NorthGRIP ice core for the last 16,000 years – Glaciological and paleoclimatic implications, Earth Planet. Sc. Lett., 405, 132–141, https://doi.org/10.1016/j.epsl.2014.08.022, 2014.
Grootes, P. M., Stuiver, M., White, J. W. C., Johnsen, S. J., and Jouzel, J.:
Comparison of oxygen isotope records from the GISP2 and GRIP Greenland ice cores, Nature, 366, 552–554, 1993.
Hammer, C. U.:
Acidity of polar ice cores in relation to absolute dating, past volcanism, and radio-echoes, J. Glaciol., 25, 359–372, 1980.
Hammer, C. U., Clausen, H. B., Dansgaard, W., Neftel, A., Kristinsdottir, P., and Johnson, E.:
Continuous impurity analysis along the Dye-3 deep core, in: Greenland Ice Core: Geophysics, Geochemistry, and the Environment, edited by: Langway Jr., C. C., Oeschger, H., and Dansgaard, W., Geophys. Monogr. Ser., vol. 33, American Geophysical Union (AGU), Washington, D. C., 90–94, 1985.
Hvidberg, C. S., Dahl-Jensen, D., and Waddington, E. D.:
Ice flow between the Greenland Ice Project and Greenland Ice Sheet Project 2 boreholes in central Greenland, J. Geophys. Res., 102, 26851–26859, 1997.
Hvidberg, C. S., Steffensen, J. P., Clausen, H. B., Shoji, H., and Kipfstuhl, J.:
The NorthGRIP ice-core logging procedure: Description and evaluation, Ann. Glaciol., 35, 5–8, 2002.
Johnsen, S. J. and Andersen, U.:
Isotopic diffusion in Greenland firn and ice. Evidence for crystal boundary diffusion, Eos Trans. AGU Fall Meeting, 8–12 December 1997, San Francisco, USA, 78, F7 Poster U21A-24, 1997.
Johnsen, S. J., Clausen, H. B., Dansgaard, W., Fuhrer, K., Gundestrup, N., Hammer, C. U., Iversen, P., Steffensen, J. P., Jouzel, J., and Stauffer, B.:
Irregular glacial interstadials recorded in a new Greenland ice core, Nature, 359, 311–313, 1992.
Johnsen, S. J., Clausen, H. B., Dansgaard, W., Gundestrup, N. S., Hammer, C. U., Andersen, U., Andersen, K. K., Hvidberg, C. S., Dahl-Jensen, D., Steffensen, J. P., Shoji, H., Sveinbjörnsdóttir, Á. E., White, J., Jouzel, J., and Fisher, D.:
The δ18O record along the Greenland Ice Core Project deep ice core and the problem of possible Eemian climatic instability, J. Geophys. Res., 102, 26397–26410, 1997.
Johnsen, S. J., Clausen, H. B., Cuffey, K. M., Hoffmann, G., Schwander, J., and Creyts, T.:
Diffusion of stable isotopes in polar firn and ice: The isotope effect in firn diffusion, in: Physics of Ice Core Records, edited by: Hondoh, T., Hokkaido University Press, Sapporo, ISBN-10 4832902822, ISBN-13 978-4832902824, 121–140, 2000.
Jonsell, U., Hansson, M. E., Siggaard-Andersen, M.-L., and Steffensen, J.-P.:
Comparison of northern and central Greenland ice core records of methanesulfonate covering the last glacial period, J. Geophys. Res., 112, D14313, https://doi.org/10.1029/2006JD007451, 2007.
Kindler, P., Guillevic, M., Baumgartner, M., Schwander, J., Landais, A., and Leuenberger, M.:
Temperature reconstruction from 10 to 120 kyr b2k from the NGRIP ice core, Clim. Past, 10, 887–902, https://doi.org/10.5194/cp-10-887-2014, 2014.
Kipfstuhl, S., Pauer, F., Kuhs, W. F., and Shoji, H.:
Air bubbles and clathrate hydrates in the transition zone of the NGRIP deep ice core, Geophys. Res. Lett., 28, 591–594, 2001.
Lin, J., Svensson, A., Hvidberg, C. S., Lohmann, J., Kristiansen, S., Dahl-Jensen, D., Steffensen, J. P., Rasmussen, S. O., Cook, E., Kjær, H. A., Vinther, B. M., Fischer, H., Stocker, T., Sigl, M., Bigler, M., Severi, M., Traversi, R., and Mulvaney, R.:
Magnitude, frequency and climate forcing of global volcanism during the last glacial period as seen in Greenland and Antarctic ice cores (60–9 ka), Clim. Past, 18, 485–506, https://doi.org/10.5194/cp-18-485-2022, 2022.
Littot, G. C., Mulvaney, R., Röthlisberger, R., Udisti, R., Wolff, E. W., Castellano, E., M. de Angelis, Hansson, M., Sommer, S., and Steffensen, J. P.:
Comparison of analytical methods used for measuring major ions in the EPICA Dome C (Antarctica) ice core, Ann. Glaciol., 35, 299–305, 2002.
McConnell, J.: Greenland and Antarctic ice core data from Sigl et al., JGR, 2013, Arctic Data Center [data set], https://doi.org/10.18739/A2TH15, 2015.
McConnell, J. R.: High-resolution elemental and chemical measurements in the NGRIP2 core, North Greenland, 2015, Arctic Data Center [data set], https://doi.org/10.18739/A20R9M558, 2023.
McConnell, J. R., Wilson, A. I., Stohl, A., Arienzo, M. M., Chellman, N. J., Eckhardt, S., Thompson, E. M., Pollard, A. M., and Steffensen, J. P.:
Lead pollution recorded in Greenland ice indicates European emissions tracked plagues, wars, and imperial expansion during antiquity, P. Natl. Acad. Sci. USA, 115, 5726–5731, https://doi.org/10.1073/pnas.1721818115, 2018.
Mojtabavi, S., Eisen, O., Franke, S., Jansen, D., Steinhage, D., Paden, J. D., Dahl-Jensen, D., Weikusat, I., Eichler, J., and Wilhelms, F.: Specific conductivity measured with the dielectric profiling (DEP) technique on the NGRIP2 ice core (down to 1298.525 m depth), PANGAEA [data set], https://doi.org/10.1594/PANGAEA.922306, 2020a.
Mojtabavi, S., Wilhelms, F., Cook, E., Davies, S. M., Sinnl, G., Skov Jensen, M., Dahl-Jensen, D., Svensson, A., Vinther, B. M., Kipfstuhl, S., Jones, G., Karlsson, N. B., Faria, S. H., Gkinis, V., Kjær, H. A., Erhardt, T., Berben, S. M. P., Nisancioglu, K. H., Koldtoft, I., and Rasmussen, S. O.:
A first chronology for the East Greenland Ice-core Project (EGRIP) over the Holocene and last glacial termination, Clim. Past, 16, 2359–2380, https://doi.org/10.5194/cp-16-2359-2020, 2020b.
Mojtabavi, S., Wilhelms, F., Cook, E., Davies, S. M., Sinnl, G., Skov Jensen, M., Dahl-Jensen, D., Svensson, A. M., Vinther, B. M., Kipfstuhl, S., Karlsson, N. B., Faria, S. H., Gkinis, V., Kjær, H. A., Erhardt, T., Berben, S. M. P., Nisancioglu, K. H., Koldtoft, I., and Rasmussen, S. O.: Acidity measured with the Electrical Conductivity Method (ECM) on the EGRIP ice core (down to 1383.84 m depth), converted to hydrogen ion concentration, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.922199, 2020c.
Mojtabavi, S., Wilhelms, F., Cook, E., Davies, S. M., Sinnl, G., Skov Jensen, M., Dahl-Jensen, D., Svensson, A. M., Vinther, B. M., Kipfstuhl, S., Karlsson, N. B., Faria, S. H., Gkinis, V., Kjær, H. A., Erhardt, T., Berben, S. M. P., Nisancioglu, K. H., Koldtoft, I., and Rasmussen, S. O.: Specific conductivity measured with the dielectric profiling (DEP) technique on the NGRIP1 ice core (down to 1371.69 m depth), PANGAEA [data set], https://doi.org/10.1594/PANGAEA.922191, 2020d.
Mojtabavi, S., Wilhelms, F., Cook, E., Davies, S. M., Sinnl, G., Skov Jensen, M., Dahl-Jensen, D., Svensson, A. M., Vinther, B. M., Kipfstuhl, S., Karlsson, N. B., Faria, S. H., Gkinis, V., Kjær, H. A., Erhardt, T., Berben, S. M. P., Nisancioglu, K. H., Koldtoft, I., and Rasmussen, S. O.: Specific conductivity measured with the dielectric profiling (DEP) technique on the NEEM ice core (down to 1493.295 m depth), PANGAEA [data set], https://doi.org/10.1594/PANGAEA.922193, 2020e.
Mojtabavi, S., Wilhelms, F., Cook, E., Davies, S. M., Sinnl, G., Skov Jensen, M., Dahl-Jensen, D., Svensson, A. M., Vinther, B. M., Kipfstuhl, S., Karlsson, N. B., Faria, S. H., Gkinis, V., Kjær, H. A., Erhardt, T., Berben, S. M. P., Nisancioglu, K. H., Koldtoft, I., and Rasmussen, S. O.: Specific conductivity measured with the dielectric profiling (DEP) technique on the EGRIP ice core, 13.77–1383.84 m depth, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.919313, 2020f.
Mojtabavi, S., Eisen, O., Franke, S., Jansen, D., Steinhage, D., Paden, J., Dahl-Jensen, D., Weikusat, I., Eichler, J., and Wilhelms, F.:
Origin of englacial stratigraphy at three deep ice core sites of the Greenland Ice Sheet by synthetic radar modelling, J. Glaciol., 1–13, https://doi.org/10.1017/jog.2021.137, 2022.
Moore, J. C. and Paren, J. G.:
A new technique for dielectric logging of Antarctic ice cores, J. Phys.-Paris, 48, 155–160, 1987.
Moore, J. C., Mulvaney, R., and Paren, J. G.:
Dielectric stratigraphy of ice: A new technique for determining total ionic concentrations in polar ice cores, Geophys. Res. Lett., 16, 1177–1180, 1989.
Morrison, J., Brockwell, T., Merren, T., Fourel, F., and Phillips, A. M.:
On-line high-precision stable hydrogen isotopic analyses on nanoliter water samples, Anal. Chem., 73, 3570–3575, https://doi.org/10.1021/ac001447t, 2001.
NEEM community members:
Eemian interglacial reconstructed from a Greenland folded ice core, Nature, 493, 489–494, https://doi.org/10.1038/nature11789, 2013.
Neftel, A., Andrée, M., Schwander, J., Stauffer, B., and Hammer, C. U.:
Measurements of a kind of DC-conductivity on cores from Dye 3, in: Greenland Ice Core: Geophysics, Geochemistry, and the Environment, edited by: Langway Jr., C. C., Oeschger, H., and Dansgaard, W., Geophys. Monogr. Ser., vol. 33, American Geophysical Union (AGU), Washington D. C., 32–38, 1985.
North Greenland Ice Core Project members:
High-resolution record of Northern Hemisphere climate extending into the last interglacial period, Nature, 431, 147–151, 2004.
Plummer, C. T., Curran, M. A. J., van Ommen, T. D., Rasmussen, S. O., Moy, A. D., Vance, T. R., Clausen, H. B., Vinther, B. M., and Mayewski, P. A.:
An independently dated 2000-yr volcanic record from Law Dome, East Antarctica, including a new perspective on the dating of the 1450s CE eruption of Kuwae, Vanuatu, Clim. Past, 8, 1929–1940, https://doi.org/10.5194/cp-8-1929-2012, 2012.
Rasmussen, S. O. and Ruth, U.: High-resolution dust concentrations from the NGRIP2 ice core, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.945447, 2022.
Rasmussen, S. O. and Vinther, B. M.: DYE-3 ice core detailed water-isotope data, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.942945, 2022a.
Rasmussen, S. O. and Vinther, B. M.: DYE-3 4B ice core detailed water isotope data, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.942751, 2022b.
Rasmussen, S. O. and Vinther, B. M.: GRIP ice core detailed water isotope (δ18O) data, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.942851, 2022c.
Rasmussen, S. O. and Vinther, B. M.: DYE-3 18C ice core detailed water isotope data, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.942937, 2022d.
Rasmussen, S. O., Andersen, K. K., Svensson, A. M., Steffensen, J. P., Vinther, B. M., Clausen, H. B., Siggaard-Andersen, M.-L., Johnsen, S. J., Larsen, L. B., Dahl-Jensen, D., Bigler, M., Röthlisberger, R., Fischer, H., Goto-Azuma, K., Hansson, M. E., and Ruth, U.:
A new Greenland ice core chronology for the last glacial termination, J. Geophys. Res., 111, D06102, https://doi.org/10.1029/2005JD006079, 2006.
Rasmussen, S. O., Abbott, P. M., Blunier, T., Bourne, A. J., Brook, E., Buchardt, S. L., Buizert, C., Chappellaz, J., Clausen, H. B., Cook, E., Dahl-Jensen, D., Davies, S. M., Guillevic, M., Kipfstuhl, S., Laepple, T., Seierstad, I. K., Severinghaus, J. P., Steffensen, J. P., Stowasser, C., Svensson, A., Vallelonga, P., Vinther, B. M., Wilhelms, F., and Winstrup, M.:
A first chronology for the North Greenland Eemian Ice Drilling (NEEM) ice core, Clim. Past, 9, 2713–2730, https://doi.org/10.5194/cp-9-2713-2013, 2013a.
Rasmussen, S. O., Abbott, P. M., Blunier, T., Bourne, M., Brook, E. J., Buchardt, S. L., Buizert, C., Chappellaz, J. A., Clausen, H. B., Cook, E., Dahl-Jensen, D., Davies, S. M., Guillevic, M., Kipfstuhl, S., Laepple, T., Seierstad, I. K., Severinghaus, J. P., Steffensen, J. P., Stowasser, C., Svensson, A. M., Vallelonga, P. T., Vinther, B. M., Wilhelms, F., and Winstrup, M.: Specific conductivity and hydrogen ions measured on two ice core (NEEM and NGRIP), PANGAEA [data set], https://doi.org/10.1594/PANGAEA.831528, 2013b.
Rasmussen, S. O., Hansen, S. B., Dahl-Jensen, D., Schwander, J., Steffensen, J. P., and Vinther, B. M.: Electrical conductivity measurements (ECM) from the DYE-3 ice core, Greenland, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.942849, 2022a.
Rasmussen, S. O., Hansen, S. B., Dahl-Jensen, D., Schwander, J., Steffensen, J. P., and Vinther, B. M.: Electrical conductivity measurements (ECM) from the DYE-3 4B ice core, Greenland, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.942843, 2022b.
Rasmussen, S. O., Hansen, S. B., Dahl-Jensen, D., Schwander, J., Steffensen, J. P., and Vinther, B. M.: Electrical conductivity measurements (ECM) from the DYE-3 18C ice core, Greenland, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.942847, 2022c.
Rasmussen, S. O., Hansen, S. B., Hvidberg, C. S., Dahl-Jensen, D., and Steffensen, J. P.: Electrical conductivity measurements (ECM) from the GRIP ice core, central Greenland, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.942944, 2022d.
Rasmussen, S. O., Svensson, A. M., and Vinther, B. M.: Greenland Ice-Core Chronology 2005 (GICC05) annual layer depths for various Greenland ice cores, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.943195, 2022e.
Reeh, N., Johnsen, S. J., and Dahl-Jensen, D.:
Dating the Dye 3 Deep Ice Core by Flow Model Calculations, in: Greenland Ice Core: Geophysics, Geochemistry, and the Environment, edited by: Langway Jr., C. C., Oeschger, H., and Dansgaard, W., Geophysical Monograph Series Greenland Ice Core: Geophysics, Geochemistry, and the Environment
American Geophysical Union, 2000 Florida Avenue, NW, Washington, DC 20009, 57–65, https://doi.org/10.1029/GM033p0057,
ISBN 0-87590-057-7, 1985.
Ruth, U., Wagenbach, D., Steffensen, J. P., and Bigler, M.:
Continuous record of microparticle concentration and size distribution in the central Greenland NGRIP ice core during the last glacial period, J. Geophys. Res., 108, 4098, https://doi.org/10.1029/2002JD002376, 2003.
Ruth, U., Bigler, M., Röthlisberger, R., Siggaard-Andersen, M.-L., Kipfstuhl, S., Goto-Azuma, K., Hansson, M. E., Johnsen, S. J., Lu, H., and Steffensen, J. P.:
Ice core evidence for a very tight link between North Atlantic and east Asian glacial climate, Geophys. Res. Lett., 34, L03706, https://doi.org/10.1029/2006GL027876, 2007.
Röthlisberger, R., Bigler, M., Hutterli, M., Sommer, S., Stauffer, B., Junghans, H. G., and Wagenbach, D.:
Technique for continuous high-resolution analysis of trace substances in firn and ice cores, Environ. Sci. Technol., 34, 338–342, 2000.
Sigg, A., Fuhrer, K., Anklin, M., Staffelbach, T., and Zurmühle, D.:
A continuous analysis technique for trace species in ice cores, Environ. Sci. Technol., 28, 204–209, 1994.
Siggaard-Andersen, M.-L., Steffensen, J. P., and Fischer, H.:
Lithium in Greenland ice cores measured by ion chromatography, Ann. Glaciol., 35, 243–249, 2002.
Siggaard-Andersen, M.-L., Hansson, M. E., Steffensen, J. P., Jonsell, U., and Rasmussen, S. O.: NorthGRIP ice-core record of major ions measured using ion chromatography covering the last two millennia and additional short Holocene sections, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.944172, 2022.
Sigl, M. and McConnell, J. R.:
NEEM-2011-S1 ice-core aerosol record (conductivity, NH4, NO3, BC, acidity, Na, Mg, S, Ca, Mn, Sr, Ce) in NW-Greenland at 2 cm resolution from 86-1997 CE on the annual-layer counted NS1-2011 chronology, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.940553, 2022.
Sigl, M., McConnell, J. R., Layman, L., Maselli, O., McGwire, K., Pasteris, D., Dahl-Jensen, D., Steffensen, J. P., Vinther, B., Edwards, R., Mulvaney, R., and Kipfstuhl, S.:
A new bipolar ice core record of volcanism from WAIS Divide and NEEM and implications for climate forcing of the last 2000 years, J. Geophys. Res.-Atmos., 118, 1151–1169, https://doi.org/10.1029/2012JD018603, 2013.
Sigl, M., Winstrup, M., McConnell, J. R., Welten, K. C., Plunkett, G., Ludlow, F., Büntgen, U., Caffee, M., Chellman, N., Dahl-Jensen, D., Fischer, H., Kipfstuhl, S., Kostick, C., Maselli, O. J., Mekhaldi, F., Mulvaney, R., Muscheler, R., Pasteris, D. R., Pilcher, J. R., Salzer, M., Schüpbach, S., Steffensen, J. P., Vinther, B. M., and Woodruff, T. E.:
Timing and climate forcing of volcanic eruptions for the past 2,500 years, Nature, 523, 543–549, https://doi.org/10.1038/nature14565, 2015.
Sinnl, G., Winstrup, M., Erhardt, T., Cook, E., Jensen, C. M., Svensson, A., Vinther, B. M., Muscheler, R., and Rasmussen, S. O.:
A multi-ice-core, annual-layer-counted Greenland ice-core chronology for the last 3800 years: GICC21, Clim. Past, 18, 1125–1150, https://doi.org/10.5194/cp-18-1125-2022, 2022.
Steffensen, J. P., Andersen, K. K., Bigler, M., Clausen, H. B., Dahl-Jensen, D., Fischer, H., Goto-Azuma, K., Hansson, M., Johnsen, S. J., Jouzel, J., Masson-Delmotte, V., Popp, T., Rasmussen, S. O., Röthlisberger, R., Ruth, U., Stauffer, B., Siggaard-Andersen, M.-L., Sveinbjörnsdóttir, Á. E., Svensson, A., and White, J. W. C.:
High-resolution Greenland ice core data show abrupt climate change happens in few years, Science, 321, 680–684, 2008.
Svensson, A., Nielsen, S. W., Kipfstuhl, S., Johnsen, S. J., Steffensen, J. P., Bigler, M., Ruth, U., and Röthlisberger, R.:
Visual stratigraphy of the North Greenland Ice Core Project (NorthGRIP) ice core during the last glacial period, J. Geophys. Res., 110, D02108, https://doi.org/10.1029/2004JD005134, 2005.
Svensson, A., Andersen, K. K., Bigler, M., Clausen, H. B., Dahl-Jensen, D., Davies, S. M., Johnsen, S. J., Muscheler, R., Parrenin, F., Rasmussen, S. O., Röthlisberger, R., Seierstad, I., Steffensen, J. P., and Vinther, B. M.:
A 60 000 year Greenland stratigraphic ice core chronology, Clim. Past, 4, 47–57, https://doi.org/10.5194/cp-4-47-2008, 2008.
Svensson, A. M., Kipfstuhl, S., and Steffensen, J. P.: Line-scan grey-scale intensity profile from the NGRIP2 ice core, Greenland, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.941174, 2022.
Vallelonga, P., Christianson, K., Alley, R. B., Anandakrishnan, S., Christian, J. E. M., Dahl-Jensen, D., Gkinis, V., Holme, C., Jacobel, R. W., Karlsson, N. B., Keisling, B. A., Kipfstuhl, S., Kjær, H. A., Kristensen, M. E. L., Muto, A., Peters, L. E., Popp, T., Riverman, K. L., Svensson, A. M., Tibuleac, C., Vinther, B. M., Weng, Y., and Winstrup, M.:
Initial results from geophysical surveys and shallow coring of the Northeast Greenland Ice Stream (NEGIS), The Cryosphere, 8, 1275–1287, https://doi.org/10.5194/tc-8-1275-2014, 2014.
Vinther, B. M., Clausen, H. B., Johnsen, S. J., Rasmussen, S. O., Andersen, K. K., Buchardt, S. L., Dahl-Jensen, D., Seierstad, I. K., Siggaard-Andersen, M.-L., Steffensen, J. P., Svensson, A. M., Olsen, J., and Heinemeier, J.:
A synchronized dating of three Greenland ice cores throughout the Holocene, J. Geophys. Res., 111, D13102, https://doi.org/10.1029/2005JD006921, 2006.
Vinther, B. M., Jones, P. D., Briffa, K. R., Clausen, H. B., Andersen, K. K., Dahl-Jensen, D., and Johnsen, S. J.:
Climatic signals in multiple highly resolved stable isotope records from Greenland, Quaternary Sci. Rev., 29, 522–538, https://doi.org/10.1016/j.quascirev.2009.11.002, 2010.
Whillans, I. M., Jezek, K. C., Drew, A. R., and Gundestrup, N.:
Ice flow leading to the deep core hole at Dye 3, Greenland, Ann. Glaciol., 5, 190–195, 1984.
Wilhelms, F.:
Leitfähigkeits- und Dichtemessung an Eisbohrkernen (Measuring the conductivity and density of ice cores), Berichte zur Polarforschung (Reports on Polar Research), 191, 224p, https://doi.org/10.2312/BzP_0191_1996, 1996.
Wilhelms, F., Kipfstuhl, J., Miller, H., Heinloth, K., and Firestone, J.:
Precise dielectric profiling of ice cores: a new device with improved guarding and its theory, J. Glaciol., 44, 171–174, 1998.
Wolff, E. W., Chappellaz, J., Blunier, T., Rasmussen, S. O., and Svensson, A.:
Millennial-scale variability during the last glacial: The ice core record, Quaternary Sci. Rev., 29, 2828–2838, https://doi.org/10.1016/j.quascirev.2009.10.013, 2010.
Short summary
Timescales are essential for interpreting palaeoclimate data. The data series presented here were used for annual-layer identification when constructing the timescales named the Greenland Ice-Core Chronology 2005 (GICC05) and the revised version GICC21. Hopefully, these high-resolution data sets will be useful also for other purposes.
Timescales are essential for interpreting palaeoclimate data. The data series presented here...
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