|
|
- Evidence for millennial-scale interactions between Hg cycling and
hydroclimate from Lake Bosumtwi, Ghana
Abstract: Evidence for millennial-scale interactions between Hg cycling and hydroclimate from Lake Bosumtwi, Ghana
Alice R. Paine, Joost Frieling, Timothy M. Shanahan, Tamsin A. Mather, Nicholas McKay, Stuart A. Robinson, David M. Pyle, Isabel M. Fendley, Ruth Kiely, and William D. Gosling
Clim. Past, 21, 817–839, https://doi.org/10.5194/cp-21-817-2025, 2025
Few tropical mercury (Hg) records extend beyond ~ 12 ka, meaning our current understanding of Hg behaviour may not fully account for the impact of long-term hydroclimate changes on the Hg cycle in these environments. Here, we present an ~ 96 kyr Hg record from Lake Bosumtwi, Ghana. A coupled response is observed between Hg flux and shifts in sediment composition reflective of changes in lake level, suggesting that hydroclimate may be a key driver of tropical Hg cycling over millennial timescales.
PubDate: Thu, 17 Apr 2025 17:43:11 +020
DOI: 10.5194/cp-21-817-2025 2025
- High-resolution Holocene record based on detailed tephrochronology from
Torfdalsvatn, north Iceland, reveals natural and anthropogenic impacts on
terrestrial and aquatic environments
Abstract: High-resolution Holocene record based on detailed tephrochronology from Torfdalsvatn, north Iceland, reveals natural and anthropogenic impacts on terrestrial and aquatic environments
David J. Harning, Christopher R. Florian, Áslaug Geirsdóttir, Thor Thordarson, Gifford H. Miller, Yarrow Axford, and Sædís Ólafsdóttir
Clim. Past, 21, 795–815, https://doi.org/10.5194/cp-21-795-2025, 2025
Questions remain about the past climate in Iceland, including the relative impacts of natural and human factors on vegetation change and soil erosion. We present a sub-centennial-scale record of landscape and algal productivity from a lake in north Iceland. Along with a high-resolution tephra age constraint that covers the last ∼ 12 000 years, our record provides an environmental template for the region and novel insight into the sensitivity of the Icelandic ecosystem to natural and human impacts.
PubDate: Fri, 11 Apr 2025 20:43:04 +020
DOI: 10.5194/cp-21-795-2025 2025
- Pattern scaling of simulated vegetation change in northern Africa during
glacial cycles
Abstract: Pattern scaling of simulated vegetation change in northern Africa during glacial cycles
Mateo Duque-Villegas, Martin Claussen, Thomas Kleinen, Jürgen Bader, and Christian H. Reick
Clim. Past, 21, 773–794, https://doi.org/10.5194/cp-21-773-2025, 2025
We simulate the last glacial cycle with a comprehensive model of the Earth system and investigate vegetation cover change in northern Africa during the last four African Humid Periods (AHPs). We find a common pattern of vegetation change and relate it with climatic factors in order to discuss how vegetation might have evolved during even older AHPs. This scaling relationship we find according to past AHPs fails to account for projected changes in northern Africa under strong greenhouse gas warming.
PubDate: Thu, 10 Apr 2025 20:43:04 +020
DOI: 10.5194/cp-21-773-2025 2025
- Environmental controls of rapid terrestrial organic matter mobilization to
the western Laptev Sea since the Last Deglaciation
Abstract: Environmental controls of rapid terrestrial organic matter mobilization to the western Laptev Sea since the Last Deglaciation
Tsai-Wen Lin, Tommaso Tesi, Jens Hefter, Hendrik Grotheer, Jutta Wollenburg, Florian Adolphi, Henning A. Bauch, Alessio Nogarotto, Juliane Müller, and Gesine Mollenhauer
Clim. Past, 21, 753–772, https://doi.org/10.5194/cp-21-753-2025, 2025
In order to understand the mechanisms governing permafrost organic matter remobilization, we investigated organic matter composition during past intervals of rapid sea-level rise, of inland warming, and of dense sea-ice cover in the Laptev Sea. We find that sea-level rise resulted in widespread erosion and transport of permafrost materials to the ocean but that erosion is mitigated by regional dense sea-ice cover. Factors like inland warming or floods increase permafrost mobilization locally.
PubDate: Fri, 04 Apr 2025 15:34:06 +020
DOI: 10.5194/cp-21-753-2025 2025
- Deglaciation and abrupt events in a coupled comprehensive
atmosphere–ocean–ice-sheet–solid-earth model
Abstract: Deglaciation and abrupt events in a coupled comprehensive atmosphere–ocean–ice-sheet–solid-earth model
Uwe Mikolajewicz, Marie-Luise Kapsch, Clemens Schannwell, Katharina D. Six, Florian A. Ziemen, Meike Bagge, Jean-Philippe Baudouin, Olga Erokhina, Veronika Gayler, Volker Klemann, Virna L. Meccia, Anne Mouchet, and Thomas Riddick
Clim. Past, 21, 719–751, https://doi.org/10.5194/cp-21-719-2025, 2025
A fully coupled atmosphere–ocean–ice-sheet–solid-earth model was applied to simulate the time from the Last Glacial Maximum (about 25 000 years before the present) to the pre-industrial period. The model simulations are compared to observational estimates. During this climate transition, the model simulates several abrupt changes in the North Atlantic region, which are initiated by different processes. The underlying mechanisms are analysed and described.
PubDate: Wed, 02 Apr 2025 12:51:33 +020
DOI: 10.5194/cp-21-719-2025 2025
- A question of time and space: a model approach to the synchronous
precipitation of gypsum and halite during the Messinian Salinity Crisis
Abstract: A question of time and space: a model approach to the synchronous precipitation of gypsum and halite during the Messinian Salinity Crisis
Ronja M. Ebner and Paul T. Meijer
Clim. Past, 21, 705–718, https://doi.org/10.5194/cp-21-705-2025, 2025
This work explores the spatial distribution of halite and gypsum within salt giants that formed in semi-enclosed basins via numerical box models. The results are compared to the Messinian salt giant, while our description of restrictions makes them transferable to other basins. As such, we propose a general timeline for precipitation patterns. Our results indicate that it is unlikely for gypsum and halite to precipitate simultaneously without additional internal restriction.
PubDate: Tue, 01 Apr 2025 12:51:33 +020
DOI: 10.5194/cp-21-705-2025 2025
- Contrasts in the marine inorganic carbon chemistry of the Benguela
Upwelling System since the Last Glacial Maximum
Abstract: Contrasts in the marine inorganic carbon chemistry of the Benguela Upwelling System since the Last Glacial Maximum
Szabina Karancz, Lennart J. de Nooijer, Bas van der Wagt, Marcel T. J. van der Meer, Sambuddha Misra, Rick Hennekam, Zeynep Erdem, Julie Lattaud, Negar Haghipour, Stefan Schouten, and Gert-Jan Reichart
Clim. Past, 21, 679–704, https://doi.org/10.5194/cp-21-679-2025, 2025
Changes in upwelling intensity of the Benguela upwelling region during the last glacial motivated us to investigate the local CO2 history during the last glacial-to-interglacial transition. Using various geochemical tracers on archives from both subsurface and surface waters reveals enhanced storage of carbon at depth during the Last Glacial Maximum. An efficient biological pump likely prevented outgassing of CO2 from intermediate depth to the atmosphere.
PubDate: Tue, 25 Mar 2025 19:36:45 +010
DOI: 10.5194/cp-21-679-2025 2025
- Reconstruction of Holocene and Last Interglacial vegetation dynamics and
wildfire activity in southern Siberia
Abstract: Reconstruction of Holocene and Last Interglacial vegetation dynamics and wildfire activity in southern Siberia
Jade Margerum, Julia Homann, Stuart Umbo, Gernot Nehrke, Thorsten Hoffmann, Anton Vaks, Aleksandr Kononov, Alexander Osintsev, Alena Giesche, Andrew Mason, Franziska A. Lechleitner, Gideon M. Henderson, Ola Kwiecien, and Sebastian F. M. Breitenbach
Clim. Past, 21, 661–677, https://doi.org/10.5194/cp-21-661-2025, 2025
We analyse a southern Siberian stalagmite to reconstruct soil respiration, wildfire, and vegetation trends during the Last Interglacial (LIG) (124.1–118.8 ka) and the Holocene (10–0 ka). Wildfires were more prevalent during the LIG than the Holocene and were supported by fire-prone species, low soil respiration, and a greater difference between summer and winter temperature. We show that vegetation type and summer/winter temperature contrast are strong drivers of Siberian wildfires.
PubDate: Thu, 20 Mar 2025 13:11:31 +010
DOI: 10.5194/cp-21-661-2025 2025
- Patterns of changing surface climate variability from the Last Glacial
Maximum to present in transient model simulations
Abstract: Patterns of changing surface climate variability from the Last Glacial Maximum to present in transient model simulations
Elisa Ziegler, Nils Weitzel, Jean-Philippe Baudouin, Marie-Luise Kapsch, Uwe Mikolajewicz, Lauren Gregoire, Ruza Ivanovic, Paul J. Valdes, Christian Wirths, and Kira Rehfeld
Clim. Past, 21, 627–659, https://doi.org/10.5194/cp-21-627-2025, 2025
During the Last Deglaciation, global surface temperature rose by about 4–7 °C over several millennia. We show that changes in year-to-year up to century-to-century fluctuations of temperature and precipitation during the Deglaciation were mostly larger than during either the preceding or succeeding more stable periods in 15 climate model simulations. The analysis demonstrates how ice sheets, meltwater, and volcanism influence simulated variability to inform future simulation protocols.
PubDate: Tue, 11 Mar 2025 21:37:53 +010
DOI: 10.5194/cp-21-627-2025 2025
- Multi-century mean summer temperature variations in the Southern Rhaetian
Alps reconstructed from Larix decidua blue intensity data
Abstract: Multi-century mean summer temperature variations in the Southern Rhaetian Alps reconstructed from Larix decidua blue intensity data
Riccardo Cerrato, Maria Cristina Salvatore, Michele Brunetti, Andrea Somma, and Carlo Baroni
Clim. Past, 21, 609–626, https://doi.org/10.5194/cp-21-609-2025, 2025
Understanding past climates requires data extending beyond modern instrumental records. This study shows that blue intensity (BI) measurements from European larch trees in the Southern Rhaetian Alps provide a stronger proxy for reconstructing past summer temperatures than traditional tree-ring-width data. BI processing enables regional-scale reconstructions and helps extend these reconstructions to the Mediterranean Basin and northern Europe, with excellent correlations to existing data.
PubDate: Mon, 10 Mar 2025 18:27:17 +010
DOI: 10.5194/cp-21-609-2025 2025
- Sediment fluxes dominate glacial–interglacial changes in ocean carbon
inventory: results from factorial simulations over the past 780 000
years
Abstract: Sediment fluxes dominate glacial–interglacial changes in ocean carbon inventory: results from factorial simulations over the past 780 000 years
Markus Adloff, Aurich Jeltsch-Thömmes, Frerk Pöppelmeier, Thomas F. Stocker, and Fortunat Joos
Clim. Past, 21, 571–592, https://doi.org/10.5194/cp-21-571-2025, 2025
We simulated how different processes affected the carbon cycle over the last eight glacial cycles. We found that the effects of interactive marine sediments enlarge the carbon fluxes that result from these processes, especially in the ocean, and alter various proxy signals. We provide an assessment of the directions of regional and global proxy changes that might be expected in response to different glacial–interglacial Earth system changes in the presence of interactive marine sediments.
PubDate: Fri, 28 Feb 2025 13:17:09 +010
DOI: 10.5194/cp-21-571-2025 2025
- Assessing the most severe subsistence crisis of the 18th century in the
northwest of the Iberian Peninsula: a climatological perspective
Abstract: Assessing the most severe subsistence crisis of the 18th century in the northwest of the Iberian Peninsula: a climatological perspective
Maite deCastro, José González-Cao, Nicolás G. deCastro, Juan J. Taboada, José M. Vaquero, and Moncho Gómez-Gesteira
Clim. Past, 21, 593–607, https://doi.org/10.5194/cp-21-593-2025, 2025
Persistent rains in the eastern Atlantic during 1768–1769 caused the worst agricultural crisis in Galicia and northern Portugal. Using the EKF400v2 paleo-reanalysis dataset, it was found that the rainfall anomaly was positive in 11 out of 12 months. June 1768 saw the highest positive rain anomaly of the century; September 1768 saw the second-highest. The atmospheric synoptic patterns show negative anomalies in sea level pressure and 500 hPa. These patterns induce surface low-pressure systems.
PubDate: Fri, 28 Feb 2025 13:17:09 +010
DOI: 10.5194/cp-21-593-2025 2025
- Public granaries as a source of proxy data on grain harvests and weather
extremes for historical climatology
Abstract: Public granaries as a source of proxy data on grain harvests and weather extremes for historical climatology
Rudolf Brázdil, Jan Lhoták, Kateřina Chromá, Dominik Collet, Petr Dobrovolný, and Heli Huhtamaa
Clim. Past, 21, 547–570, https://doi.org/10.5194/cp-21-547-2025, 2025
Public granaries served as key infrastructure to improve food security in agrarian societies. Granary data from 15 domains at the Sušice region (southwestern Bohemia) in the period 1789–1849 CE are used here to identify years with bad and good grain harvests, which have been further analysed using documentary data and climatic reconstructions. The data used represent a new source of proxy data for historical–climatological research.
PubDate: Tue, 25 Feb 2025 22:37:50 +010
DOI: 10.5194/cp-21-547-2025 2025
- Shifts in Greenland interannual climate variability lead
Dansgaard–Oeschger abrupt warming by hundreds of years
Abstract: Shifts in Greenland interannual climate variability lead Dansgaard–Oeschger abrupt warming by hundreds of years
Chloe A. Brashear, Tyler R. Jones, Valerie Morris, Bruce H. Vaughn, William H. G. Roberts, William B. Skorski, Abigail G. Hughes, Richard Nunn, Sune Olander Rasmussen, Kurt M. Cuffey, Bo M. Vinther, Todd Sowers, Christo Buizert, Vasileios Gkinis, Christian Holme, Mari F. Jensen, Sofia E. Kjellman, Petra M. Langebroek, Florian Mekhaldi, Kevin S. Rozmiarek, Jonathan W. Rheinlænder, Margit H. Simon, Giulia Sinnl, Silje Smith-Johnsen, and James W. C. White
Clim. Past, 21, 529–546, https://doi.org/10.5194/cp-21-529-2025, 2025
We use a series of spectral techniques to quantify the strength of high-frequency climate variability in northeastern Greenland to 50 000 ka before present. Importantly, we find that variability consistently decreases hundreds of years prior to Dansgaard–Oeschger warming events. Model simulations suggest a change in North Atlantic sea ice behavior contributed to this pattern, thus providing new information on the conditions which preceded abrupt climate change during the Last Glacial Period.
PubDate: Mon, 24 Feb 2025 22:37:50 +010
DOI: 10.5194/cp-21-529-2025 2025
- Total air content measurements from the RECAP ice core
Abstract: Total air content measurements from the RECAP ice core
Sindhu Vudayagiri, Bo Vinther, Johannes Freitag, Peter L. Langen, and Thomas Blunier
Clim. Past, 21, 517–528, https://doi.org/10.5194/cp-21-517-2025, 2025
Air trapped in polar ice during snowfall reflects atmospheric pressure at the time of occlusion, serving as a proxy for elevation. However, melting, firn structure changes, and air pressure variability complicate this relationship. We measured total air content (TAC) in the RECAP ice core from Renland ice cap, eastern Greenland, spanning 121 000 years. Melt layers and short-term TAC variations, whose origins remain unclear, present challenges in interpreting elevation changes.
PubDate: Wed, 19 Feb 2025 14:07:45 +010
DOI: 10.5194/cp-21-517-2025 2025
- Pollen-based climatic reconstructions for the interglacial analogues of
MIS 1 (MIS 19, 11, and 5) in the southwestern Mediterranean: insights from
ODP Site 976
Abstract: Pollen-based climatic reconstructions for the interglacial analogues of MIS 1 (MIS 19, 11, and 5) in the southwestern Mediterranean: insights from ODP Site 976
Dael Sassoon, Nathalie Combourieu-Nebout, Odile Peyron, Adele Bertini, Francesco Toti, Vincent Lebreton, and Marie-Hélène Moncel
Clim. Past, 21, 489–515, https://doi.org/10.5194/cp-21-489-2025, 2025
Climatic reconstructions of Marine Isotope Stages (MISs) 19, 11, and 5 and the current interglacial (MIS 1) based on pollen data from a marine core (Alboran Sea) show that, compared with MIS 1, MIS 19 was colder and highly variable, MIS 11 was longer and more stable, and MIS 5 was warmer. There is no real equivalent to the current interglacial, but past interglacials give insights into the sensitivity of the southwestern Mediterranean to global climatic changes in conditions similar to MIS 1.
PubDate: Tue, 18 Feb 2025 14:07:45 +010
DOI: 10.5194/cp-21-489-2025 2025
- New age constraints for glacial terminations IV, III, and III.a based on
western Mediterranean speleothem records
Abstract: New age constraints for glacial terminations IV, III, and III.a based on western Mediterranean speleothem records
Judit Torner, Isabel Cacho, Heather Stoll, Ana Moreno, Joan O. Grimalt, Francisco J. Sierro, Joan J. Fornós, Hai Cheng, and R. Lawrence Edwards
Clim. Past, 21, 465–487, https://doi.org/10.5194/cp-21-465-2025, 2025
We offer a clearer view of the timing of three relevant past glacial terminations. By analyzing the climatic signal recorded in stalagmite and linking it with marine records, we revealed differences in the intensity and duration of the ice melting associated with these three key deglaciations. This study shows that some deglaciations began earlier than previously thought; this improves our understanding of natural climate processes, helping us to contextualize current climate change.
PubDate: Fri, 14 Feb 2025 22:27:51 +010
DOI: 10.5194/cp-21-465-2025 2025
- Possible provenance of IRD by tracing late Eocene Antarctic iceberg
melting using a high-resolution ocean model
Abstract: Possible provenance of IRD by tracing late Eocene Antarctic iceberg melting using a high-resolution ocean model
Mark V. Elbertsen, Erik van Sebille, and Peter K. Bijl
Clim. Past, 21, 441–464, https://doi.org/10.5194/cp-21-441-2025, 2025
This work verifies the remarkable finds of late Eocene Antarctic-sourced iceberg-rafted debris on the South Orkney Microcontinent. We find that these icebergs must have been on the larger end of the size scale compared to today’s icebergs due to faster melting in the warmer Eocene climate. The study was performed using a high-resolution model in which individual icebergs were followed through time.
PubDate: Thu, 13 Feb 2025 18:06:15 +010
DOI: 10.5194/cp-21-441-2025 2025
- Assessment of the southern polar and subpolar warming in the PMIP4 last
interglacial simulations using paleoclimate data syntheses
Abstract: Assessment of the southern polar and subpolar warming in the PMIP4 last interglacial simulations using paleoclimate data syntheses
Qinggang Gao, Emilie Capron, Louise C. Sime, Rachael H. Rhodes, Rahul Sivankutty, Xu Zhang, Bette L. Otto-Bliesner, and Martin Werner
Clim. Past, 21, 419–440, https://doi.org/10.5194/cp-21-419-2025, 2025
Marine sediment and ice core records suggest a warmer Southern Ocean and Antarctica at the early last interglacial, ~127 000 years ago. However, when only forced by orbital parameters and greenhouse gas concentrations during that period, state-of-the-art climate models do not reproduce the magnitude of warming. Here we show that much of the warming at southern middle to high latitudes can be reproduced by a UK climate model, HadCM3, with a 3000-year freshwater forcing over the North Atlantic.
PubDate: Fri, 07 Feb 2025 13:24:54 +010
DOI: 10.5194/cp-21-419-2025 2025
- Impact of the Late Miocene Cooling on the loss of coral reefs in the
Central Indo-Pacific
Abstract: Impact of the Late Miocene Cooling on the loss of coral reefs in the Central Indo-Pacific
Benjamin F. Petrick, Lars Reuning, Miriam Pfeiffer, Gerald Auer, and Lorenz Schwark
Clim. Past, 21, 405–417, https://doi.org/10.5194/cp-21-405-2025, 2025
It is known that coral reefs were absent in the central Indo-Pacific during the Early Pliocene. This study uses a new temperature record based on TEX86H biomarkers from the Coral Sea between 11–2 Ma to show a 2 °C cooling in the central Indo-Pacific during the Late Miocene Cooling (7–5.4 Ma). This cooling triggered changes in terrestrial input, ocean circulation, and temperature. These multiple stressors could have caused reef collapses across the central Indo-Pacific.
PubDate: Fri, 07 Feb 2025 13:24:54 +010
DOI: 10.5194/cp-21-405-2025 2025
|
Open Access journal
