Author
Peter W. Kubik
Other affiliations: Paul Scherrer Institute, École Polytechnique Fédérale de Lausanne
Bio: Peter W. Kubik is an academic researcher from ETH Zurich. The author has contributed to research in topics: Glacial period & Glacier. The author has an hindex of 68, co-authored 262 publications receiving 16373 citations. Previous affiliations of Peter W. Kubik include Paul Scherrer Institute & École Polytechnique Fédérale de Lausanne.
Papers published on a yearly basis
Papers
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TL;DR: Different 10Be ice core records from Greenland and Antarctica with the global 14C tree ring record using principal component analysis are combined to derive total solar irradiance, which is then used as a proxy of solar activity to identify the solar imprint in an Asian climate record.
Abstract: Understanding the temporal variation of cosmic radiation and solar activity during the Holocene is essential for studies of the solar-terrestrial relationship. Cosmic-ray produced radionuclides, such as 10Be and 14C which are stored in polar ice cores and tree rings, offer the unique opportunity to reconstruct the history of cosmic radiation and solar activity over many millennia. Although records from different archives basically agree, they also show some deviations during certain periods. So far most reconstructions were based on only one single radionuclide record, which makes detection and correction of these deviations impossible. Here we combine different 10Be ice core records from Greenland and Antarctica with the global 14C tree ring record using principal component analysis. This approach is only possible due to a new high-resolution 10Be record from Dronning Maud Land obtained within the European Project for Ice Coring in Antarctica in Antarctica. The new cosmic radiation record enables us to derive total solar irradiance, which is then used as a proxy of solar activity to identify the solar imprint in an Asian climate record. Though generally the agreement between solar forcing and Asian climate is good, there are also periods without any coherence, pointing to other forcings like volcanoes and greenhouse gases and their corresponding feedbacks. The newly derived records have the potential to improve our understanding of the solar dynamics and to quantify the solar influence on climate.
600 citations
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TL;DR: A range of complementary radionuclide proxies in sediments of the southernmost Atlantic Ocean over the past 140,000 years indicate that glacial periods were characterized by greatly increased fluxes of biogenic detritus out of surface waters.
Abstract: A range of complementary radionuclide proxies in sediments of the southernmost Atlantic Ocean over the past 140,000 years indicate that glacial periods were characterized by greatly increased fluxes of biogenic detritus out of surface waters. This increase in export production, which may have contributed to lower concentrations of carbon dioxide in the glacial atmosphere, was accompanied by more than a fivefold increase in accumulation of lithogenic iron transported by winds from Patagonian deserts. These observations support the hypothesis that the iron limitation of today's Southern Ocean productivity was relieved in glacial periods by a greater supply of iron from wind-blown dust.
516 citations
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University of Rhode Island1, Stockholm University2, Utrecht University3, Brown University4, United States Geological Survey5, Rice University6, University of Bordeaux7, Centre national de la recherche scientifique8, Yamagata University9, University College London10, Norwegian Polar Institute11, Boston University12, British Geological Survey13, University of Michigan14, Kyushu University15, National Oceanography Centre16, University of Aberdeen17, University of Padua18, Japan Agency for Marine-Earth Science and Technology19, James Madison University20, Nagoya University21, Tohoku University22, Hokkaido University23, Leibniz Institute of Marine Sciences24, Paul Scherrer Institute25, University of Bergen26
TL;DR: This record of the Neogene reveals cooling of the Arctic that was synchronous with the expansion of Greenland ice and East Antarctic ice and supporting arguments for bipolar symmetry in climate change.
Abstract: The history of the Arctic Ocean during the Cenozoic era (0–65 million years ago) is largely unknown from direct evidence. Here we present a Cenozoic palaeoceanographic record constructed from >400 m of sediment core from a recent drilling expedition to the Lomonosov ridge in the Arctic Ocean. Our record shows a palaeoenvironmental transition from a warm ‘greenhouse’ world, during the late Palaeocene and early Eocene epochs, to a colder ‘icehouse’ world influenced by sea ice and icebergs from the middle Eocene epoch to the present. For the most recent ~14 Myr, we find sedimentation rates of 1–2 cm per thousand years, in stark contrast to the substantially lower rates proposed in earlier studies; this record of the Neogene reveals cooling of the Arctic that was synchronous with the expansion of Greenland ice (~3.2 Myr ago) and East Antarctic ice (~14 Myr ago). We find evidence for the first occurrence of ice-rafted debris in the middle Eocene epoch (~45 Myr ago), some 35 Myr earlier than previously thought; fresh surface waters were present at ~49 Myr ago, before the onset of ice-rafted debris. Also, the temperatures of surface waters during the Palaeocene/Eocene thermal maximum (~55 Myr ago) appear to have been substantially warmer than previously estimated. The revised timing of the earliest Arctic cooling events coincides with those from Antarctica, supporting arguments for bipolar symmetry in climate change.
505 citations
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TL;DR: In the early Holocene, the Egesen stadial moraines can be divided into three or in some cases even more phases (sub-stadials) as mentioned in this paper.
406 citations
01 Jan 2008
TL;DR: In this article, the authors summarised the history of glacier advances in the European Alps between the last Eemian and the Holocene, between 30 and 18 ka, synchronous with the global ice volume maximum of Marine Isotope Stage (MIS) 2.
Abstract: Chronological data for glacier advances in the European Alps between the Last Interglacial (Eemian) and the Holocene are summarised (115 to 11 ka). During this time glaciers were most extensive, extending tens of kilometres out onto the forelands, between 30 and 18 ka, that is, synchronous with the global ice volume maximum of Marine Isotope Stage (MIS) 2. Evidence for ice expanding to just past the mountain front for an earlier major glacier advance comes from Swiss sites, where advances have been luminescence dated to MIS 5d (100 ka) and MIS 4 (70 ka). Up to now no such evidence has been found in the Eastern Alps. By 18 ka, more than 80% of the Late Wurmian ice volume had gone. Subsequently glaciers readvanced, reaching into the upper reaches of the main valleys during the Lateglacial Gschnitz stadial, which likely occurred around 17 ka, with final moraine stabilisation no later than 15.4 ka. The link of the Egesen stadial with the Younger Dryas climate deterioration is supported by exposure ages from four sites as well as minimum-limiting radiocarbon dates from bogs within former glacier tongue areas. Key questions on the spatial and temporal variability of ice extents throughout the last glacial cycle have yet to be answered. Copyright # 2008 John Wiley & Sons, Ltd.
359 citations
Cited by
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Queen's University Belfast1, Collège de France2, English Heritage3, University of Arizona4, University of Sheffield5, University of Oxford6, University of Minnesota7, University of Hohenheim8, University of Kiel9, Lawrence Livermore National Laboratory10, University of Bergen11, ETH Zurich12, University of Waikato13, Woods Hole Oceanographic Institution14, Swiss Federal Institute for Forest, Snow and Landscape Research15, Cornell University16, University of Bristol17, University of Glasgow18, University of California, Irvine19, University of New South Wales20
TL;DR: In this paper, Heaton, AG Hogg, KA Hughen, KF Kaiser, B Kromer, SW Manning, RW Reimer, DA Richards, JR Southon, S Talamo, CSM Turney, J van der Plicht, CE Weyhenmeyer
Abstract: Additional co-authors: TJ Heaton, AG Hogg, KA Hughen, KF Kaiser, B Kromer, SW Manning, RW Reimer, DA Richards, JR Southon, S Talamo, CSM Turney, J van der Plicht, CE Weyhenmeyer
13,605 citations
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TL;DR: A solar forcing mechanism therefore may underlie at least the Holocene segment of the North Atlantic's “1500-year” cycle, potentially providing an additional mechanism for amplifying the solar signals and transmitting them globally.
Abstract: Surface winds and surface ocean hydrography in the subpolar North Atlantic appear to have been influenced by variations in solar output through the entire Holocene. The evidence comes from a close correlation between inferred changes in production rates of the cosmogenic nuclides carbon-14 and beryllium-10 and centennial to millennial time scale changes in proxies of drift ice measured in deep-sea sediment cores. A solar forcing mechanism therefore may underlie at least the Holocene segment of the North Atlantic's "1500-year" cycle. The surface hydrographic changes may have affected production of North Atlantic Deep Water, potentially providing an additional mechanism for amplifying the solar signals and transmitting them globally.
2,938 citations
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Queen's University Belfast1, University of St Andrews2, Aix-Marseille University3, Historic England4, University of Sheffield5, University of Oxford6, Alfred Wegener Institute for Polar and Marine Research7, University of Minnesota8, Xi'an Jiaotong University9, Nanjing Normal University10, University of Hohenheim11, University of Kiel12, Lawrence Livermore National Laboratory13, University of California, Santa Cruz14, ETH Zurich15, University of Waikato16, Woods Hole Oceanographic Institution17, Heidelberg University18, Cornell University19, Lund University20, University of New South Wales21, University of Arizona22, University of Groningen23, University of Bristol24, University of Glasgow25, University of California, Irvine26, University of Bern27, Aarhus University28, Nagoya University29, Swiss Federal Institute for Forest, Snow and Landscape Research30, National Museum of Japanese History31, University of Bologna32
TL;DR: In this article, the international 14C calibration curves for both the Northern and Southern Hemispheres, as well as for the ocean surface layer, have been updated to include a wealth of new data and extended to 55,000 cal BP.
Abstract: Radiocarbon (14C) ages cannot provide absolutely dated chronologies for archaeological or paleoenvironmental studies directly but must be converted to calendar age equivalents using a calibration curve compensating for fluctuations in atmospheric 14C concentration. Although calibration curves are constructed from independently dated archives, they invariably require revision as new data become available and our understanding of the Earth system improves. In this volume the international 14C calibration curves for both the Northern and Southern Hemispheres, as well as for the ocean surface layer, have been updated to include a wealth of new data and extended to 55,000 cal BP. Based on tree rings, IntCal20 now extends as a fully atmospheric record to ca. 13,900 cal BP. For the older part of the timescale, IntCal20 comprises statistically integrated evidence from floating tree-ring chronologies, lacustrine and marine sediments, speleothems, and corals. We utilized improved evaluation of the timescales and location variable 14C offsets from the atmosphere (reservoir age, dead carbon fraction) for each dataset. New statistical methods have refined the structure of the calibration curves while maintaining a robust treatment of uncertainties in the 14C ages, the calendar ages and other corrections. The inclusion of modeled marine reservoir ages derived from a three-dimensional ocean circulation model has allowed us to apply more appropriate reservoir corrections to the marine 14C data rather than the previous use of constant regional offsets from the atmosphere. Here we provide an overview of the new and revised datasets and the associated methods used for the construction of the IntCal20 curve and explore potential regional offsets for tree-ring data. We discuss the main differences with respect to the previous calibration curve, IntCal13, and some of the implications for archaeology and geosciences ranging from the recent past to the time of the extinction of the Neanderthals.
2,800 citations
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TL;DR: The responses of the Northern and Southern Hemispheres differed significantly, which reveals how the evolution of specific ice sheets affected sea level and provides insight into how insolation controlled the deglaciation.
Abstract: We used 5704 14C, 10Be, and 3He ages that span the interval from 10,000 to 50,000 years ago (10 to 50 ka) to constrain the timing of the Last Glacial Maximum (LGM) in terms of global ice-sheet and mountain-glacier extent. Growth of the ice sheets to their maximum positions occurred between 33.0 and 26.5 ka in response to climate forcing from decreases in northern summer insolation, tropical Pacific sea surface temperatures, and atmospheric CO2. Nearly all ice sheets were at their LGM positions from 26.5 ka to 19 to 20 ka, corresponding to minima in these forcings. The onset of Northern Hemisphere deglaciation 19 to 20 ka was induced by an increase in northern summer insolation, providing the source for an abrupt rise in sea level. The onset of deglaciation of the West Antarctic Ice Sheet occurred between 14 and 15 ka, consistent with evidence that this was the primary source for an abrupt rise in sea level ~14.5 ka.
2,691 citations
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TL;DR: Studies of ecosystem processes on the Jornada Experimental Range in southern New Mexico suggest that longterm grazing of semiarid grasslands leads to an increase in the spatial and temporal heterogeneity of water, nitrogen, and other soil resources, which leads to the desertification of formerly productive land.
Abstract: Studies of ecosystem processes on the Jornada Experimental Range in southern New Mexico suggest that longterm grazing of semiarid grasslands leads to an increase in the spatial and temporal heterogeneity of water, nitrogen, and other soil resources. Heterogeneity of soil resources promotes invasion by desert shrubs, which leads to a further localization of soil resources under shrub canopies. In the barren area between shrubs, soil fertility is lost by erosion and gaseous emissions. This positive feedback leads to the desertification of formerly productive land in southern New Mexico and in other regions, such as the Sahel. Future desertification is likely to be exacerbated by global climate warming and to cause significant changes in global biogeochemical cycles.
2,376 citations