Articles | Volume 18, issue 3
https://doi.org/10.5194/cp-18-485-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/cp-18-485-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
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15 Mar 2022
Research article | Highlight paper |
| 15 Mar 2022
Magnitude, frequency and climate forcing of global volcanism during the last glacial period as seen in Greenland and Antarctic ice cores (60–9 ka)
Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, 2100, Denmark
Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, 2100, Denmark
Christine S. Hvidberg
Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, 2100, Denmark
Johannes Lohmann
Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, 2100, Denmark
Steffen Kristiansen
Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, 2100, Denmark
Dorthe Dahl-Jensen
Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, 2100, Denmark
Centre for Earth Observation Science, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada
Jørgen Peder Steffensen
Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, 2100, Denmark
Sune Olander Rasmussen
Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, 2100, Denmark
Eliza Cook
Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, 2100, Denmark
Helle Astrid Kjær
Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, 2100, Denmark
Bo M. Vinther
Physics of Ice, Climate and Earth, Niels Bohr Institute, University of Copenhagen, 2100, Denmark
Hubertus Fischer
Climate and Environmental Physics, Physics Institute and Oeschger Center for Climate Change Research, University of Bern, Sidlerstrasse 5, Bern, Switzerland
Thomas Stocker
Climate and Environmental Physics, Physics Institute and Oeschger Center for Climate Change Research, University of Bern, Sidlerstrasse 5, Bern, Switzerland
Michael Sigl
Climate and Environmental Physics, Physics Institute and Oeschger Center for Climate Change Research, University of Bern, Sidlerstrasse 5, Bern, Switzerland
Matthias Bigler
Climate and Environmental Physics, Physics Institute and Oeschger Center for Climate Change Research, University of Bern, Sidlerstrasse 5, Bern, Switzerland
Mirko Severi
Department of Chemistry, University of Florence, Florence, Italy
Rita Traversi
Department of Chemistry, University of Florence, Florence, Italy
Robert Mulvaney
British Antarctic Survey, Cambridge, UK
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Sune Olander Rasmussen, Dorthe Dahl-Jensen, Hubertus Fischer, Katrin Fuhrer, Steffen Bo Hansen, Margareta Hansson, Christine Schøtt Hvidberg, Ulf Jonsell, Sepp Kipfstuhl, Urs Ruth, Jakob Schwander, Marie-Louise Siggaard-Andersen, Giulia Sinnl, Jørgen Peder Steffensen, Anders M. Svensson, and Bo Vinther
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2022-361, https://doi.org/10.5194/essd-2022-361, 2023
Preprint under review for ESSD
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Time scales are essential for interpreting palaeoclimate data. The data series presented here were used for annual-layer identification when constructing the time scales 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.
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.
Guangyu Li, Elise K. Wilbourn, Zezhen Cheng, Jörg Wieder, Allison Fagerson, Jan Henneberger, Ghislain Motos, Rita Traversi, Sarah D. Brooks, Mauro Mazzola, Swarup China, Athanasios Nenes, Ulrike Lohmann, Naruki Hiranuma, and Zamin A. Kanji
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2023-18, https://doi.org/10.5194/acp-2023-18, 2023
Preprint under review for ACP
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In this work, we present results from an Arctic field campaign (NASCENT) in Ny-Ålesund, Svalbard, on the abundance, variability, physicochemical properties and potential sources of ice-nucleating particles relevant for mixed-phase cloud formation. This work improves the data coverage of Arctic INPs and aerosol properties, allowing for the validation of models predicting cloud microphysical and radiative properties of mixed-phase clouds in the rapidly warming Arctic.
Susanne Preunkert, Pascal Bohleber, Michel Legrand, Hubertus Fischer, Adrien Gilbert, Tobias Erhardt, Roland Purtschert, Lars Zipf, Astrid Waldner, and Joseph R. McConnell
The Cryosphere Discuss., https://doi.org/10.5194/tc-2022-259, https://doi.org/10.5194/tc-2022-259, 2023
Preprint under review for TC
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Being close to European pollution source regions makes ice cores from Alpine glaciers important to reconstruct past anthropogenic changes over Europe. Three ice cores covering the 20th century were extracted at the same place at the Col du Dôme (4250 masl, French Alps) in 1994, 2004, and 2012. Combining chemical profiles, bomb test markers and 210Pb profiles, used as footprints of crevasses, allowed to highlight changes over time of the depth-age characteristics at an Alpine drill site.
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.
Nicolas Stoll, Julien Westhoff, Pascal Bohleber, Anders Svensson, Dorthe Dahl-Jensen, Carlo Barbante, and Ilka Weikusat
The Cryosphere Discuss., https://doi.org/10.5194/tc-2022-250, https://doi.org/10.5194/tc-2022-250, 2023
Revised manuscript under review for TC
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Impurities in polar ice play a role regarding the climate signal and internal deformation. We bridge different scales using different methods to investigate ice from the last glacial derived from the EGRIP ice core in NE-Greenland. We characterize different types of cloudy bands, frequently occurring milky layers in the ice, and analyses their chemistry with Raman spectroscopy and laser ablation-ICPMS 2D imaging. We derive new insights about impurity localisation and their deposition conditions.
Eric W. Wolff, Andrea Burke, Laura Crick, Emily A. Doyle, Helen M. Innes, Sue H. Mahony, James W. B. Rae, Mirko Severi, and R. Stephen J. Sparks
Clim. Past, 19, 23–33, https://doi.org/10.5194/cp-19-23-2023, https://doi.org/10.5194/cp-19-23-2023, 2023
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Large volcanic eruptions leave an imprint of a spike of sulfate deposition that can be measured in ice cores. Here we use a method that logs the number and size of large eruptions recorded in an Antarctic core in a consistent way through the last 200 000 years. The rate of recorded eruptions is variable but shows no trends. In particular, there is no increase in recorded eruptions during deglaciation periods. This is consistent with most recorded eruptions being from lower latitudes.
Xavier Giraud, Mélanie Baroni, and Rita Traversi
EGUsphere, https://doi.org/10.5194/egusphere-2022-1455, https://doi.org/10.5194/egusphere-2022-1455, 2023
Preprint archived
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The snowpack in High Antarctic Plateau is an interface medium between the atmosphere and the firn, where past climate conditions are recorded. Originating mainly from oceanic sources, chlorine is deposited along with snow. We propose a mechanism implying the diffusion of HCl at the scale of snow grains, longing a few decades for its release to the Antarctic atmosphere. Based on this scenario, the fate of the anthropogenic 36Cl originating from the nuclear tests can be forcasted.
Elizabeth R. Thomas, Diana O. Vladimirova, Dieter R. Tetzner, B. Daniel Emanuelsson, Nathan Chellman, Daniel A. Dixon, Hugues Goosse, Mackenzie M. Grieman, Amy C. F. King, Michael Sigl, Danielle Udy, Tessa R. Vance, Dominic A. Winski, V. Holly L. Winton, Nancy A. N. Bertler, Akira Hori, Chavarukonam M. Laluraj, Joseph R. McConnell, Yuko Motizuki, Kazuya Takahashi, Hideaki Motoyama, Yoichi Nakai, Franciéle Schwanck, Jefferson Cardia Simões, Filipe Gaudie Ley Lindau, Mirko Severi, Rita Traversi, Sarah Wauthy, Cunde Xiao, Jiao Yang, Ellen Mosely-Thompson, Tamara Khodzher, Ludmila Golobokova, and Alexey Ekaykin
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2022-368, https://doi.org/10.5194/essd-2022-368, 2022
Preprint under review for ESSD
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The concentration of sodium and sulphate measured in Antarctic ice cores is related to changes in both sea ice and winds. Here we have compiled a database of sodium and sulphate records from 105 ice core sites in Antarctica. The records span all, or part, of the past 2000 years. The records will improve our understanding of how winds and sea ice have changed in the past, and how they have influenced the climate of Antarctica over the past 2000 years.
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.
Tyler J. Fudge, Raphael Sauvage, Linh Vu, Benjamin H. Hills, Mirko Severi, and Edwin D. Waddington
EGUsphere, https://doi.org/10.5194/egusphere-2022-1219, https://doi.org/10.5194/egusphere-2022-1219, 2022
This preprint is open for discussion and under review for Climate of the Past (CP).
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We use the oldest Antarctic ice core to estimate the rate of diffusion of sulfuric acid. Sulfuric acid is a marker of past volcanic activity and is critical in developing ice-core timescales. The rate of diffusion is uncertain and is important to know both for selecting future ice core locations and interpreting ice-core records. We find the effective diffusivity of sulfate is 10 times smaller than previously estimated, indicating the sulfuric acid signals will persist for longer.
Michaela Mühl, Jochen Schmitt, Barbara Seth, James Edward Lee, Jon Shelley Edwards, Edward J. Brook, Thomas Blunier, and Hubertus Fischer
EGUsphere, https://doi.org/10.5194/egusphere-2022-1133, https://doi.org/10.5194/egusphere-2022-1133, 2022
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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-hemispheric difference of methane as well as methane stable isotope records derived from dusty Greenland ice.
Robert Mulvaney, Eric William Wolff, Mackenzie Grieman, Helene Hoffmann, Jack Humby, Christoph Nehrbass-Ahles, Rachael Rhodes, Isobel Rowell, Frédéric Parrenin, Loïc Schmidely, Hubertus Fischer, Thomas Stocker, Marcus Christl, Raimund Muscheler, Amaelle Landais, and Frédéric Prié
Clim. Past Discuss., https://doi.org/10.5194/cp-2022-84, https://doi.org/10.5194/cp-2022-84, 2022
Revised manuscript under review for CP
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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. The 651 m ice core includes ice that is confidently dated to the last interglacial, 126,000 years ago. Older ice is found deeper down, but there are flow disturbances in the deeper ice.
Antoine Grisart, Mathieu Casado, Vasileios Gkinis, Bo Vinther, Philippe Naveau, Mathieu Vrac, Thomas Laepple, Bénédicte Minster, Frederic Prié, Barbara Stenni, Elise Fourré, Hans Christian Steen-Larsen, Jean Jouzel, Martin Werner, Katy Pol, Valérie Masson-Delmotte, Maria Hoerhold, Trevor Popp, and Amaelle Landais
Clim. Past, 18, 2289–2301, https://doi.org/10.5194/cp-18-2289-2022, https://doi.org/10.5194/cp-18-2289-2022, 2022
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This paper presents a compilation of high-resolution (11 cm) water isotopic records, including published and new measurements, for the last 800 000 years from the EPICA Dome C ice core, Antarctica. Using this new combined water isotopes (δ18O and δD) dataset, we study the variability and possible influence of diffusion at the multi-decadal to multi-centennial scale. We observe a stronger variability at the onset of the interglacial interval corresponding to a warm period.
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).
Anja Løkkegaard, Kenneth Mankoff, Christian Zdanowicz, Gary D. Clow, Martin P. Lüthi, Samuel Doyle, Henrik Thomsen, David Fisher, Joel Harper, Andy Aschwanden, Bo M. Vinther, Dorthe Dahl-Jensen, Harry Zekollari, Toby Meierbachtol, Ian McDowell, Neil Humphrey, Anne Solgaard, Nanna B. Karlsson, Shfaqat Abbas Khan, Benjamin Hills, Robert Law, Bryn Hubbard, Poul Christoffersen, Mylène Jacquemart, Robert S. Fausto, and William T. Colgan
The Cryosphere Discuss., https://doi.org/10.5194/tc-2022-138, https://doi.org/10.5194/tc-2022-138, 2022
Revised manuscript under review for TC
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This study presents a database compiling 85 ice temperature profiles from the Greenland ice sheet and peripheral ice caps. Ice viscosity and hence ice flow is highly sensitive to ice temperature. To highlight the value of the data base in evaluating ice flow simulations, profiles from the Greenland ice sheet are compared to a modeled temperature field. Re-occurring discrepancies between modeled and observed temperatures provide insight on the difficulties faced when simulating ice temperatures.
Giulia Sinnl, Florian Adolphi, Marcus Christl, Kees C. Welten, Thomas Woodruff, Marc Caffee, Anders Svensson, Raimund Muscheler, and Sune Olander Rasmussen
Clim. Past Discuss., https://doi.org/10.5194/cp-2022-62, https://doi.org/10.5194/cp-2022-62, 2022
Revised manuscript under review for CP
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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 and 25 thousand years ago.
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.
Fabio Giardi, Silvia Nava, Giulia Calzolai, Giulia Pazzi, Massimo Chiari, Andrea Faggi, Bianca Patrizia Andreini, Chiara Collaveri, Elena Franchi, Guido Nincheri, Alessandra Amore, Silvia Becagli, Mirko Severi, Rita Traversi, and Franco Lucarelli
Atmos. Chem. Phys., 22, 9987–10005, https://doi.org/10.5194/acp-22-9987-2022, https://doi.org/10.5194/acp-22-9987-2022, 2022
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The restriction measures adopted to contain the COVID-19 virus offered a unique opportunity to study urban particulate emissions in the near absence of traffic, which is one of the main emission sources in the urban environment. However, the drastic decrease in this source of particulate matter during the months of national lockdown did not lead to an equal decrease in the total particulate load. This is due to the inverse behavior shown by different sources, especially secondary sources.
Carlton Xavier, Metin Baykara, Robin Wollesen de Jonge, Barbara Altstädter, Petri Clusius, Ville Vakkari, Roseline Thakur, Lisa Beck, Silvia Becagli, Mirko Severi, Rita Traversi, Radovan Krejci, Peter Tunved, Mauro Mazzola, Birgit Wehner, Mikko Sipilä, Markku Kulmala, Michael Boy, and Pontus Roldin
Atmos. Chem. Phys., 22, 10023–10043, https://doi.org/10.5194/acp-22-10023-2022, https://doi.org/10.5194/acp-22-10023-2022, 2022
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The focus of this work is to study and improve our understanding of processes involved in the formation and growth of new particles in a remote Arctic marine environment. We run the 1D model ADCHEM along air mass trajectories arriving at Ny-Ålesund in May 2018. The model finds that ion-mediated H2SO4–NH3 nucleation can explain the observed new particle formation at Ny-Ålesund. The growth of particles is driven via H2SO4 condensation and formation of methane sulfonic acid in the aqueous phase.
Silvia Becagli, Elena Barbaro, Simone Bonamano, Laura Caiazzo, Alcide di Sarra, Matteo Feltracco, Paolo Grigioni, Jost Heintzenberg, Luigi Lazzara, Michel Legrand, Alice Madonia, Marco Marcelli, Chiara Melillo, Daniela Meloni, Caterina Nuccio, Giandomenico Pace, Ki-Tae Park, Suzanne Preunkert, Mirko Severi, Marco Vecchiato, Roberta Zangrando, and Rita Traversi
Atmos. Chem. Phys., 22, 9245–9263, https://doi.org/10.5194/acp-22-9245-2022, https://doi.org/10.5194/acp-22-9245-2022, 2022
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Measurements of phytoplanktonic dimethylsulfide and its oxidation products in the Antarctic atmosphere allow us to understand the role of the oceanic (sea ice melting, Chl α and dimethylsulfoniopropionate) and atmospheric (wind direction and speed, humidity, solar radiation and transport processes) factors in the biogenic aerosol formation, concentration and characteristic ratio between components in an Antarctic coastal site facing the polynya of the Ross Sea.
Michael Sigl, Matthew Toohey, Joseph R. McConnell, Jihong Cole-Dai, and Mirko Severi
Earth Syst. Sci. Data, 14, 3167–3196, https://doi.org/10.5194/essd-14-3167-2022, https://doi.org/10.5194/essd-14-3167-2022, 2022
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Volcanism is a key driver of climate. Based on ice cores from Greenland and Antarctica, we reconstruct its climate impact potential over the Holocene. By aligning records on a well-dated chronology from Antarctica, we resolve long-standing inconsistencies in the dating of past volcanic eruptions. We reconstruct 850 eruptions (which, in total, injected 7410 Tg of sulfur in the stratosphere) and estimate how they changed the opacity of the atmosphere, a prerequisite for climate model simulations.
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.
Markus Stoffel, Christophe Corona, Francis Ludlow, Michael Sigl, Heli Huhtamaa, Emmanuel Garnier, Samuli Helama, Sébastien Guillet, Arlene Crampsie, Katrin Kleemann, Chantal Camenisch, Joseph McConnell, and Chaochao Gao
Clim. Past, 18, 1083–1108, https://doi.org/10.5194/cp-18-1083-2022, https://doi.org/10.5194/cp-18-1083-2022, 2022
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The mid-17th century saw several volcanic eruptions, deteriorating climate, political instability, and famine in Europe, China, and Japan. We analyze impacts of the eruptions on climate but also study their socio-political context. We show that an unambiguous distinction of volcanic cooling or wetting from natural climate variability is not straightforward. It also shows that political instability, poor harvest, and famine cannot only be attributed to volcanic climatic impacts.
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.
Cynthia H. Whaley, Rashed Mahmood, Knut von Salzen, Barbara Winter, Sabine Eckhardt, Stephen Arnold, Stephen Beagley, Silvia Becagli, Rong-You Chien, Jesper Christensen, Sujay Manish Damani, Xinyi Dong, Konstantinos Eleftheriadis, Nikolaos Evangeliou, Gregory Faluvegi, Mark Flanner, Joshua S. Fu, Michael Gauss, Fabio Giardi, Wanmin Gong, Jens Liengaard Hjorth, Lin Huang, Ulas Im, Yugo Kanaya, Srinath Krishnan, Zbigniew Klimont, Thomas Kühn, Joakim Langner, Kathy S. Law, Louis Marelle, Andreas Massling, Dirk Olivié, Tatsuo Onishi, Naga Oshima, Yiran Peng, David A. Plummer, Olga Popovicheva, Luca Pozzoli, Jean-Christophe Raut, Maria Sand, Laura N. Saunders, Julia Schmale, Sangeeta Sharma, Ragnhild Bieltvedt Skeie, Henrik Skov, Fumikazu Taketani, Manu A. Thomas, Rita Traversi, Kostas Tsigaridis, Svetlana Tsyro, Steven Turnock, Vito Vitale, Kaley A. Walker, Minqi Wang, Duncan Watson-Parris, and Tahya Weiss-Gibbons
Atmos. Chem. Phys., 22, 5775–5828, https://doi.org/10.5194/acp-22-5775-2022, https://doi.org/10.5194/acp-22-5775-2022, 2022
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Air pollutants, like ozone and soot, play a role in both global warming and air quality. Atmospheric models are often used to provide information to policy makers about current and future conditions under different emissions scenarios. In order to have confidence in those simulations, in this study we compare simulated air pollution from 18 state-of-the-art atmospheric models to measured air pollution in order to assess how well the models perform.
Aki Virkkula, Henrik Grythe, John Backman, Tuukka Petäjä, Maurizio Busetto, Christian Lanconelli, Angelo Lupi, Silvia Becagli, Rita Traversi, Mirko Severi, Vito Vitale, Patrick Sheridan, and Elisabeth Andrews
Atmos. Chem. Phys., 22, 5033–5069, https://doi.org/10.5194/acp-22-5033-2022, https://doi.org/10.5194/acp-22-5033-2022, 2022
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Optical properties of surface aerosols at Dome C, Antarctica, in 2007–2013 and their potential source areas are presented. The equivalent black carbon (eBC) mass concentrations were compared with eBC measured at three other Antarctic sites: the South Pole (SPO) and two coastal sites, Neumayer and Syowa. Transport analysis suggests that South American BC emissions are the largest contributor to eBC at Dome C.
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.
Marjan Marbouti, Sehyun Jang, Silvia Becagli, Gabriel Navarro, Rita Traversi, Kitack Lee, Tuomo Nieminen, Lisa J. Beck, Markku Kulmala, Veli-Matti Kerminen, and Mikko Sipilä
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-52, https://doi.org/10.5194/acp-2022-52, 2022
Publication in ACP not foreseen
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This research was done to understand and investigate the roles of Chl-a, PP and sea ice extent in controlling and producing the in-situ measured MSA, SA, HIO3, HOM and aerosol concentrations over the Greenland and Barents Seas. Our results provide strong support to the hypothesis that MSA, SA and small-particle concentrations in the Svalbard area are directly linked to ocean biological activity and sea ice melting during springtime.
Julia Schmale, Sangeeta Sharma, Stefano Decesari, Jakob Pernov, Andreas Massling, Hans-Christen Hansson, Knut von Salzen, Henrik Skov, Elisabeth Andrews, Patricia K. Quinn, Lucia M. Upchurch, Konstantinos Eleftheriadis, Rita Traversi, Stefania Gilardoni, Mauro Mazzola, James Laing, and Philip Hopke
Atmos. Chem. Phys., 22, 3067–3096, https://doi.org/10.5194/acp-22-3067-2022, https://doi.org/10.5194/acp-22-3067-2022, 2022
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Long-term data sets of Arctic aerosol properties from 10 stations across the Arctic provide evidence that anthropogenic influence on the Arctic atmospheric chemical composition has declined in winter, a season which is typically dominated by mid-latitude emissions. The number of significant trends in summer is smaller than in winter, and overall the pattern is ambiguous with some significant positive and negative trends. This reflects the mixed influence of natural and anthropogenic emissions.
Gill Plunkett, Michael Sigl, Hans F. Schwaiger, Emma L. Tomlinson, Matthew Toohey, Joseph R. McConnell, Jonathan R. Pilcher, Takeshi Hasegawa, and Claus Siebe
Clim. Past, 18, 45–65, https://doi.org/10.5194/cp-18-45-2022, https://doi.org/10.5194/cp-18-45-2022, 2022
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We report the identification of volcanic ash associated with a sulfate layer in Greenland ice cores previously thought to have been from the Vesuvius 79 CE eruption and which had been used to confirm the precise dating of the Greenland ice-core chronology. We find that the tephra was probably produced by an eruption in Alaska. We show the importance of verifying sources of volcanic signals in ice cores through ash analysis to avoid errors in dating ice cores and interpreting volcanic impacts.
Anne Dallmeyer, Martin Claussen, Stephan J. Lorenz, Michael Sigl, Matthew Toohey, and Ulrike Herzschuh
Clim. Past, 17, 2481–2513, https://doi.org/10.5194/cp-17-2481-2021, https://doi.org/10.5194/cp-17-2481-2021, 2021
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Using the comprehensive Earth system model, MPI-ESM1.2, we explore the global Holocene vegetation changes and interpret them in terms of the Holocene climate change. The model results reveal that most of the Holocene vegetation transitions seen outside the high northern latitudes can be attributed to modifications in the intensity of the global summer monsoons.
Raffaello Nardin, Mirko Severi, Alessandra Amore, Silvia Becagli, Francois Burgay, Laura Caiazzo, Virginia Ciardini, Giuliano Dreossi, Massimo Frezzotti, Sang-Bum Hong, Ishaq Khan, Bianca Maria Narcisi, Marco Proposito, Claudio Scarchilli, Enricomaria Selmo, Andrea Spolaor, Barbara Stenni, and Rita Traversi
Clim. Past, 17, 2073–2089, https://doi.org/10.5194/cp-17-2073-2021, https://doi.org/10.5194/cp-17-2073-2021, 2021
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The first step to exploit all the potential information buried in ice cores is to produce a reliable age scale. Based on chemical and isotopic records from the 197 m Antarctic GV7(B) ice core, accurate dating was achieved and showed that the archive spans roughly the last 830 years. The relatively high accumulation rate allowed us to use the non-sea-salt sulfate seasonal pattern to count annual layers. The accumulation rate reconstruction exhibited a slight increase since the 18th century.
Woon Mi Kim, Richard Blender, Michael Sigl, Martina Messmer, and Christoph C. Raible
Clim. Past, 17, 2031–2053, https://doi.org/10.5194/cp-17-2031-2021, https://doi.org/10.5194/cp-17-2031-2021, 2021
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To understand the natural characteristics and future changes of the global extreme daily precipitation, it is necessary to explore the long-term characteristics of extreme daily precipitation. Here, we used climate simulations to analyze the characteristics and long-term changes of extreme precipitation during the past 3351 years. Our findings indicate that extreme precipitation in the past is associated with internal climate variability and regional surface temperatures.
Frerk Pöppelmeier, David J. Janssen, Samuel L. Jaccard, and Thomas F. Stocker
Biogeosciences, 18, 5447–5463, https://doi.org/10.5194/bg-18-5447-2021, https://doi.org/10.5194/bg-18-5447-2021, 2021
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Chromium (Cr) is a redox-sensitive element that holds promise as a tracer of ocean oxygenation and biological activity. We here implemented the oxidation states Cr(III) and Cr(VI) in the Bern3D model to investigate the processes that shape the global Cr distribution. We find a Cr ocean residence time of 5–8 kyr and that the benthic source dominates the tracer budget. Further, regional model–data mismatches suggest strong Cr removal in oxygen minimum zones and a spatially variable benthic source.
Matteo Rinaldi, Naruki Hiranuma, Gianni Santachiara, Mauro Mazzola, Karam Mansour, Marco Paglione, Cheyanne A. Rodriguez, Rita Traversi, Silvia Becagli, David Cappelletti, and Franco Belosi
Atmos. Chem. Phys., 21, 14725–14748, https://doi.org/10.5194/acp-21-14725-2021, https://doi.org/10.5194/acp-21-14725-2021, 2021
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This study aims to add to the still scant ice-nucleating particle (INP) observations in the Arctic environment, investigating INP concentrations and potential sources, during spring and summertime, at the ground-level site of GVB. The lack of a clear concentration seasonal trend, in contrast with previous works, shows an important interannual variability of Arctic INP sources, which may be both terrestrial and marine, outside the Arctic haze period.
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.
Congbo Song, Manuel Dall'Osto, Angelo Lupi, Mauro Mazzola, Rita Traversi, Silvia Becagli, Stefania Gilardoni, Stergios Vratolis, Karl Espen Yttri, David C. S. Beddows, Julia Schmale, James Brean, Agung Ghani Kramawijaya, Roy M. Harrison, and Zongbo Shi
Atmos. Chem. Phys., 21, 11317–11335, https://doi.org/10.5194/acp-21-11317-2021, https://doi.org/10.5194/acp-21-11317-2021, 2021
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We present a cluster analysis of relatively long-term (2015–2019) aerosol aerodynamic volume size distributions up to 20 μm in the Arctic for the first time. The study found that anthropogenic and natural aerosols comprised 27 % and 73 % of the occurrence of the coarse-mode aerosols, respectively. Our study shows that about two-thirds of the coarse-mode aerosols are related to two sea-spray-related aerosol clusters, indicating that sea spray aerosol may more complex in the Arctic environment.
Johannes Lohmann, Daniele Castellana, Peter D. Ditlevsen, and Henk A. Dijkstra
Earth Syst. Dynam., 12, 819–835, https://doi.org/10.5194/esd-12-819-2021, https://doi.org/10.5194/esd-12-819-2021, 2021
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Tipping of one climate subsystem could trigger a cascade of subsequent tipping points and even global-scale climate tipping. Sequential shifts of atmosphere, sea ice and ocean have been recorded in proxy archives of past climate change. Based on this we propose a conceptual model for abrupt climate changes of the last glacial. Here, rate-induced tipping enables tipping cascades in systems with relatively weak coupling. An early warning signal is proposed that may detect such a tipping.
Delia Segato, Maria Del Carmen Villoslada Hidalgo, Ross Edwards, Elena Barbaro, Paul Vallelonga, Helle Astrid Kjær, Marius Simonsen, Bo Vinther, Niccolò Maffezzoli, Roberta Zangrando, Clara Turetta, Dario Battistel, Orri Vésteinsson, Carlo Barbante, and Andrea Spolaor
Clim. Past, 17, 1533–1545, https://doi.org/10.5194/cp-17-1533-2021, https://doi.org/10.5194/cp-17-1533-2021, 2021
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Human influence on fire regimes in the past is poorly understood, especially at high latitudes. We present 5 kyr of fire proxies levoglucosan, black carbon, and ammonium in the RECAP ice core in Greenland and reconstruct for the first time the fire regime in the high North Atlantic region, comprising coastal east Greenland and Iceland. Climate is the main driver of the fire regime, but at 1.1 kyr BP a contribution may be made by the deforestation resulting from Viking colonization of Iceland.
Sehyun Jang, Ki-Tae Park, Kitack Lee, Young Jun Yoon, Kitae Kim, Hyun Young Chung, Eunho Jang, Silvia Becagli, Bang Yong Lee, Rita Traversi, Konstantinos Eleftheriadis, Radovan Krejci, and Ove Hermansen
Atmos. Chem. Phys., 21, 9761–9777, https://doi.org/10.5194/acp-21-9761-2021, https://doi.org/10.5194/acp-21-9761-2021, 2021
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This study provides comprehensive datasets encompassing seasonal and interannual variations in sulfate and MSA concentration in aerosol particles in the Arctic atmosphere. As oxidation products of DMS have important roles in new particle formation and growth, we focused on factors affecting their variability and the branching ratio of DMS oxidation. We found a strong correlation between the ratio and the light condition, chemical properties of particles, and biological activities near Svalbard.
Martina Messmer, Santos J. González-Rojí, Christoph C. Raible, and Thomas F. Stocker
Geosci. Model Dev., 14, 2691–2711, https://doi.org/10.5194/gmd-14-2691-2021, https://doi.org/10.5194/gmd-14-2691-2021, 2021
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Sensitivity experiments with the WRF model are run to find an optimal parameterization setup for precipitation around Mount Kenya at a scale that resolves convection (1 km). Precipitation is compared against many weather stations and gridded observational data sets. Both the temporal correlation of precipitation sums and pattern correlations show that fewer nests lead to a more constrained simulation with higher correlation. The Grell–Freitas cumulus scheme obtains the most accurate results.
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.
Frerk Pöppelmeier, Jeemijn Scheen, Aurich Jeltsch-Thömmes, and Thomas F. Stocker
Clim. Past, 17, 615–632, https://doi.org/10.5194/cp-17-615-2021, https://doi.org/10.5194/cp-17-615-2021, 2021
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The stability of the Atlantic Meridional Overturning Circulation (AMOC) critically depends on its mean state. We simulate the response of the AMOC to North Atlantic freshwater perturbations under different glacial boundary conditions. We find that a closed Bering Strait greatly increases the AMOC's sensitivity to freshwater hosing. Further, the shift from mono- to bistability strongly depends on the chosen boundary conditions, with weaker circulation states exhibiting more abrupt transitions.
Peter M. Abbott, Gill Plunkett, Christophe Corona, Nathan J. Chellman, Joseph R. McConnell, John R. Pilcher, Markus Stoffel, and Michael Sigl
Clim. Past, 17, 565–585, https://doi.org/10.5194/cp-17-565-2021, https://doi.org/10.5194/cp-17-565-2021, 2021
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Volcanic eruptions are a key source of climatic variability, and greater understanding of their past influence will increase the accuracy of future projections. We use volcanic ash from a 1477 CE Icelandic eruption in a Greenlandic ice core as a temporal fix point to constrain the timing of two eruptions in the 1450s CE and their climatic impact. Despite being the most explosive Icelandic eruption in the last 1200 years, the 1477 CE event had a limited impact on Northern Hemisphere climate.
Andreas Plach, Bo M. Vinther, Kerim H. Nisancioglu, Sindhu Vudayagiri, and Thomas Blunier
Clim. Past, 17, 317–330, https://doi.org/10.5194/cp-17-317-2021, https://doi.org/10.5194/cp-17-317-2021, 2021
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In light of recent large-scale melting of the Greenland ice sheet
(GrIS), e.g., in the summer of 2012 several days with surface melt
on the entire ice sheet (including elevations above 3000 m), we use
computer simulations to estimate the amount of melt during a
warmer-than-present period of the past. Our simulations show more
extensive melt than today. This is important for the interpretation of
ice cores which are used to reconstruct the evolution of the ice sheet
and the climate.
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.
Dimitri Osmont, Sandra Brugger, Anina Gilgen, Helga Weber, Michael Sigl, Robin L. Modini, Christoph Schwörer, Willy Tinner, Stefan Wunderle, and Margit Schwikowski
The Cryosphere, 14, 3731–3745, https://doi.org/10.5194/tc-14-3731-2020, https://doi.org/10.5194/tc-14-3731-2020, 2020
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In this interdisciplinary case study, we were able to link biomass burning emissions from the June 2017 wildfires in Portugal to their deposition in the snowpack at Jungfraujoch, Swiss Alps. We analysed black carbon and charcoal in the snowpack, calculated backward trajectories, and monitored the fire evolution by remote sensing. Such case studies help to understand the representativity of biomass burning records in ice cores and how biomass burning tracers are archived in the snowpack.
Jeemijn Scheen and Thomas F. Stocker
Earth Syst. Dynam., 11, 925–951, https://doi.org/10.5194/esd-11-925-2020, https://doi.org/10.5194/esd-11-925-2020, 2020
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Variability of sea surface temperatures (SST) in 1200–2000 CE is quite well-known, but the history of deep ocean temperatures is not. Forcing an ocean model with these SSTs, we simulate temperatures in the ocean interior. The circulation changes alter the amplitude and timing of deep ocean temperature fluctuations below 2 km depth, e.g. delaying the atmospheric signal by ~ 200 years in the deep Atlantic. Thus ocean circulation changes are shown to be as important as SST changes at these depths.
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
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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.
Jesper Sjolte, Florian Adolphi, Bo M. Vinther, Raimund Muscheler, Christophe Sturm, Martin Werner, and Gerrit Lohmann
Clim. Past, 16, 1737–1758, https://doi.org/10.5194/cp-16-1737-2020, https://doi.org/10.5194/cp-16-1737-2020, 2020
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In this study we investigate seasonal climate reconstructions produced by matching climate model output to ice core and tree-ring data, and we evaluate the model–data reconstructions against meteorological observations. The reconstructions capture the main patterns of variability in sea level pressure and temperature in summer and winter. The performance of the reconstructions depends on seasonal climate variability itself, and definitions of seasons can be optimized to capture this variability.
James E. Lee, Edward J. Brook, Nancy A. N. Bertler, Christo Buizert, Troy Baisden, Thomas Blunier, V. Gabriela Ciobanu, Howard Conway, Dorthe Dahl-Jensen, Tyler J. Fudge, Richard Hindmarsh, Elizabeth D. Keller, Frédéric Parrenin, Jeffrey P. Severinghaus, Paul Vallelonga, Edwin D. Waddington, and Mai Winstrup
Clim. Past, 16, 1691–1713, https://doi.org/10.5194/cp-16-1691-2020, https://doi.org/10.5194/cp-16-1691-2020, 2020
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The Roosevelt Island ice core was drilled to investigate climate from the eastern Ross Sea, West Antarctica. We describe the ice age-scale and gas age-scale of the ice core for 0–763 m (83 000 years BP). Old ice near the bottom of the core implies the ice dome existed throughout the last glacial period and that ice streaming was active in the region. Variations in methane, similar to those used as evidence of early human influence on climate, were observed prior to significant human populations.
Anders Svensson, Dorthe Dahl-Jensen, Jørgen Peder Steffensen, Thomas Blunier, Sune O. Rasmussen, Bo M. Vinther, Paul Vallelonga, Emilie Capron, Vasileios Gkinis, Eliza Cook, Helle Astrid Kjær, Raimund Muscheler, Sepp Kipfstuhl, Frank Wilhelms, Thomas F. Stocker, Hubertus Fischer, Florian Adolphi, Tobias Erhardt, Michael Sigl, Amaelle Landais, Frédéric Parrenin, Christo Buizert, Joseph R. McConnell, Mirko Severi, Robert Mulvaney, and Matthias Bigler
Clim. Past, 16, 1565–1580, https://doi.org/10.5194/cp-16-1565-2020, https://doi.org/10.5194/cp-16-1565-2020, 2020
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We identify signatures of large bipolar volcanic eruptions in Greenland and Antarctic ice cores during the last glacial period, which allows for a precise temporal alignment of the ice cores. Thereby the exact timing of unexplained, abrupt climatic changes occurring during the last glacial period can be determined in a global context. The study thus provides a step towards a full understanding of elements of the climate system that may also play an important role in the future.
Abigail G. Hughes, Tyler R. Jones, Bo M. Vinther, Vasileios Gkinis, C. Max Stevens, Valerie Morris, Bruce H. Vaughn, Christian Holme, Bradley R. Markle, and James W. C. White
Clim. Past, 16, 1369–1386, https://doi.org/10.5194/cp-16-1369-2020, https://doi.org/10.5194/cp-16-1369-2020, 2020
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An ice core drilled on the Renland ice cap (RECAP) in east-central Greenland contains a continuous climate record dating through the last glacial period. Here we present the water isotope record for the Holocene, in which high-resolution climate information is retained for the last 8 kyr. We find that the RECAP water isotope record exhibits seasonal and decadal variability which may reflect sea surface conditions and regional climate variability.
Yuri Galletti, Silvia Becagli, Alcide di Sarra, Margherita Gonnelli, Elvira Pulido-Villena, Damiano M. Sferlazzo, Rita Traversi, Stefano Vestri, and Chiara Santinelli
Biogeosciences, 17, 3669–3684, https://doi.org/10.5194/bg-17-3669-2020, https://doi.org/10.5194/bg-17-3669-2020, 2020
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This paper reports the first data about atmospheric deposition of dissolved organic matter (DOM) on the island of Lampedusa. It also shows the implications for the surface marine layer by studying the impact of atmospheric organic carbon deposition in the marine ecosystem. It is a preliminary study, but it is pioneering and important for having new data that can be crucial in order to understand the impact of atmospheric deposition on the marine carbon cycle in a global climate change scenario.
Fortunat Joos, Renato Spahni, Benjamin D. Stocker, Sebastian Lienert, Jurek Müller, Hubertus Fischer, Jochen Schmitt, I. Colin Prentice, Bette Otto-Bliesner, and Zhengyu Liu
Biogeosciences, 17, 3511–3543, https://doi.org/10.5194/bg-17-3511-2020, https://doi.org/10.5194/bg-17-3511-2020, 2020
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Results of the first globally resolved simulations of terrestrial carbon and nitrogen (N) cycling and N2O emissions over the past 21 000 years are compared with reconstructed N2O emissions. Modelled and reconstructed emissions increased strongly during past abrupt warming events. This evidence appears consistent with a dynamic response of biological N fixation to increasing N demand by ecosystems, thereby reducing N limitation of plant productivity and supporting a land sink for atmospheric CO2.
Niccolò Maffezzoli, Paul Vallelonga, Ross Edwards, Alfonso Saiz-Lopez, Clara Turetta, Helle Astrid Kjær, Carlo Barbante, Bo Vinther, and Andrea Spolaor
Clim. Past, 15, 2031–2051, https://doi.org/10.5194/cp-15-2031-2019, https://doi.org/10.5194/cp-15-2031-2019, 2019
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This study provides the first ice-core-based history of sea ice in the North Atlantic Ocean, reaching 120 000 years back in time. This record was obtained from bromine and sodium measurements in the RECAP ice core, drilled in east Greenland. We found that, during the last deglaciation, sea ice started to melt ~ 17 500 years ago. Over the 120 000 years of the last glacial cycle, sea ice extent was maximal during MIS2, while minimum sea ice extent exists for the Holocene.
Juan Pablo Corella, Niccolo Maffezzoli, Carlos Alberto Cuevas, Paul Vallelonga, Andrea Spolaor, Giulio Cozzi, Juliane Müller, Bo Vinther, Carlo Barbante, Helle Astrid Kjær, Ross Edwards, and Alfonso Saiz-Lopez
Clim. Past, 15, 2019–2030, https://doi.org/10.5194/cp-15-2019-2019, https://doi.org/10.5194/cp-15-2019-2019, 2019
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This study provides the first reconstruction of atmospheric iodine levels in the Arctic during the last 11 700 years from an ice core record in coastal Greenland. Dramatic shifts in iodine level variability coincide with abrupt climatic transitions in the North Atlantic. Since atmospheric iodine levels have significant environmental and climatic implications, this study may serve as a past analog to predict future changes in Arctic climate in response to global warming.
Svante Björck, Jesper Sjolte, Karl Ljung, Florian Adolphi, Roger Flower, Rienk H. Smittenberg, Malin E. Kylander, Thomas F. Stocker, Sofia Holmgren, Hui Jiang, Raimund Muscheler, Yamoah K. K. Afrifa, Jayne E. Rattray, and Nathalie Van der Putten
Clim. Past, 15, 1939–1958, https://doi.org/10.5194/cp-15-1939-2019, https://doi.org/10.5194/cp-15-1939-2019, 2019
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Southern Hemisphere westerlies play a key role in regulating global climate. A lake sediment record on a mid-South Atlantic island shows changes in the westerlies and hydroclimate 36.4–18.6 ka. Before 31 ka the westerlies shifted in concert with the bipolar seesaw mechanism in a fairly warm climate, followed by southerly westerlies and falling temperatures. After 27.5 ka temperatures dropped 3 °C with drier conditions and with shifting westerlies possibly triggering the variable LGM CO2 levels.
Hubertus Fischer, Jochen Schmitt, Michael Bock, Barbara Seth, Fortunat Joos, Renato Spahni, Sebastian Lienert, Gianna Battaglia, Benjamin D. Stocker, Adrian Schilt, and Edward J. Brook
Biogeosciences, 16, 3997–4021, https://doi.org/10.5194/bg-16-3997-2019, https://doi.org/10.5194/bg-16-3997-2019, 2019
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N2O concentrations were subject to strong variations accompanying glacial–interglacial but also rapid climate changes over the last 21 kyr. The sources of these N2O changes can be identified by measuring the isotopic composition of N2O in ice cores and using the distinct isotopic composition of terrestrial and marine N2O. We show that both marine and terrestrial sources increased from the last glacial to the Holocene but that only terrestrial emissions responded quickly to rapid climate changes.
Dominic A. Winski, Tyler J. Fudge, David G. Ferris, Erich C. Osterberg, John M. Fegyveresi, Jihong Cole-Dai, Zayta Thundercloud, Thomas S. Cox, Karl J. Kreutz, Nikolas Ortman, Christo Buizert, Jenna Epifanio, Edward J. Brook, Ross Beaudette, Jeffrey Severinghaus, Todd Sowers, Eric J. Steig, Emma C. Kahle, Tyler R. Jones, Valerie Morris, Murat Aydin, Melinda R. Nicewonger, Kimberly A. Casey, Richard B. Alley, Edwin D. Waddington, Nels A. Iverson, Nelia W. Dunbar, Ryan C. Bay, Joseph M. Souney, Michael Sigl, and Joseph R. McConnell
Clim. Past, 15, 1793–1808, https://doi.org/10.5194/cp-15-1793-2019, https://doi.org/10.5194/cp-15-1793-2019, 2019
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A deep ice core was recently drilled at the South Pole to understand past variations in the Earth's climate. To understand the information contained within the ice, we present the relationship between the depth and age of the ice in the South Pole Ice Core. We found that the oldest ice in our record is from 54 302 ± 519 years ago. Our results show that, on average, 7.4 cm of snow falls at the South Pole each year.
Johannes Lohmann and Peter D. Ditlevsen
Clim. Past, 15, 1771–1792, https://doi.org/10.5194/cp-15-1771-2019, https://doi.org/10.5194/cp-15-1771-2019, 2019
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Greenland ice core records show that the climate of the last glacial period was frequently interrupted by rapid warming events, followed by cooling episodes of vastly different duration. We fit a generic waveform to the noisy ice core record in order to extract a robust climate signal and empirically study what controls the amplitude and duration of the warmings and coolings. We find that cooling transitions are more predictable than warmings and are influenced by different climate forcings.
Johannes Sutter, Hubertus Fischer, Klaus Grosfeld, Nanna B. Karlsson, Thomas Kleiner, Brice Van Liefferinge, and Olaf Eisen
The Cryosphere, 13, 2023–2041, https://doi.org/10.5194/tc-13-2023-2019, https://doi.org/10.5194/tc-13-2023-2019, 2019
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The Antarctic Ice Sheet may have played an important role in moderating the transition between warm and cold climate epochs over the last million years. We find that the Antarctic Ice Sheet grew considerably about 0.9 Myr ago, a time when ice-age–warm-age cycles changed from a
40 000 to a 100 000 year periodicity. Our findings also suggest that ice as old as 1.5 Myr still exists at the bottom of the East Antarctic Ice Sheet despite the major climate reorganisations in the past.
Andrew O. Hoffman, Hans Christian Steen-Larsen, Knut Christianson, and Christine Hvidberg
Geosci. Instrum. Method. Data Syst., 8, 149–159, https://doi.org/10.5194/gi-8-149-2019, https://doi.org/10.5194/gi-8-149-2019, 2019
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We present the design considerations and deployment of an autonomous modular terrestrial rover for ice-sheet exploration that is inexpensive, easy to construct, and allows for instrumentation customization. The rover proved capable of driving over 20 km on a single charge with a drawbar pull of 250 N, which is sufficient to tow commercial ground-penetrating radars. Due to its low cost, low power requirements, and simple modular design, mass deployments of this rover design are practicable.
Eunho Jang, Ki-Tae Park, Young Jun Yoon, Tae-Wook Kim, Sang-Bum Hong, Silvia Becagli, Rita Traversi, Jaeseok Kim, and Yeontae Gim
Atmos. Chem. Phys., 19, 7595–7608, https://doi.org/10.5194/acp-19-7595-2019, https://doi.org/10.5194/acp-19-7595-2019, 2019
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We reported long-term observations (from 2009 to 2016) of the nanoparticles measured at the Antarctic Peninsula (62.2° S, 58.8° W), and satellite-derived estimates of the biological characteristics were analyzed to identify the link between new particle formation and marine biota. The key finding from this research is that the formation of nanoparticles was strongly associated not only with the biomass of phytoplankton but, more importantly, also its taxonomic composition in the Antarctic Ocean.
Manuel Dall'Osto, David C. S. Beddows, Peter Tunved, Roy M. Harrison, Angelo Lupi, Vito Vitale, Silvia Becagli, Rita Traversi, Ki-Tae Park, Young Jun Yoon, Andreas Massling, Henrik Skov, Robert Lange, Johan Strom, and Radovan Krejci
Atmos. Chem. Phys., 19, 7377–7395, https://doi.org/10.5194/acp-19-7377-2019, https://doi.org/10.5194/acp-19-7377-2019, 2019
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We present a cluster analysis of particle size distributions simultaneously collected from three European high Arctic sites centred in the Fram Strait during a 3-year period. Confined for longer time periods by consolidated pack sea ice regions, the Greenland site shows lower ultrafine-mode aerosol concentrations during summer relative to the Svalbard sites. Our study supports international environmental cooperation concerning the Arctic region.
Andreas Born, Michael A. Imhof, and Thomas F. Stocker
The Cryosphere, 13, 1529–1546, https://doi.org/10.5194/tc-13-1529-2019, https://doi.org/10.5194/tc-13-1529-2019, 2019
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We present a new numerical model to simulate the surface energy and mass balance of snow and ice. While similar models exist and cover a wide range of complexity from empirical models to those that simulate the microscopic structure of individual snow grains, we aim to strike a balance between physical completeness and numerical efficiency. This new model will enable physically accurate simulations over timescales of hundreds of millennia, a key requirement of investigating ice age cycles.
Christian Holme, Vasileios Gkinis, Mika Lanzky, Valerie Morris, Martin Olesen, Abigail Thayer, Bruce H. Vaughn, and Bo M. Vinther
Clim. Past, 15, 893–912, https://doi.org/10.5194/cp-15-893-2019, https://doi.org/10.5194/cp-15-893-2019, 2019
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This study investigates the linear relationship between the water isotopes of three East Greenland ice cores and regional temperatures. By comparing the water isotopes with nearby instrumental temperature records and reanalysis data, this study demonstrates that it can be problematic to reconstruct temperatures through regression of water isotope data from coastal ice cores. We further show that the varying linear relationship could be connected with changes in sea ice near the drill site.
Tobias Erhardt, Emilie Capron, Sune Olander Rasmussen, Simon Schüpbach, Matthias Bigler, Florian Adolphi, and Hubertus Fischer
Clim. Past, 15, 811–825, https://doi.org/10.5194/cp-15-811-2019, https://doi.org/10.5194/cp-15-811-2019, 2019
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The cause of the rapid warming events documented in proxy records across the Northern Hemisphere during the last glacial has been a long-standing puzzle in paleo-climate research. Here, we use high-resolution ice-core data from to cores in Greenland to investigate the progression during the onset of these events on multi-annual timescales to test their plausible triggers. We show that atmospheric circulation changes preceded the warming in Greenland and the collapse of the sea ice by a decade.
Heike Wex, Lin Huang, Wendy Zhang, Hayley Hung, Rita Traversi, Silvia Becagli, Rebecca J. Sheesley, Claire E. Moffett, Tate E. Barrett, Rossana Bossi, Henrik Skov, Anja Hünerbein, Jasmin Lubitz, Mareike Löffler, Olivia Linke, Markus Hartmann, Paul Herenz, and Frank Stratmann
Atmos. Chem. Phys., 19, 5293–5311, https://doi.org/10.5194/acp-19-5293-2019, https://doi.org/10.5194/acp-19-5293-2019, 2019
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We found an annual cycle for ice-nucleating particles in the Arctic. These particles are important for Arctic clouds, as they can change the lifetime of clouds. We suggest that higher concentrations of these particles in summertime originate from the Arctic biosphere (both marine and terrestrial). With a warming Arctic, these concentrations may increase further, influencing aerosol–cloud interactions and therewith the observed strong warming of the Arctic.
Mai Winstrup, Paul Vallelonga, Helle A. Kjær, Tyler J. Fudge, James E. Lee, Marie H. Riis, Ross Edwards, Nancy A. N. Bertler, Thomas Blunier, Ed J. Brook, Christo Buizert, Gabriela Ciobanu, Howard Conway, Dorthe Dahl-Jensen, Aja Ellis, B. Daniel Emanuelsson, Richard C. A. Hindmarsh, Elizabeth D. Keller, Andrei V. Kurbatov, Paul A. Mayewski, Peter D. Neff, Rebecca L. Pyne, Marius F. Simonsen, Anders Svensson, Andrea Tuohy, Edwin D. Waddington, and Sarah Wheatley
Clim. Past, 15, 751–779, https://doi.org/10.5194/cp-15-751-2019, https://doi.org/10.5194/cp-15-751-2019, 2019
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We present a 2700-year timescale and snow accumulation history for an ice core from Roosevelt Island, Ross Ice Shelf, Antarctica. We observe a long-term slightly decreasing trend in accumulation during most of the period but a rapid decline since the mid-1960s. The latter is linked to a recent strengthening of the Amundsen Sea Low and the expansion of regional sea ice. The year 1965 CE may thus mark the onset of significant increases in sea-ice extent in the eastern Ross Sea.
Tetsuro Taranczewski, Johannes Freitag, Olaf Eisen, Bo Vinther, Sonja Wahl, and Sepp Kipfstuhl
The Cryosphere Discuss., https://doi.org/10.5194/tc-2018-280, https://doi.org/10.5194/tc-2018-280, 2019
Preprint withdrawn
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We used melt layers detected in ice cores from the Renland ice cap in East Greenland to find evidence of past climate trends in this region. Our record provides such information for the past 10,000 years. We developed an attempt to increase the reliability of such a record by correcting deformation-induced biases. It proves that such simple to obtain melt records can be used to gather information about paleoclimate especially for regions where climate records are sparse.
Jonas Beck, Michael Bock, Jochen Schmitt, Barbara Seth, Thomas Blunier, and Hubertus Fischer
Biogeosciences, 15, 7155–7175, https://doi.org/10.5194/bg-15-7155-2018, https://doi.org/10.5194/bg-15-7155-2018, 2018
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Ice core concentration and stable isotope measurements of atmospheric CH4 give valuable insights into the CH4 cycle of the past. New carbon and hydrogen stable isotope CH4 data measured on ice from both Greenland and Antarctica over the Holocene allow us to draw conclusions on the methane emission processes. In particular, our results cast doubt on a hypothesis proposing early human land use to be responsible for the atmospheric methane concentration increase in the second half of the Holocene.
Florian Adolphi, Christopher Bronk Ramsey, Tobias Erhardt, R. Lawrence Edwards, Hai Cheng, Chris S. M. Turney, Alan Cooper, Anders Svensson, Sune O. Rasmussen, Hubertus Fischer, and Raimund Muscheler
Clim. Past, 14, 1755–1781, https://doi.org/10.5194/cp-14-1755-2018, https://doi.org/10.5194/cp-14-1755-2018, 2018
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The last glacial period was characterized by a number of rapid climate changes seen, for example, as abrupt warmings in Greenland and changes in monsoon rainfall intensity. However, due to chronological uncertainties it is challenging to know how tightly coupled these changes were. Here we exploit cosmogenic signals caused by changes in the Sun and Earth magnetic fields to link different climate archives and improve our understanding of the dynamics of abrupt climate change.
Christoph C. Raible, Martina Messmer, Flavio Lehner, Thomas F. Stocker, and Richard Blender
Clim. Past, 14, 1499–1514, https://doi.org/10.5194/cp-14-1499-2018, https://doi.org/10.5194/cp-14-1499-2018, 2018
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Extratropical cyclones in winter and their characteristics are investigated in depth for the Atlantic European region from 850 to 2100 CE. During the Common Era, cyclone characteristics show pronounced variations mainly caused by internal variability of the coupled climate system. When anthropogenic forcing becomes dominant, a strong increase of extreme cyclone-related precipitation is found due to thermodynamics, though dynamical processes can play an important role during the last millennium.
Andreas Plach, Kerim H. Nisancioglu, Sébastien Le clec'h, Andreas Born, Petra M. Langebroek, Chuncheng Guo, Michael Imhof, and Thomas F. Stocker
Clim. Past, 14, 1463–1485, https://doi.org/10.5194/cp-14-1463-2018, https://doi.org/10.5194/cp-14-1463-2018, 2018
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The Greenland ice sheet is a huge frozen water reservoir which is crucial for predictions of sea level in a warming future climate. Therefore, computer models are needed to reliably simulate the melt of ice sheets. In this study, we use climate model simulations of the last period where it was warmer than today in Greenland. We test different melt models under these climatic conditions and show that the melt models show very different results under these warmer conditions.
Amaëlle Landais, Emilie Capron, Valérie Masson-Delmotte, Samuel Toucanne, Rachael Rhodes, Trevor Popp, Bo Vinther, Bénédicte Minster, and Frédéric Prié
Clim. Past, 14, 1405–1415, https://doi.org/10.5194/cp-14-1405-2018, https://doi.org/10.5194/cp-14-1405-2018, 2018
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During the last glacial–interglacial climate transition (120 000 to 10 000 years before present), Greenland climate and midlatitude North Atlantic climate and water cycle vary in phase over the succession of millennial events. We identify here one notable exception to this behavior with a decoupling unambiguously identified through a combination of water isotopic tracers measured in a Greenland ice core. The midlatitude moisture source becomes warmer and wetter at 16 200 years before present.
Jesper Sjolte, Christophe Sturm, Florian Adolphi, Bo M. Vinther, Martin Werner, Gerrit Lohmann, and Raimund Muscheler
Clim. Past, 14, 1179–1194, https://doi.org/10.5194/cp-14-1179-2018, https://doi.org/10.5194/cp-14-1179-2018, 2018
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Tropical volcanic eruptions and variations in solar activity have been suggested to influence the strength of westerly winds across the North Atlantic. We use Greenland ice core records together with a climate model simulation, and find stronger westerly winds for five winters following tropical volcanic eruptions. We see a delayed response to solar activity of 5 years, and the response to solar minima corresponds well to the cooling pattern during the period known as the Little Ice Age.
Minjie Zheng, Jesper Sjolte, Florian Adolphi, Bo Møllesøe Vinther, Hans Christian Steen-Larsen, Trevor James Popp, and Raimund Muscheler
Clim. Past, 14, 1067–1078, https://doi.org/10.5194/cp-14-1067-2018, https://doi.org/10.5194/cp-14-1067-2018, 2018
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We show the seasonal δ18O data from the NEEM site in northwestern Greenland over the last 150 years. We found that the NEEM summer δ18O signal correlates well with summer temperature in western coastal Greenland, while the NEEM winter δ18O signal correlates well with sea ice concentration in Baffin Bay. In contrast with the winter δ18O data from central/southern Greenland, we find no linkage of NEEM winter δ18O to winter NAO.
Roberto Salzano, Antonello Pasini, Antonietta Ianniello, Mauro Mazzola, Rita Traversi, and Roberto Udisti
Atmos. Chem. Phys., 18, 6959–6969, https://doi.org/10.5194/acp-18-6959-2018, https://doi.org/10.5194/acp-18-6959-2018, 2018
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The radon progeny can describe the circulation of air masses in the Arctic region, evidencing a seasonality and stability dynamics that can influence the persistence of pollutants in the lower layer of the atmosphere. This paper, for the first time, considered high-time resolved radon-progeny measurements in the Arctic region. These data were used for tracing air masses in terms of age, origin, permafrost dynamics, seasonality and local effects.
Johannes Lohmann and Peter D. Ditlevsen
Clim. Past, 14, 609–617, https://doi.org/10.5194/cp-14-609-2018, https://doi.org/10.5194/cp-14-609-2018, 2018
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The climate of the last glacial period was frequently interrupted by rapid warming events, the cause of which is still unknown. One open question is whether the occurrence of events is random or externally controlled. We studied the temporal characteristics of warm and cold phases using statistical null models and find that they are well described as random processes modulated by two different external climate factors. This may help distinguish physical mechanisms for rapid climate change.
Marius Folden Simonsen, Llorenç Cremonesi, Giovanni Baccolo, Samuel Bosch, Barbara Delmonte, Tobias Erhardt, Helle Astrid Kjær, Marco Potenza, Anders Svensson, and Paul Vallelonga
Clim. Past, 14, 601–608, https://doi.org/10.5194/cp-14-601-2018, https://doi.org/10.5194/cp-14-601-2018, 2018
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Ice core dust size distributions are more often measured today by an Abakus laser sensor than by the more technically demanding but also very accurate Coulter counter. However, Abakus measurements consistently give larger particle sizes. We show here that this bias exists because the particles are flat and elongated. Correcting for this gives more accurate Abakus measurements. Furthermore, the shape of the particles can be extracted from a combination of Coulter counter and Abakus measurements.
Masa Kageyama, Pascale Braconnot, Sandy P. Harrison, Alan M. Haywood, Johann H. Jungclaus, Bette L. Otto-Bliesner, Jean-Yves Peterschmitt, Ayako Abe-Ouchi, Samuel Albani, Patrick J. Bartlein, Chris Brierley, Michel Crucifix, Aisling Dolan, Laura Fernandez-Donado, Hubertus Fischer, Peter O. Hopcroft, Ruza F. Ivanovic, Fabrice Lambert, Daniel J. Lunt, Natalie M. Mahowald, W. Richard Peltier, Steven J. Phipps, Didier M. Roche, Gavin A. Schmidt, Lev Tarasov, Paul J. Valdes, Qiong Zhang, and Tianjun Zhou
Geosci. Model Dev., 11, 1033–1057, https://doi.org/10.5194/gmd-11-1033-2018, https://doi.org/10.5194/gmd-11-1033-2018, 2018
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The Paleoclimate Modelling Intercomparison Project (PMIP) takes advantage of the existence of past climate states radically different from the recent past to test climate models used for climate projections and to better understand these climates. This paper describes the PMIP contribution to CMIP6 (Coupled Model Intercomparison Project, 6th phase) and possible analyses based on PMIP results, as well as on other CMIP6 projects.
Taku Umezawa, Carl A. M. Brenninkmeijer, Thomas Röckmann, Carina van der Veen, Stanley C. Tyler, Ryo Fujita, Shinji Morimoto, Shuji Aoki, Todd Sowers, Jochen Schmitt, Michael Bock, Jonas Beck, Hubertus Fischer, Sylvia E. Michel, Bruce H. Vaughn, John B. Miller, James W. C. White, Gordon Brailsford, Hinrich Schaefer, Peter Sperlich, Willi A. Brand, Michael Rothe, Thomas Blunier, David Lowry, Rebecca E. Fisher, Euan G. Nisbet, Andrew L. Rice, Peter Bergamaschi, Cordelia Veidt, and Ingeborg Levin
Atmos. Meas. Tech., 11, 1207–1231, https://doi.org/10.5194/amt-11-1207-2018, https://doi.org/10.5194/amt-11-1207-2018, 2018
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Isotope measurements are useful for separating different methane sources. However, the lack of widely accepted standards and calibration methods for stable carbon and hydrogen isotopic ratios of methane in air has caused significant measurement offsets among laboratories. We conducted worldwide interlaboratory comparisons, surveyed the literature and assessed them systematically. This study may be of help in future attempts to harmonize data sets of isotopic composition of atmospheric methane.
Nancy A. N. Bertler, Howard Conway, Dorthe Dahl-Jensen, Daniel B. Emanuelsson, Mai Winstrup, Paul T. Vallelonga, James E. Lee, Ed J. Brook, Jeffrey P. Severinghaus, Taylor J. Fudge, Elizabeth D. Keller, W. Troy Baisden, Richard C. A. Hindmarsh, Peter D. Neff, Thomas Blunier, Ross Edwards, Paul A. Mayewski, Sepp Kipfstuhl, Christo Buizert, Silvia Canessa, Ruzica Dadic, Helle A. Kjær, Andrei Kurbatov, Dongqi Zhang, Edwin D. Waddington, Giovanni Baccolo, Thomas Beers, Hannah J. Brightley, Lionel Carter, David Clemens-Sewall, Viorela G. Ciobanu, Barbara Delmonte, Lukas Eling, Aja Ellis, Shruthi Ganesh, Nicholas R. Golledge, Skylar Haines, Michael Handley, Robert L. Hawley, Chad M. Hogan, Katelyn M. Johnson, Elena Korotkikh, Daniel P. Lowry, Darcy Mandeno, Robert M. McKay, James A. Menking, Timothy R. Naish, Caroline Noerling, Agathe Ollive, Anaïs Orsi, Bernadette C. Proemse, Alexander R. Pyne, Rebecca L. Pyne, James Renwick, Reed P. Scherer, Stefanie Semper, Marius Simonsen, Sharon B. Sneed, Eric J. Steig, Andrea Tuohy, Abhijith Ulayottil Venugopal, Fernando Valero-Delgado, Janani Venkatesh, Feitang Wang, Shimeng Wang, Dominic A. Winski, V. Holly L. Winton, Arran Whiteford, Cunde Xiao, Jiao Yang, and Xin Zhang
Clim. Past, 14, 193–214, https://doi.org/10.5194/cp-14-193-2018, https://doi.org/10.5194/cp-14-193-2018, 2018
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Temperature and snow accumulation records from the annually dated Roosevelt Island Climate Evolution (RICE) ice core show that for the past 2 700 years, the eastern Ross Sea warmed, while the western Ross Sea showed no trend and West Antarctica cooled. From the 17th century onwards, this dipole relationship changed. Now all three regions show concurrent warming, with snow accumulation declining in West Antarctica and the eastern Ross Sea.
Pascal Bohleber, Tobias Erhardt, Nicole Spaulding, Helene Hoffmann, Hubertus Fischer, and Paul Mayewski
Clim. Past, 14, 21–37, https://doi.org/10.5194/cp-14-21-2018, https://doi.org/10.5194/cp-14-21-2018, 2018
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The Colle Gnifetti (CG) glacier is the only drilling site in the European Alps offering ice core records back to some 1000 years. We aim to fully exploit these unique long-term records by establishing a reliable long-term age scale and an improved ice core proxy interpretation for reconstructing temperature. Our findings reveal a site-specific temperature-related signal in the trends of the mineral dust proxy Ca2+ that may supplement other proxy evidence over the last millennium.
Niklas Boers, Mickael D. Chekroun, Honghu Liu, Dmitri Kondrashov, Denis-Didier Rousseau, Anders Svensson, Matthias Bigler, and Michael Ghil
Earth Syst. Dynam., 8, 1171–1190, https://doi.org/10.5194/esd-8-1171-2017, https://doi.org/10.5194/esd-8-1171-2017, 2017
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We use a Bayesian approach for inferring inverse, stochastic–dynamic models from northern Greenland (NGRIP) oxygen and dust records of subdecadal resolution for the interval 59 to 22 ka b2k. Our model reproduces the statistical and dynamical characteristics of the records, including the Dansgaard–Oeschger variability, with no need for external forcing. The crucial ingredients are cubic drift terms, nonlinear coupling terms between the oxygen and dust time series, and non-Markovian contributions.
Bette L. Otto-Bliesner, Pascale Braconnot, Sandy P. Harrison, Daniel J. Lunt, Ayako Abe-Ouchi, Samuel Albani, Patrick J. Bartlein, Emilie Capron, Anders E. Carlson, Andrea Dutton, Hubertus Fischer, Heiko Goelzer, Aline Govin, Alan Haywood, Fortunat Joos, Allegra N. LeGrande, William H. Lipscomb, Gerrit Lohmann, Natalie Mahowald, Christoph Nehrbass-Ahles, Francesco S. R. Pausata, Jean-Yves Peterschmitt, Steven J. Phipps, Hans Renssen, and Qiong Zhang
Geosci. Model Dev., 10, 3979–4003, https://doi.org/10.5194/gmd-10-3979-2017, https://doi.org/10.5194/gmd-10-3979-2017, 2017
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The PMIP4 and CMIP6 mid-Holocene and Last Interglacial simulations provide an opportunity to examine the impact of two different changes in insolation forcing on climate at times when other forcings were relatively similar to present. This will allow exploration of the role of feedbacks relevant to future projections. Evaluating these simulations using paleoenvironmental data will provide direct out-of-sample tests of the reliability of state-of-the-art models to simulate climate changes.
Frédéric Parrenin, Marie G. P. Cavitte, Donald D. Blankenship, Jérôme Chappellaz, Hubertus Fischer, Olivier Gagliardini, Valérie Masson-Delmotte, Olivier Passalacqua, Catherine Ritz, Jason Roberts, Martin J. Siegert, and Duncan A. Young
The Cryosphere, 11, 2427–2437, https://doi.org/10.5194/tc-11-2427-2017, https://doi.org/10.5194/tc-11-2427-2017, 2017
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The oldest dated deep ice core drilled in Antarctica has been retrieved at EPICA Dome C (EDC), reaching ~ 800 000 years. Obtaining an older palaeoclimatic record from Antarctica is one of the greatest challenges of the ice core community. Here, we estimate the age of basal ice in the Dome C area. We find that old ice (> 1.5 Myr) likely exists in two regions a few tens of kilometres away from EDC:
Little Dome C Patchand
North Patch.
Denis-Didier Rousseau, Anders Svensson, Matthias Bigler, Adriana Sima, Jorgen Peder Steffensen, and Niklas Boers
Clim. Past, 13, 1181–1197, https://doi.org/10.5194/cp-13-1181-2017, https://doi.org/10.5194/cp-13-1181-2017, 2017
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We show that the analysis of δ18O and dust in the Greenland ice cores, and a critical study of their source variations, reconciles these records with those observed on the Eurasian continent. We demonstrate the link between European and Chinese loess sequences, dust records in Greenland, and variations in the North Atlantic sea ice extent. The sources of the emitted and transported dust material are variable and relate to different environments.
Peter Köhler, Christoph Nehrbass-Ahles, Jochen Schmitt, Thomas F. Stocker, and Hubertus Fischer
Earth Syst. Sci. Data, 9, 363–387, https://doi.org/10.5194/essd-9-363-2017, https://doi.org/10.5194/essd-9-363-2017, 2017
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We document our best available data compilation of published ice core records of the greenhouse gases CO2, CH4, and N2O and recent measurements on firn air and atmospheric samples covering the time window from 156 000 years BP to the beginning of the year 2016 CE. A smoothing spline method is applied to translate the discrete and irregularly spaced data points into continuous time series. The radiative forcing for each greenhouse gas is computed using well-established, simple formulations.
Damiano Della Lunga, Wolfgang Müller, Sune Olander Rasmussen, Anders Svensson, and Paul Vallelonga
The Cryosphere, 11, 1297–1309, https://doi.org/10.5194/tc-11-1297-2017, https://doi.org/10.5194/tc-11-1297-2017, 2017
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In our study we combined the wealth of information provided by Greenland ice cores with an ultra-high-resolution technique well known in geoscience (laser ablation). Our set-up was developed and applied to investigate the variability in concentration of ions across a rapid climatic change from the oldest part of the last glaciation, showing that concentrations drop abruptly from cold to warm periods, representing a shift in atmospheric transport that happens even faster than previously thought.
Kathrin M. Keller, Sebastian Lienert, Anil Bozbiyik, Thomas F. Stocker, Olga V. Churakova (Sidorova), David C. Frank, Stefan Klesse, Charles D. Koven, Markus Leuenberger, William J. Riley, Matthias Saurer, Rolf Siegwolf, Rosemarie B. Weigt, and Fortunat Joos
Biogeosciences, 14, 2641–2673, https://doi.org/10.5194/bg-14-2641-2017, https://doi.org/10.5194/bg-14-2641-2017, 2017
Anne-Katrine Faber, Bo Møllesøe Vinther, Jesper Sjolte, and Rasmus Anker Pedersen
Atmos. Chem. Phys., 17, 5865–5876, https://doi.org/10.5194/acp-17-5865-2017, https://doi.org/10.5194/acp-17-5865-2017, 2017
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The recent decades loss of Arctic sea ice provide an interesting opportunity to study the impact of sea ice changes on the isotopic composition of Arctic precipitation. Using a climate model that can simulate water isotopes, we find that reduced sea ice extent yields more enriched isotope values while increased sea ice extent yields more
depleted isotope values. Results also show that the spatial distribution of the sea ice extent are important.
Grant M. Raisbeck, Alexandre Cauquoin, Jean Jouzel, Amaelle Landais, Jean-Robert Petit, Vladimir Y. Lipenkov, Juerg Beer, Hans-Arno Synal, Hans Oerter, Sigfus J. Johnsen, Jorgen P. Steffensen, Anders Svensson, and Françoise Yiou
Clim. Past, 13, 217–229, https://doi.org/10.5194/cp-13-217-2017, https://doi.org/10.5194/cp-13-217-2017, 2017
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Using records of a long-lived radioactive nuclide (10Be) that is formed globally in the atmosphere and deposited within a few years to the earth’s surface, we have synchronized three Antarctic ice cores to one from Greenland. This permits the climate and other environmental parameters registered in these ice cores to be put on a common timescale with a precision of a few decades, thus allowing different models and mechanisms associated with these parameters to be tested with the same precision.
Silvia Becagli, Fabrizio Anello, Carlo Bommarito, Federico Cassola, Giulia Calzolai, Tatiana Di Iorio, Alcide di Sarra, José-Luis Gómez-Amo, Franco Lucarelli, Miriam Marconi, Daniela Meloni, Francesco Monteleone, Silvia Nava, Giandomenico Pace, Mirko Severi, Damiano Massimiliano Sferlazzo, Rita Traversi, and Roberto Udisti
Atmos. Chem. Phys., 17, 2067–2084, https://doi.org/10.5194/acp-17-2067-2017, https://doi.org/10.5194/acp-17-2067-2017, 2017
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The paper aims to implement a specific strategy to target the aerosol due to ship emissions. PM10 is collected south and north of the main shipping route through the Mediterranean. Other than ions and metals the analysis is complemented with measurements of rare earth elements, trajectories from a high resolution regional model and actual observations of ship traffic. The combination of these approaches allows for unambiguous identification of the ship contribution (8–11 % of PM10) in this area.
Stefan Muthers, Christoph C. Raible, Eugene Rozanov, and Thomas F. Stocker
Earth Syst. Dynam., 7, 877–892, https://doi.org/10.5194/esd-7-877-2016, https://doi.org/10.5194/esd-7-877-2016, 2016
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The Atlantic Meridional Overturning Circulation (AMOC) is an important oceanic circulation system which transports large amounts of heat from the tropics to the north. This circulation is strengthened when less solar irradiance reaches the Earth, e.g. due to reduced solar activity or geoengineering techniques. In climate models, however, this response is overestimated when chemistry–climate interactions and the following shift in the atmospheric circulation systems are not considered.
Niklaus Merz, Andreas Born, Christoph C. Raible, and Thomas F. Stocker
Clim. Past, 12, 2011–2031, https://doi.org/10.5194/cp-12-2011-2016, https://doi.org/10.5194/cp-12-2011-2016, 2016
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The last (Eemian) interglacial is studied with a global climate model focusing on Greenland and the adjacent high latitudes. A set of model experiments demonstrates the crucial role of changes in sea ice and sea surface temperatures for the magnitude of Eemian atmospheric warming. Greenland temperatures are found highly sensitive to sea ice changes in the Nordic Seas but rather insensitive to changes in the Labrador Sea. This behavior has important implications for Greenland ice core signals.
Michel Legrand, Joseph McConnell, Hubertus Fischer, Eric W. Wolff, Susanne Preunkert, Monica Arienzo, Nathan Chellman, Daiana Leuenberger, Olivia Maselli, Philip Place, Michael Sigl, Simon Schüpbach, and Mike Flannigan
Clim. Past, 12, 2033–2059, https://doi.org/10.5194/cp-12-2033-2016, https://doi.org/10.5194/cp-12-2033-2016, 2016
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Here, we review previous attempts made to reconstruct past forest fire using chemical signals recorded in Greenland ice. We showed that the Greenland ice records of ammonium, found to be a good fire proxy, consistently indicate changing fire activity in Canada in response to past climatic conditions that occurred since the last 15 000 years, including the Little Ice Age and the last large climatic transition.
Morgane Philippe, Jean-Louis Tison, Karen Fjøsne, Bryn Hubbard, Helle A. Kjær, Jan T. M. Lenaerts, Reinhard Drews, Simon G. Sheldon, Kevin De Bondt, Philippe Claeys, and Frank Pattyn
The Cryosphere, 10, 2501–2516, https://doi.org/10.5194/tc-10-2501-2016, https://doi.org/10.5194/tc-10-2501-2016, 2016
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The reconstruction of past snow accumulation rates is crucial in the context of recent climate change and sea level rise. We measured ~ 250 years of snow accumulation using a 120 m ice core drilled in coastal East Antarctica, where such long records are very scarce. This study is the first to show an increase in snow accumulation, beginning in the 20th and particularly marked in the last 50 years, thereby confirming model predictions of increased snowfall associated with climate change.
Bette L. Otto-Bliesner, Pascale Braconnot, Sandy P. Harrison, Daniel J. Lunt, Ayako Abe-Ouchi, Samuel Albani, Patrick J. Bartlein, Emilie Capron, Anders E. Carlson, Andrea Dutton, Hubertus Fischer, Heiko Goelzer, Aline Govin, Alan Haywood, Fortunat Joos, Allegra N. Legrande, William H. Lipscomb, Gerrit Lohmann, Natalie Mahowald, Christoph Nehrbass-Ahles, Jean-Yves Peterschmidt, Francesco S.-R. Pausata, Steven Phipps, and Hans Renssen
Clim. Past Discuss., https://doi.org/10.5194/cp-2016-106, https://doi.org/10.5194/cp-2016-106, 2016
Preprint retracted
Olivier Eicher, Matthias Baumgartner, Adrian Schilt, Jochen Schmitt, Jakob Schwander, Thomas F. Stocker, and Hubertus Fischer
Clim. Past, 12, 1979–1993, https://doi.org/10.5194/cp-12-1979-2016, https://doi.org/10.5194/cp-12-1979-2016, 2016
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A new high-resolution total air content record over the NGRIP ice core, spanning 0.3–120 kyr is presented. In agreement with Antarctic ice cores, we find a strong local insolation signature but also 3–5 % decreases in total air content as a local response to Dansgaard–Oeschger events, which can only partly be explained by changes in surface pressure and temperature. Accordingly, a dynamic response of firnification to rapid climate changes on the Greenland ice sheet must have occurred.
Luca Ferrero, David Cappelletti, Maurizio Busetto, Mauro Mazzola, Angelo Lupi, Christian Lanconelli, Silvia Becagli, Rita Traversi, Laura Caiazzo, Fabio Giardi, Beatrice Moroni, Stefano Crocchianti, Martin Fierz, Griša Močnik, Giorgia Sangiorgi, Maria G. Perrone, Marion Maturilli, Vito Vitale, Roberto Udisti, and Ezio Bolzacchini
Atmos. Chem. Phys., 16, 12601–12629, https://doi.org/10.5194/acp-16-12601-2016, https://doi.org/10.5194/acp-16-12601-2016, 2016
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This study reports results from systematic vertical aerosol profiles measured in the Arctic using a tethered balloon platform. The collected data allowed for finding common rules of aerosol behavior along height and seasons. Transport events, secondary aerosol formation and ship impact are examples of the issues investigated along height. The importance of these issues is related to their climatic implications in reference to the aerosol direct and indirect effects in the Arctic atmosphere.
Amaelle Landais, Valérie Masson-Delmotte, Emilie Capron, Petra M. Langebroek, Pepijn Bakker, Emma J. Stone, Niklaus Merz, Christoph C. Raible, Hubertus Fischer, Anaïs Orsi, Frédéric Prié, Bo Vinther, and Dorthe Dahl-Jensen
Clim. Past, 12, 1933–1948, https://doi.org/10.5194/cp-12-1933-2016, https://doi.org/10.5194/cp-12-1933-2016, 2016
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The last lnterglacial (LIG; 116 000 to 129 000 years before present) surface temperature at the upstream Greenland NEEM deposition site is estimated to be warmer by +7 to +11 °C compared to the preindustrial period. We show that under such warm temperatures, melting of snow probably led to a significant surface melting. There is a paradox between the extent of the Greenland ice sheet during the LIG and the strong warming during this period that models cannot solve.
Thomas Röckmann, Simon Eyer, Carina van der Veen, Maria E. Popa, Béla Tuzson, Guillaume Monteil, Sander Houweling, Eliza Harris, Dominik Brunner, Hubertus Fischer, Giulia Zazzeri, David Lowry, Euan G. Nisbet, Willi A. Brand, Jaroslav M. Necki, Lukas Emmenegger, and Joachim Mohn
Atmos. Chem. Phys., 16, 10469–10487, https://doi.org/10.5194/acp-16-10469-2016, https://doi.org/10.5194/acp-16-10469-2016, 2016
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A dual isotope ratio mass spectrometric system (IRMS) and a quantum cascade laser absorption spectroscopy (QCLAS)-based technique were deployed at the Cabauw experimental site for atmospheric research (CESAR) in the Netherlands and performed in situ, high-frequency (approx. hourly) measurements for a period of more than 5 months, yielding a combined dataset with more than 2500 measurements of both δ13C and δD.
Basil Neff, Andreas Born, and Thomas F. Stocker
Earth Syst. Dynam., 7, 397–418, https://doi.org/10.5194/esd-7-397-2016, https://doi.org/10.5194/esd-7-397-2016, 2016
Fulvio Amato, Andrés Alastuey, Angeliki Karanasiou, Franco Lucarelli, Silvia Nava, Giulia Calzolai, Mirko Severi, Silvia Becagli, Vorne L. Gianelle, Cristina Colombi, Celia Alves, Danilo Custódio, Teresa Nunes, Mario Cerqueira, Casimiro Pio, Konstantinos Eleftheriadis, Evangelia Diapouli, Cristina Reche, María Cruz Minguillón, Manousos-Ioannis Manousakas, Thomas Maggos, Stergios Vratolis, Roy M. Harrison, and Xavier Querol
Atmos. Chem. Phys., 16, 3289–3309, https://doi.org/10.5194/acp-16-3289-2016, https://doi.org/10.5194/acp-16-3289-2016, 2016
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Harmonized source apportionment of atmospheric particulate matter (PM10 and PM2.5) at 5 EU cities (Barcelona, Florence, Milan, Athens and Porto) reveals that vehicle exhaust (excluding nitrate) plus non-exhaust contributes 16–32 % to PM10 and 15–36 % to PM2.5. Secondary PM represents 37–82 % of PM2.5. Biomass burning varies from < 2 to 24 % of PM10, depending on the residential heating fuel. Other sources are local dust (7–19 % of PM10), industries (4–11 % of PM10), shipping, sea salt and Saharan dust.
Thomas Goossens, Célia J. Sapart, Dorthe Dahl-Jensen, Trevor Popp, Saïda El Amri, and Jean-Louis Tison
The Cryosphere, 10, 553–567, https://doi.org/10.5194/tc-10-553-2016, https://doi.org/10.5194/tc-10-553-2016, 2016
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This first multi-parametric analysis of the basal ice layer of the NEEM ice core reveals that its formation does not result from a mixing process between local relict ice and the deepest ice layers of the advancing ice sheet during its growth phase. Instead, it is shown that the basal sequence partly originates from melting and refreezing processes acting at the ice/bedrock interface under a well-developed ice sheet. These have partially destroyed the paleoclimatic records of the ice.
S. Mailler, L. Menut, A. G. di Sarra, S. Becagli, T. Di Iorio, B. Bessagnet, R. Briant, P. Formenti, J.-F. Doussin, J. L. Gómez-Amo, M. Mallet, G. Rea, G. Siour, D. M. Sferlazzo, R. Traversi, R. Udisti, and S. Turquety
Atmos. Chem. Phys., 16, 1219–1244, https://doi.org/10.5194/acp-16-1219-2016, https://doi.org/10.5194/acp-16-1219-2016, 2016
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We studied the impact of aerosols on tropospheric photolysis rates at Lampedusa during the CharMEx/ADRIMED campaign in June 2013. It is shown by using the CHIMERE chemistry-transport model (CTM) as well as in situ and remote-sensing measurements that taking into account the radiative effect of the tropospheric aerosols improves the ability of the model to reproduce the observed photolysis rates. It is hence important for CTMs to include the radiative effect of aerosols on photochemistry.
S. Eyer, B. Tuzson, M. E. Popa, C. van der Veen, T. Röckmann, M. Rothe, W. A. Brand, R. Fisher, D. Lowry, E. G. Nisbet, M. S. Brennwald, E. Harris, C. Zellweger, L. Emmenegger, H. Fischer, and J. Mohn
Atmos. Meas. Tech., 9, 263–280, https://doi.org/10.5194/amt-9-263-2016, https://doi.org/10.5194/amt-9-263-2016, 2016
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We present a newly developed field-deployable, autonomous platform simultaneously measuring the three most abundant isotopologues of methane using mid-infrared laser absorption spectroscopy.
The instrument consists of a compact quantum cascade laser absorption spectrometer (QCLAS) coupled to a preconcentration unit, called TRace gas EXtractor (TREX).
The performance of this new in situ technique was investigated during a 2-week measurement campaign and compared to other techniques.
G. Calzolai, S. Nava, F. Lucarelli, M. Chiari, M. Giannoni, S. Becagli, R. Traversi, M. Marconi, D. Frosini, M. Severi, R. Udisti, A. di Sarra, G. Pace, D. Meloni, C. Bommarito, F. Monteleone, F. Anello, and D. M. Sferlazzo
Atmos. Chem. Phys., 15, 13939–13955, https://doi.org/10.5194/acp-15-13939-2015, https://doi.org/10.5194/acp-15-13939-2015, 2015
S. Fujita, F. Parrenin, M. Severi, H. Motoyama, and E. W. Wolff
Clim. Past, 11, 1395–1416, https://doi.org/10.5194/cp-11-1395-2015, https://doi.org/10.5194/cp-11-1395-2015, 2015
A. Svensson, S. Fujita, M. Bigler, M. Braun, R. Dallmayr, V. Gkinis, K. Goto-Azuma, M. Hirabayashi, K. Kawamura, S. Kipfstuhl, H. A. Kjær, T. Popp, M. Simonsen, J. P. Steffensen, P. Vallelonga, and B. M. Vinther
Clim. Past, 11, 1127–1137, https://doi.org/10.5194/cp-11-1127-2015, https://doi.org/10.5194/cp-11-1127-2015, 2015
G. van der Wel, H. Fischer, H. Oerter, H. Meyer, and H. A. J. Meijer
The Cryosphere, 9, 1601–1616, https://doi.org/10.5194/tc-9-1601-2015, https://doi.org/10.5194/tc-9-1601-2015, 2015
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The diffusion of the stable water isotope signal during firnification of snow is a temperature-dependent process. Therefore, past local temperatures can be derived from the differential diffusion length. In this paper we develop a new method for determining this quantity and compare it with the existing method. Both methods are applied to a large number of synthetic data sets to assess the precision and accuracy of the reconstruction and to a section of the Antarctic EDML ice core record.
J.-L. Tison, M. de Angelis, G. Littot, E. Wolff, H. Fischer, M. Hansson, M. Bigler, R. Udisti, A. Wegner, J. Jouzel, B. Stenni, S. Johnsen, V. Masson-Delmotte, A. Landais, V. Lipenkov, L. Loulergue, J.-M. Barnola, J.-R. Petit, B. Delmonte, G. Dreyfus, D. Dahl-Jensen, G. Durand, B. Bereiter, A. Schilt, R. Spahni, K. Pol, R. Lorrain, R. Souchez, and D. Samyn
The Cryosphere, 9, 1633–1648, https://doi.org/10.5194/tc-9-1633-2015, https://doi.org/10.5194/tc-9-1633-2015, 2015
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The oldest paleoclimatic information is buried within the lowermost layers of deep ice cores. It is therefore essential to judge how deep these records remain unaltered. We study the bottom 60 meters of the EPICA Dome C ice core from central Antarctica to show that the paleoclimatic signal is only affected at the small scale (decimeters) in terms of some of the global ice properties. However our data suggest that the time scale has been considerably distorted by mechanical stretching.
N. B. Karlsson and D. Dahl-Jensen
The Cryosphere, 9, 1465–1479, https://doi.org/10.5194/tc-9-1465-2015, https://doi.org/10.5194/tc-9-1465-2015, 2015
F. Lehner, F. Joos, C. C. Raible, J. Mignot, A. Born, K. M. Keller, and T. F. Stocker
Earth Syst. Dynam., 6, 411–434, https://doi.org/10.5194/esd-6-411-2015, https://doi.org/10.5194/esd-6-411-2015, 2015
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We present the first last-millennium simulation with the Community Earth System Model (CESM) including an interactive carbon cycle in both ocean and land component. Volcanic eruptions emerge as the strongest forcing factor for the preindustrial climate and carbon cycle. We estimate the climate-carbon-cycle feedback in CESM to be at the lower bounds of empirical estimates (1.3ppm/°C). The time of emergence for interannual global land and ocean carbon uptake rates are 1947 and 1877, respectively.
F. Parrenin, S. Fujita, A. Abe-Ouchi, K. Kawamura, V. Masson-Delmotte, H. Motoyama, F. Saito, M. Severi, B. Stenni, R. Uemura, and E. Wolff
Clim. Past Discuss., https://doi.org/10.5194/cpd-11-377-2015, https://doi.org/10.5194/cpd-11-377-2015, 2015
Revised manuscript has not been submitted
G. Gfeller, H. Fischer, M. Bigler, S. Schüpbach, D. Leuenberger, and O. Mini
The Cryosphere, 8, 1855–1870, https://doi.org/10.5194/tc-8-1855-2014, https://doi.org/10.5194/tc-8-1855-2014, 2014
A. Spolaor, P. Vallelonga, J. Gabrieli, T. Martma, M. P. Björkman, E. Isaksson, G. Cozzi, C. Turetta, H. A. Kjær, M. A. J. Curran, A. D. Moy, A. Schönhardt, A.-M. Blechschmidt, J. P. Burrows, J. M. C. Plane, and C. Barbante
Atmos. Chem. Phys., 14, 9613–9622, https://doi.org/10.5194/acp-14-9613-2014, https://doi.org/10.5194/acp-14-9613-2014, 2014
P. Vallelonga, K. Christianson, R. B. Alley, S. Anandakrishnan, J. E. M. Christian, D. Dahl-Jensen, V. Gkinis, C. Holme, R. W. Jacobel, N. B. Karlsson, B. A. Keisling, S. Kipfstuhl, H. A. Kjær, M. E. L. Kristensen, A. Muto, L. E. Peters, T. Popp, K. L. Riverman, A. M. Svensson, C. Tibuleac, B. M. Vinther, Y. Weng, and M. Winstrup
The Cryosphere, 8, 1275–1287, https://doi.org/10.5194/tc-8-1275-2014, https://doi.org/10.5194/tc-8-1275-2014, 2014
M. Bock, J. Schmitt, J. Beck, R. Schneider, and H. Fischer
Atmos. Meas. Tech., 7, 1999–2012, https://doi.org/10.5194/amt-7-1999-2014, https://doi.org/10.5194/amt-7-1999-2014, 2014
M. Montagnat, N. Azuma, D. Dahl-Jensen, J. Eichler, S. Fujita, F. Gillet-Chaulet, S. Kipfstuhl, D. Samyn, A. Svensson, and I. Weikusat
The Cryosphere, 8, 1129–1138, https://doi.org/10.5194/tc-8-1129-2014, https://doi.org/10.5194/tc-8-1129-2014, 2014
N. Merz, A. Born, C. C. Raible, H. Fischer, and T. F. Stocker
Clim. Past, 10, 1221–1238, https://doi.org/10.5194/cp-10-1221-2014, https://doi.org/10.5194/cp-10-1221-2014, 2014
M. Baumgartner, P. Kindler, O. Eicher, G. Floch, A. Schilt, J. Schwander, R. Spahni, E. Capron, J. Chappellaz, M. Leuenberger, H. Fischer, and T. F. Stocker
Clim. Past, 10, 903–920, https://doi.org/10.5194/cp-10-903-2014, https://doi.org/10.5194/cp-10-903-2014, 2014
M. Marconi, D. M. Sferlazzo, S. Becagli, C. Bommarito, G. Calzolai, M. Chiari, A. di Sarra, C. Ghedini, J. L. Gómez-Amo, F. Lucarelli, D. Meloni, F. Monteleone, S. Nava, G. Pace, S. Piacentino, F. Rugi, M. Severi, R. Traversi, and R. Udisti
Atmos. Chem. Phys., 14, 2039–2054, https://doi.org/10.5194/acp-14-2039-2014, https://doi.org/10.5194/acp-14-2039-2014, 2014
H. C. Steen-Larsen, V. Masson-Delmotte, M. Hirabayashi, R. Winkler, K. Satow, F. Prié, N. Bayou, E. Brun, K. M. Cuffey, D. Dahl-Jensen, M. Dumont, M. Guillevic, S. Kipfstuhl, A. Landais, T. Popp, C. Risi, K. Steffen, B. Stenni, and A. E. Sveinbjörnsdottír
Clim. Past, 10, 377–392, https://doi.org/10.5194/cp-10-377-2014, https://doi.org/10.5194/cp-10-377-2014, 2014
B. Bereiter, H. Fischer, J. Schwander, and T. F. Stocker
The Cryosphere, 8, 245–256, https://doi.org/10.5194/tc-8-245-2014, https://doi.org/10.5194/tc-8-245-2014, 2014
S. Schüpbach, U. Federer, P. R. Kaufmann, S. Albani, C. Barbante, T. F. Stocker, and H. Fischer
Clim. Past, 9, 2789–2807, https://doi.org/10.5194/cp-9-2789-2013, https://doi.org/10.5194/cp-9-2789-2013, 2013
S. O. Rasmussen, P. M. Abbott, T. Blunier, A. J. Bourne, E. Brook, S. L. Buchardt, C. Buizert, J. Chappellaz, H. B. Clausen, E. Cook, D. Dahl-Jensen, S. M. Davies, M. Guillevic, S. Kipfstuhl, T. Laepple, I. K. Seierstad, J. P. Severinghaus, J. P. Steffensen, C. Stowasser, A. Svensson, P. Vallelonga, B. M. Vinther, F. Wilhelms, and M. Winstrup
Clim. Past, 9, 2713–2730, https://doi.org/10.5194/cp-9-2713-2013, https://doi.org/10.5194/cp-9-2713-2013, 2013
R. Schneider, J. Schmitt, P. Köhler, F. Joos, and H. Fischer
Clim. Past, 9, 2507–2523, https://doi.org/10.5194/cp-9-2507-2013, https://doi.org/10.5194/cp-9-2507-2013, 2013
H. Fischer, J. Severinghaus, E. Brook, E. Wolff, M. Albert, O. Alemany, R. Arthern, C. Bentley, D. Blankenship, J. Chappellaz, T. Creyts, D. Dahl-Jensen, M. Dinn, M. Frezzotti, S. Fujita, H. Gallee, R. Hindmarsh, D. Hudspeth, G. Jugie, K. Kawamura, V. Lipenkov, H. Miller, R. Mulvaney, F. Parrenin, F. Pattyn, C. Ritz, J. Schwander, D. Steinhage, T. van Ommen, and F. Wilhelms
Clim. Past, 9, 2489–2505, https://doi.org/10.5194/cp-9-2489-2013, https://doi.org/10.5194/cp-9-2489-2013, 2013
N. Merz, C. C. Raible, H. Fischer, V. Varma, M. Prange, and T. F. Stocker
Clim. Past, 9, 2433–2450, https://doi.org/10.5194/cp-9-2433-2013, https://doi.org/10.5194/cp-9-2433-2013, 2013
J.-F. Lamarque, F. Dentener, J. McConnell, C.-U. Ro, M. Shaw, R. Vet, D. Bergmann, P. Cameron-Smith, S. Dalsoren, R. Doherty, G. Faluvegi, S. J. Ghan, B. Josse, Y. H. Lee, I. A. MacKenzie, D. Plummer, D. T. Shindell, R. B. Skeie, D. S. Stevenson, S. Strode, G. Zeng, M. Curran, D. Dahl-Jensen, S. Das, D. Fritzsche, and M. Nolan
Atmos. Chem. Phys., 13, 7997–8018, https://doi.org/10.5194/acp-13-7997-2013, https://doi.org/10.5194/acp-13-7997-2013, 2013
L. Bazin, A. Landais, B. Lemieux-Dudon, H. Toyé Mahamadou Kele, D. Veres, F. Parrenin, P. Martinerie, C. Ritz, E. Capron, V. Lipenkov, M.-F. Loutre, D. Raynaud, B. Vinther, A. Svensson, S. O. Rasmussen, M. Severi, T. Blunier, M. Leuenberger, H. Fischer, V. Masson-Delmotte, J. Chappellaz, and E. Wolff
Clim. Past, 9, 1715–1731, https://doi.org/10.5194/cp-9-1715-2013, https://doi.org/10.5194/cp-9-1715-2013, 2013
D. Veres, L. Bazin, A. Landais, H. Toyé Mahamadou Kele, B. Lemieux-Dudon, F. Parrenin, P. Martinerie, E. Blayo, T. Blunier, E. Capron, J. Chappellaz, S. O. Rasmussen, M. Severi, A. Svensson, B. Vinther, and E. W. Wolff
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H. C. Steen-Larsen, S. J. Johnsen, V. Masson-Delmotte, B. Stenni, C. Risi, H. Sodemann, D. Balslev-Clausen, T. Blunier, D. Dahl-Jensen, M. D. Ellehøj, S. Falourd, A. Grindsted, V. Gkinis, J. Jouzel, T. Popp, S. Sheldon, S. B. Simonsen, J. Sjolte, J. P. Steffensen, P. Sperlich, A. E. Sveinbjörnsdóttir, B. M. Vinther, and J. W. C. White
Atmos. Chem. Phys., 13, 4815–4828, https://doi.org/10.5194/acp-13-4815-2013, https://doi.org/10.5194/acp-13-4815-2013, 2013
S. Zürcher, R. Spahni, F. Joos, M. Steinacher, and H. Fischer
Biogeosciences, 10, 1963–1981, https://doi.org/10.5194/bg-10-1963-2013, https://doi.org/10.5194/bg-10-1963-2013, 2013
A. Svensson, M. Bigler, T. Blunier, H. B. Clausen, D. Dahl-Jensen, H. Fischer, S. Fujita, K. Goto-Azuma, S. J. Johnsen, K. Kawamura, S. Kipfstuhl, M. Kohno, F. Parrenin, T. Popp, S. O. Rasmussen, J. Schwander, I. Seierstad, M. Severi, J. P. Steffensen, R. Udisti, R. Uemura, P. Vallelonga, B. M. Vinther, A. Wegner, F. Wilhelms, and M. Winstrup
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A. Born, T. F. Stocker, and A. B. Sandø
Ocean Sci. Discuss., https://doi.org/10.5194/osd-10-555-2013, https://doi.org/10.5194/osd-10-555-2013, 2013
Revised manuscript not accepted
B. Bereiter, T. F. Stocker, and H. Fischer
Atmos. Meas. Tech., 6, 251–262, https://doi.org/10.5194/amt-6-251-2013, https://doi.org/10.5194/amt-6-251-2013, 2013
S. L. Buchardt, H. B. Clausen, B. M. Vinther, and D. Dahl-Jensen
Clim. Past, 8, 2053–2059, https://doi.org/10.5194/cp-8-2053-2012, https://doi.org/10.5194/cp-8-2053-2012, 2012
Related subject area
Subject: Atmospheric Dynamics | Archive: Ice Cores | Timescale: Millenial/D-O
Ice core evidence for decoupling between midlatitude atmospheric water cycle and Greenland temperature during the last deglaciation
Spatial gradients of temperature, accumulation and δ18O-ice in Greenland over a series of Dansgaard–Oeschger events
Annual layering in the NGRIP ice core during the Eemian
Potential analysis reveals changing number of climate states during the last 60 kyr
Amaëlle Landais, Emilie Capron, Valérie Masson-Delmotte, Samuel Toucanne, Rachael Rhodes, Trevor Popp, Bo Vinther, Bénédicte Minster, and Frédéric Prié
Clim. Past, 14, 1405–1415, https://doi.org/10.5194/cp-14-1405-2018, https://doi.org/10.5194/cp-14-1405-2018, 2018
Short summary
Short summary
During the last glacial–interglacial climate transition (120 000 to 10 000 years before present), Greenland climate and midlatitude North Atlantic climate and water cycle vary in phase over the succession of millennial events. We identify here one notable exception to this behavior with a decoupling unambiguously identified through a combination of water isotopic tracers measured in a Greenland ice core. The midlatitude moisture source becomes warmer and wetter at 16 200 years before present.
M. Guillevic, L. Bazin, A. Landais, P. Kindler, A. Orsi, V. Masson-Delmotte, T. Blunier, S. L. Buchardt, E. Capron, M. Leuenberger, P. Martinerie, F. Prié, and B. M. Vinther
Clim. Past, 9, 1029–1051, https://doi.org/10.5194/cp-9-1029-2013, https://doi.org/10.5194/cp-9-1029-2013, 2013
A. Svensson, M. Bigler, E. Kettner, D. Dahl-Jensen, S. Johnsen, S. Kipfstuhl, M. Nielsen, and J. P. Steffensen
Clim. Past, 7, 1427–1437, https://doi.org/10.5194/cp-7-1427-2011, https://doi.org/10.5194/cp-7-1427-2011, 2011
V. N. Livina, F. Kwasniok, and T. M. Lenton
Clim. Past, 6, 77–82, https://doi.org/10.5194/cp-6-77-2010, https://doi.org/10.5194/cp-6-77-2010, 2010
Short summary
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.
We employ acidity records from Greenland and Antarctic ice cores to estimate the emission...
