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1. Millennial climatic fluctuations are key to the structure of last glacial ecosystems.

Author

Brian Huntley, Judy R M Allen, Yvonne C Collingham, Thomas Hickler, Adrian M Lister, Joy Singarayer, Anthony J Stuart, Martin T Sykes, and Paul J Valdes

Subjects
Medicine, Science
Abstract

Whereas fossil evidence indicates extensive treeless vegetation and diverse grazing megafauna in Europe and northern Asia during the last glacial, experiments combining vegetation models and climate models have to-date simulated widespread persistence of trees. Resolving this conflict is key to understanding both last glacial ecosystems and extinction of most of the mega-herbivores. Using a dynamic vegetation model (DVM) we explored the implications of the differing climatic conditions generated by a general circulation model (GCM) in "normal" and "hosing" experiments. Whilst the former approximate interstadial conditions, the latter, designed to mimic Heinrich Events, approximate stadial conditions. The "hosing" experiments gave simulated European vegetation much closer in composition to that inferred from fossil evidence than did the "normal" experiments. Given the short duration of interstadials, and the rate at which forest cover expanded during the late-glacial and early Holocene, our results demonstrate the importance of millennial variability in determining the character of last glacial ecosystems.

Published
2013
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2. Terrestrial biosphere changes over the last 120 kyr

Author

Mark B. Bush, Jemma M. Finch, Laura Sadori, Trevor Hill, Shonil A. Bhagwat, Ulrich C Müller, Sandy P. Harrison, Takeshi Nakagawa, Babette A A Hoogakker, A. de Vernal, Judy R M Allen, Merna McKenzie, Gonzalo Jiménez-Moreno, Dan Penny, C. Tzedakis, Hermann Behling, Bianca Fréchette, Olga K. Borisova, M. Vandergoes, Brian Huntley, Alexander Correa-Metrio, Iain Colin Prentice, Peter Kershaw, Jennifer A. Hanselman, Wojciech Granoszewski, Eberhard Grüger, Joy S. Singarayer, Eric C. Grimm, Paul J. Valdes, Rob Marchant, Louis Scott, R. S. Anderson, Donatella Magri, A.A. Velichko, Janelle Stevenson, Cathy Whitlock, M.-P. Ledru, Elena Novenko, Robin S. Smith, William D. Gosling, Socorro Lozano-García, Fischer, H., Paleoecology and Landscape Ecology (IBED, FNWI), Department of Earth Sciences [Oxford], University of Oxford [Oxford], University of Reading (UOR), Bristol Research Initiative for the Dynamic Global Environment (BRIDGE), School of Geographical Sciences [Bristol], University of Bristol [Bristol]-University of Bristol [Bristol], University of York [York, UK], Grantham Institute for Climate Change and the Environment, Imperial College London, Department of Life Sciences, Department of Biological Sciences [North Ryde], Macquarie University, Durham University, Northern Arizona University [Flagstaff], The Open University [Milton Keynes] (OU), Georg-August-University [Göttingen], Institute of Geography of RAS, Russian Academy of Sciences [Moscow] (RAS), Florida Institute of Technology [Melbourne], Universidad Nacional Autónoma de México (UNAM), Centre de recherche sur la dynamique du système Terre (GEOTOP), Université de Montréal (UdeM)-McGill University = Université McGill [Montréal, Canada]-École Polytechnique de Montréal (EPM)-Concordia University [Montreal]-Université du Québec à Rimouski (UQAR)-Université du Québec à Montréal = University of Québec in Montréal (UQAM)-Université du Québec en Abitibi-Témiscamingue (UQAT), University of KwaZulu-Natal (UKZN), Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam [Amsterdam] (UvA), Polish Geological Institute, National Research Institute, Illinois State Museum, Centre for Past Climate Change (CPCC), School of Archaeology, Geography and Environmental Sciences (SAGES), Universidad de Granada (UGR), Monash University [Melbourne], Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UR226, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Monash University [Clayton], Biodiversity and Climate Research Centre (BiK-F) (LOEWE), Institute of Geosciences [Frankfurt am Main], Goethe-Universität Frankfurt am Main, Ritsumeikan University, EarthByte Group, School of Geosciences, The University of Sydney, University of the Free State [South Africa], Australian National University (ANU), Climate Change Institute [Orono] (CCI), University of Maine, Department of Earth Sciences [MSU Bozeman], Montana State University (MSU), Department of Geography, University College of London [London] (UCL), University of Oxford, Georg-August-University = Georg-August-Universität Göttingen, Universidad Nacional Autónoma de México = National Autonomous University of Mexico (UNAM), École Polytechnique de Montréal (EPM)-McGill University = Université McGill [Montréal, Canada]-Université de Montréal (UdeM)-Université du Québec en Abitibi-Témiscamingue (UQAT)-Université du Québec à Rimouski (UQAR)-Concordia University [Montreal]-Université du Québec à Montréal = University of Québec in Montréal (UQAM), University of KwaZulu-Natal [Durban, Afrique du Sud] (UKZN), Universidad de Granada = University of Granada (UGR), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), and University of the Free State [South Africa] (UFS)

Subjects
010506 paleontology, Terrestrial biosphere changes, 010504 meteorology & atmospheric sciences, lcsh:Environmental protection, POLLEN-BASED RECONSTRUCTIONS, Biome, global and planetary change, C-14 YR BP, 01 natural sciences, lcsh:Environmental pollution, PRETORIA SALTPAN, ddc:550, Meteorology & Atmospheric Sciences, ATMOSPHERIC CARBON-DIOXIDE, lcsh:TD169-171.8, GLACIAL-MAXIMUM, Geosciences, Multidisciplinary, lcsh:Environmental sciences, 0105 earth and related environmental sciences, lcsh:GE1-350, Carbon dioxide in Earth's atmosphere, Science & Technology, LATE-PLEISTOCENE, Biosphere, Temperate forest, Primary production, stratigraphy, Last Glacial Maximum, Geology, 15. Life on land, Tundra, MILLENNIAL-SCALE VARIABILITY, 13. Climate action, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, lcsh:TD172-193.5, Physical Sciences, Terrestrial ecosystem, Physical geography, [SDV.EE.BIO]Life Sciences [q-bio]/Ecology, environment/Bioclimatology, VEGETATION RECORDS, paleontology, PLANT MACROFOSSIL DATA, RAPID CLIMATE-CHANGE, 0406 Physical Geography And Environmental Geoscience
Abstract

A new global synthesis and biomization of long (> 40 kyr) pollen-data records is presented and used with simulations from the HadCM3 and FAMOUS climate models and the BIOME4 vegetation model to analyse the dynamics of the global terrestrial biosphere and carbon storage over the last glacial–interglacial cycle. Simulated biome distributions using BIOME4 driven by HadCM3 and FAMOUS at the global scale over time generally agree well with those inferred from pollen data. Global average areas of grassland and dry shrubland, desert, and tundra biomes show large-scale increases during the Last Glacial Maximum, between ca. 64 and 74 ka BP and cool substages of Marine Isotope Stage 5, at the expense of the tropical forest, warm-temperate forest, and temperate forest biomes. These changes are reflected in BIOME4 simulations of global net primary productivity, showing good agreement between the two models. Such changes are likely to affect terrestrial carbon storage, which in turn influences the stable carbon isotopic composition of seawater as terrestrial carbon is depleted in 13C.

Published
2016
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3. Climate changes in the central Mediterranean and Italian vegetation dynamics since the Pliocene

Author

Fabio Fusco, Vincent Lebreton, Nathalie Combourieu-Nebout, Stefan Klotz, Ronan Orain, Séverine Fauquette, Vincent Montade, Sébastien Joannin, Simon Goring, Odile Peyron, Donatella Magri, Adele Bertini, Judy R M Allen, Laura Sadori, Brian Huntley, Elda Russo-Ermolli, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Dipartimento di Scienze della Terra [Firenze] (DST), Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), Institut de minéralogie et de physique des milieux condensés (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Centre National de la Recherche Scientifique (CNRS)-Institut de recherche pour le développement [IRD] : UMR237-Aix Marseille Université (AMU)-Avignon Université (AU), University of Westminster [London] (UOW), Department of Biological Sciences [Burnaby], Simon Fraser University (SFU.ca), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Centre de Bio-Archéologie et d'Ecologie (CBAE), Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Montpellier 2 - Sciences et Techniques (UM2), Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique (CNRS), Institut de Paléontologie Humaine (IPH), Centre National de la Recherche Scientifique (CNRS)-Fondation I.P.H, Histoire naturelle de l'Homme préhistorique (HNHP), Muséum national d'Histoire naturelle (MNHN)-Université de Perpignan Via Domitia (UPVD)-Centre National de la Recherche Scientifique (CNRS), Department of Vegetation Biology, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Firenze = University of Florence (UniFI), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement [IRD] : UMR237-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Université Montpellier 2 - Sciences et Techniques (UM2)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École Pratique des Hautes Études (EPHE), Fondation I.P.H-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] ( LSCE ), Université de Versailles Saint-Quentin-en-Yvelines ( UVSQ ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Centre National de la Recherche Scientifique ( CNRS ), Dipartimento di Scienze della Terra [Firenze] ( DST ), Università degli Studi di Firenze [Firenze], Laboratoire Chrono-environnement ( LCE ), Université Bourgogne Franche-Comté ( UBFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Institut de minéralogie et de physique des milieux condensés ( IMPMC ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -IPG PARIS-Université Paris Diderot - Paris 7 ( UPD7 ) -Centre National de la Recherche Scientifique ( CNRS ), Institut Méditerranéen d'Ecologie et de Paléoécologie ( IMEP ), Université Paul Cézanne - Aix-Marseille 3-Université de Provence - Aix-Marseille 1-Université d'Avignon et des Pays de Vaucluse ( UAPV ) -Centre National de la Recherche Scientifique ( CNRS ), University of Westminster [London] ( UOW ), Simon Fraser University ( SFU.ca ), Institut de Paléontologie Humaine ( IPH ), Fondation I.P.H-Centre National de la Recherche Scientifique ( CNRS ), Università degli Studi di Roma 'La Sapienza' [Rome], Combourieu Nebout, Nathalie, Bertini, Adèle, RUSSO ERMOLLI, Elda, Peyron, Odile, Klotz, Stefan, Montade, Vincent, Fauquette, Severine, Allen, Judy, Fusco, Fabio, Goring, Simon, Huntley, Brian, Joannin, Sébastien, Lebreton, Vincent, Magri, Donatella, Martinetto, Edoardo, Orain, Ronan, and Sadori, Laura

Subjects
Mediterranean climate, [ SDU.OCEAN ] Sciences of the Universe [physics]/Ocean, Atmosphere, Early Pleistocene, Pleistocene, Climate change, pliocene, Mediterranean Basin, central Mediterranean, vegetation, evolution, [ SDU.ENVI ] Sciences of the Universe [physics]/Continental interfaces, environment, Glacial period, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, climate, palynology, Ecology, Evolution, Behavior and Systematics, Holocene, ComputingMilieux_MISCELLANEOUS, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, quaternary, Ecology, 15. Life on land, behavior and systematics, 13. Climate action, Interglacial, paleontology, ecology, evolution, behavior and systematics, Physical geography, ecology, Geology
Abstract

Pollen records and pollen-based climate reconstructions from the Italian peninsula (central Mediterranean) show clear signals of vegetation change linked to variations in water availability in the Mediterranean basin over the past 5 million years. Profound vegetation changes occurred in four major steps from the Pliocene to the present. The subtropical taxa that dominate Pliocene assemblages declined and then disappeared between 3–2.8 and 1.66 Ma (at around 2.8 Ma in the North and later in the South), progressively being replaced by temperate Quercus forests at mid altitude. In the south Italy, Quercus expanded more at around 1.4–1.3 Ma and Fagus proportions increased after 0.5 Ma. Conifer forest (first mainly composed of Tsuga then by Abies and Picea) began to expand at 2.8 Ma, probably rather at high altitude, beginning at 2.8 Ma. Mediterranean-type forest, rare during the Early Pleistocene, developed and increased in diversity during the Middle Pleistocene. Open landscapes, with higher abundances of steppic taxa, became more frequent and extensive at the onset of Glacial/Interglacial (G/I) cyclicity around 2.6 Ma and gradually expanded with more and more marked glacials. Climate reconstructions done on selected pollen records from southern Italy suggest a decline in winter temperature and annual precipitation from the early Pleistocene to the Holocene. Specifically, both precipitation and winter temperature reconstructions show changes in interglacial maxima and glacial minima at around 3–2.8 Ma, 2 Ma, 1.3–1.4 Ma and 0.5 Ma. This critical review provides evidence that the North–South precipitation gradient, with drier conditions in the South, has been a consistent feature of the Italian peninsula since the beginning of the Pleistocene.

Published
2015
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4. Millennial climatic fluctuations are key to the structure of last glacial ecosystems

Author

Thomas Hickler, Adrian M. Lister, Paul J. Valdes, Brian Huntley, Judy R M Allen, Joy S. Singarayer, Martin T. Sykes, Yvonne C. Collingham, and Anthony J. Stuart

Subjects
010506 paleontology, 010504 meteorology & atmospheric sciences, Climate, Science, Vertebrate Paleontology, Social and Behavioral Sciences, 01 natural sciences, Ecosystems, Megafauna, Paleoclimatology, Geoinformatics, ddc:550, Ice Cover, Stadial, Glacial period, Terrestrial Ecology, Environmental Systems Modeling, Biology, Holocene, Ecosystem, Species Extinction, 0105 earth and related environmental sciences, Multidisciplinary, Ecology, Geography, Paleontology, Vegetation, 15. Life on land, 13. Climate action, Paleoecology, Earth Sciences, Medicine, Climate model, Physical geography, Ecosystem Modeling, Geology, Research Article
Abstract

Whereas fossil evidence indicates extensive treeless vegetation and diverse grazing megafauna in Europe and northern Asia during the last glacial, experiments combining vegetation models and climate models have to-date simulated widespread persistence of trees. Resolving this conflict is key to understanding both last glacial ecosystems and extinction of most of the mega-herbivores. Using a dynamic vegetation model (DVM) we explored the implications of the differing climatic conditions generated by a general circulation model (GCM) in “normal” and “hosing” experiments. Whilst the former approximate interstadial conditions, the latter, designed to mimic Heinrich Events, approximate stadial conditions. The “hosing” experiments gave simulated European vegetation much closer in composition to that inferred from fossil evidence than did the “normal” experiments. Given the short duration of interstadials, and the rate at which forest cover expanded during the late-glacial and early Holocene, our results demonstrate the importance of millennial variability in determining the character of last glacial ecosystems.

Published
2013

5. The past ecology of Abies alba provides new perspectives on future responses of silver fir forests to global warming

Author

André F. Lotter, Johanna Untenecker, Judy R M Allen, Marco Steinacher, Fortunat Joos, O. M. Heiri, Jürg Luterbacher, Verushka Valsecchi, Paul D. Henne, Danielle Colombaroli, Willy Tinner, Stéphanie Samartin, Elisa Vescovi, Gabrielle Carraro, Marco Conedera, Coastal dynamics, Fluvial systems and Global change, Palaeoecology, Sub Palaeoecology begr. 01-01-12, Palaeo-ecologie, and Dep Biologie

Subjects
0106 biological sciences, 010504 meteorology & atmospheric sciences, Range (biology), 530 Physics, 580 Plants (Botany), 010603 evolutionary biology, 01 natural sciences, paleoecology, climate models, Realized niche width, 910 Geography & travel, Ilex aquifolium, Ecology, Evolution, Behavior and Systematics, 550 Earth sciences & geology, bioclimatic envelope models, global change, 0105 earth and related environmental sciences, biology, Ecology, climatic niche, paleoclimatology, Macrofossil, Vegetation, 15. Life on land, biology.organism_classification, Abies alba, Geography, Disturbance (ecology), realized niche, 13. Climate action, Paleoecology, dynamic vegetation models
Abstract

Paleoecology can provide valuable insights into the ecology of species that complement observation and experiment-based assessments of climate impact dynamics. New paleoecological records (e.g., pollen, macrofossils) from the Italian Peninsula suggest a much wider climatic niche of the important European tree species Abies alba (silver fir) than observed in its present spatial range. To explore this discrepancy between current and past distribution of the species, we analyzed climatic data (temperature, precipitation, frost, humidity, sunshine) and vegetation-independent paleoclimatic reconstructions (e.g., lake levels, chironomids) and use global coupled carbon-cycle climate (NCAR CSM1.4) and dynamic vegetation (LandClim) modeling. The combined evidence suggests that during the mid-Holocene (;6000 years ago), prior to humanization of vegetation, A. alba formed forests under conditions that exceeded the modern (1961–1990) upper temperature limit of the species by ;5–78C (July means). Annual precipitation during this natural period was comparable to today (.700–800 mm), with drier summers and wetter winters. In the meso-Mediterranean to sub-Mediterranean forests A. alba co-occurred with thermophilous taxa such as Quercus ilex, Q. pubescens, Olea europaea, Phillyrea, Arbutus, Cistus, Tilia, Ulmus, Acer, Hedera helix, Ilex aquifolium, Taxus, and Vitis. Results from the last interglacial (ca. 130 000–115 000 BP), when human impact was negligible, corroborate the Holocene evidence. Thermophilous Mediterranean A. alba stands became extinct during the last 5000 years when land-use pressure and specifically excessive anthropogenic fire and browsing disturbance increased. Our results imply that the ecology of this key European tree species is not yet well understood. On the basis of the reconstructed realized climatic niche of the species, we anticipate that the future geographic range of A. alba may not contract regardless of migration success, even if climate should become significantly warmer than today with summer temperatures increasing by up to 5–78C, as long as precipitation does not fall below 700–800 mm/yr, and anthropogenic disturbance (e.g., fire, browsing) does not become excessive. Our finding contradicts recent studies that projected range contractions under global-warming scenarios, but did not factor how millennia of human impacts reduced the realized climatic niche of A. alba.

Published
2013
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6. Millennial-scale variability during the last glacial in vegetation records from Europe

Author

Filipa Naughton, Polychronis C Tzedakis, Brian Huntley, William J. Fletcher, Laurent Londeix, Katy Roucoux, Ulrich C Müller, Rachid Cheddadi, Maria Fernanda Sanchez Goñi, Judy R M Allen, Nathalie Combourieu-Nebout, Donatella Magri, Vasiliki Margari, Elena Novenko, Ian T. Lawson, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, 010506 paleontology, Archeology, Global and Planetary Change, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Taiga, Temperate forest, Geology, Vegetation, 15. Life on land, 01 natural sciences, Tundra, Grassland, Geography, Oceanography, Ice core, Continental margin, 13. Climate action, Glacial period, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Ecology, Evolution, Behavior and Systematics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences
Abstract

This paper evaluates the evidence for millennial-scale variability in pollen records of the last glacial (Marine Isotope Stages 4, 3, and 2; 73.5–14.7 calendar ka BP) from the European continent, taking into account information derived from long, continuous terrestrial records, the fragmentary northern European terrestrial record, and marine pollen records of the European continental margins. Pollen records from these numerous European sites provide evidence for multiple intervals of relatively warm and humid conditions during the last glacial, which promoted the establishment of grassland and shrub tundra in northwestern Europe, shrub- and forest-tundra in northeastern Europe, open boreal forest in central western Europe and the Alpine region, and open temperate forest in southern Europe. The northern limit for temperate forest development during these intervals was at ∼45°N, with a subsequent northward transition to tundra across a latitudinal band of ∼15° in western and central Europe, and a greater northward extension of boreal forest in eastern Europe, with boreal forest elements detected close to their present-day limits at ∼70°N. A much smaller number of sites with sufficiently high temporal resolution provide evidence that warming intervals correspond to millennial-scale variability as recorded in Greenland ice cores. A synthesis of sites providing high-resolution terrestrial and marine records from Europe is undertaken in order to examine geographical and temporal patterns in the expression of Dansgaard–Oeschger (D–O) cycles in the European vegetation. Detailed comparison of temperate forest development at these sites during four specific D–O cycles (D–O 16–17, 14, 12 and 8) reveals contrasts between vegetation response at southernmost European latitudes (below 40°N) and at latitudes above 40°N. At southernmost latitudes, marked forest development occurred during all four D–O cycles including D–O 16–17 and 8, while at latitudes above 40°N, forest development was stronger during D–O 14 and 12 than either D–O 16–17 or 8.

Published
2010
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7. The 'oriental' component of the Balkan flora: evidence of presence on the Thracian Plain during the Weichselian late-glacial

Author

Enikő Magyari, T. Deli, J. P. Huntley, Bisserka Gaydarska, John Chapman, Brian Huntley, Judy R M Allen, and Elena Marinova

Subjects
Steppe, postglacial recolonization, Older Dryas, leaf essential oils, Allerød oscillation, irano-pontic, juniperus excelsa, Paleontology, late weichselian, southern europe, celtis tournefortii-type, thracian plain, chloroplast dna variation, Stadial, Glacial period, plant macrofossils, Ecology, Evolution, Behavior and Systematics, Holocene, geography, northwest greece, geography.geographical_feature_category, Ecology, quaternary vegetational history, Macrofossil, pirin mountains, Vegetation, weichselian late-glacial, pollen analysis, southwestern bulgaria, scandes mountains, Geology, early holocene
Abstract

Aim: To obtain palaeobotanical evidence enabling evaluation of the viability of the hypothesis that the ‘oriental’ element of the Balkan flora reached south-east Europe from Turkey prior to the Holocene, probably via the Thracian Plain during a late Quaternary glacial stage but no later than the late Weichselian. Location: Ezero wetland, northern Thracian Plain, Bulgaria. Methods: We undertook analyses of pollen and microspores, plant macrofossils, wood fragments and molluscs recovered from sediments deposited in the Ezero wetland during the late Weichselian and Weichselian late-glacial. Sediment chronology was determined using radiocarbon age estimates. Results: Six metres of sediments were recovered from the basin, of which the lower 3 m, extending from c. 15,450 cal yr bp to the early Allerod, was analysed. A major hiatus occurred after c. 13,900 cal yr bp, the overlying sediments being of late Holocene age. Palaeobotanical evidence indicates predominantly open vegetation during the Weichselian late-glacial, although macrofossil remains of woody taxa demonstrate the local presence of patches of wooded steppe and gallery forest. Changes in the composition of the steppe vegetation, and in the nature of the sediments deposited in the basin, indicate changes in climatic conditions, especially in the hydrological regime and in the moisture available to vegetation. After an initially relatively moister phase, the final centuries of the late Weichselian were drier, as was a short interval that may correlate with the Older Dryas. Moister conditions characterize intervals corresponding to the Bolling and Allerod sub-units of the Weichselian late-glacial interstadial. Although the pollen evidence is thus consistent with that from previous studies of this period in south-east Europe and south-west Asia, indicating predominantly open steppe vegetation, the macrofossil evidence indicates the persistent local presence of woody taxa. The woody taxa recorded include Celtis tournefortii-type and Juniperus cf. J. excelsa, two taxa today characteristic of the wooded steppes of Anatolia and members of the ‘oriental’ element of the southern Balkan flora, as well as Rosaceae Subfams. Maloideae and Prunoideae, Alnus and Fraxinus. Main conclusions: The late Weichselian vegetation of the northern Thracian Plain included patches of wooded steppe that supported members of the ‘oriental’ element of the modern Balkan flora. The presence of such taxa renders viable the hypothesis that they could have reached south-east Europe from Turkey via the Thracian Plain during glacial times. Such hypotheses in historical biogeography can be evaluated critically using the evidence obtained from plant macrofossil analyses in combination with that from pollen analysis.

Published
2008
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8. Decadal-to-millennial-scale climate variability—chronology and mechanisms: summary and recommendations

Author

Carlo Laj, Michael Sarnthein, Rengaswamy Ramesh, Judy R M Allen, James P. Kennett, Jerry F. McManus, Pieter Meiert Grootes, Juerg Beer, Institut für Geowissenschaften [Kiel], Christian-Albrechts-Universität zu Kiel (CAU), University of California [Santa Barbara] (UC Santa Barbara), University of California (UC), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Climat et Magnétisme (CLIMAG), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Woods Hole Oceanographic Institution (WHOI), University of California [Santa Barbara] (UCSB), University of California, Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Archeology, Global and Planetary Change, 010504 meteorology & atmospheric sciences, Scale (ratio), Geology, 010502 geochemistry & geophysics, 01 natural sciences, 13. Climate action, Climatology, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Ecology, Evolution, Behavior and Systematics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Chronology
Abstract

International audience

Published
2002
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