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R. S. W. van de Wal

Bio: R. S. W. van de Wal is an academic researcher from Utrecht University. The author has contributed to research in topics: Ice sheet & Greenland ice sheet. The author has an hindex of 50, co-authored 143 publications receiving 8927 citations.


Papers
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Journal ArticleDOI
Carlo Barbante1, J. M. Barnola1, J. M. Barnola2, Silvia Becagli1, J. Beer1, J. Beer3, M. Bigler1, Claude F. Boutron2, Claude F. Boutron1, Thomas Blunier1, E. Castellano1, Olivier Cattani, Jérôme Chappellaz1, Jérôme Chappellaz2, Dorthe Dahl-Jensen1, Maxime Debret2, Barbara Delmonte, D. Dick, S. Falourd, Sérgio H. Faria1, Urs Federer1, Hubertus Fischer, Johannes Freitag, Andreas Frenzel, Diedrich Fritzsche, Felix Fundel, Paolo Gabrielli2, Vania Gaspari, Rainer Gersonde, Wolfgang Graf, D. Grigoriev4, Ilka Hamann, Margareta Hansson, George R. Hoffmann, Hutterli5, Philippe Huybrechts, Elisabeth Isaksson6, Sigfus J Johnsen, Jean Jouzel, M. Kaczmarska6, Torbjörn Karlin, Patrik R Kaufmann, S. Kipfstuhl, Mika Kohno, Fabrice Lambert, Astrid Lambrecht, Amaelle Landais, Gunther Lawer, Markus Leuenberger, Geneviève C Littot5, L. Loulergue2, Dieter Lüthi, Valter Maggi, F. Marino, Valérie Masson-Delmotte, Hanno Meyer, Heinrich Miller, Robert Mulvaney5, Biancamaria Narcisi, Johannes Oerlemans, H. Oerter, Frédéric Parrenin2, J. R. Petit2, Grant M. Raisbeck, Dominique Raynaud2, Regine Röthlisberger5, U. Ruth, Oleg Rybak, Mirko Severi, Jochen Schmitt, Jakob Schwander, Urs Siegenthaler, M.-L. Siggaard-Andersen1, Renato Spahni, Jørgen Peder Steffensen1, Barbara Stenni7, Thomas F. Stocker, Jean-Louis Tison, Rita Traversi, Roberto Udisti, Fernando Valero-Delgado, M. R. van den Broeke, R. S. W. van de Wal, Dietmar Wagenbach, Anna Wegner, K. Weiler, Frank Wilhelms, Jan-Gunnar Winther6, Eric W. Wolff5 
09 Nov 2006-Nature
TL;DR: In this paper, a glacial climate record derived from an ice core from Dronning Maud Land, Antarctica, which represents South Atlantic climate at a resolution comparable with the Greenland ice core records was presented.
Abstract: Precise knowledge of the phase relationship between climate changes in the two hemispheres is a key for understanding the Earth's climate dynamics. For the last glacial period, ice core studies1, 2 have revealed strong coupling of the largest millennial-scale warm events in Antarctica with the longest Dansgaard–Oeschger events in Greenland3, 4, 5 through the Atlantic meridional overturning circulation6, 7, 8. It has been unclear, however, whether the shorter Dansgaard–Oeschger events have counterparts in the shorter and less prominent Antarctic temperature variations, and whether these events are linked by the same mechanism. Here we present a glacial climate record derived from an ice core from Dronning Maud Land, Antarctica, which represents South Atlantic climate at a resolution comparable with the Greenland ice core records. After methane synchronization with an ice core from North Greenland9, the oxygen isotope record from the Dronning Maud Land ice core shows a one-to-one coupling between all Antarctic warm events and Greenland Dansgaard–Oeschger events by the bipolar seesaw6. The amplitude of the Antarctic warm events is found to be linearly dependent on the duration of the concurrent stadial in the North, suggesting that they all result from a similar reduction in the meridional overturning circulation.

1,074 citations

Journal ArticleDOI
14 Aug 2008-Nature
TL;DR: The importance of ice dynamics and ice–climate interactions in establishing the 100,000-year glacial cycles is demonstrated, with enhanced North American ice-sheet growth and the subsequent merging of the ice sheets being key elements.
Abstract: The onset of major glaciations in the Northern Hemisphere about 2.7 million years ago was most probably induced by climate cooling during the late Pliocene epoch. These glaciations, during which the Northern Hemisphere ice sheets successively expanded and retreated, are superimposed on this long-term climate trend, and have been linked to variations in the Earth's orbital parameters. One intriguing problem associated with orbitally driven glacial cycles is the transition from 41,000-year to 100,000-year climatic cycles that occurred without an apparent change in insolation forcing. Several hypotheses have been proposed to explain the transition, both including and excluding ice-sheet dynamics. Difficulties in finding a conclusive answer to this palaeoclimatic problem are related to the lack of sufficiently long records of ice-sheet volume or sea level. Here we use a comprehensive ice-sheet model and a simple ocean-temperature model to extract three-million-year mutually consistent records of surface air temperature, ice volume and sea level from marine benthic oxygen isotopes. Although these records and their relative phasings are subject to considerable uncertainty owing to limited availability of palaeoclimate constraints, the results suggest that the gradual emergence of the 100,000-year cycles can be attributed to the increased ability of the merged North American ice sheets to survive insolation maxima and reach continental-scale size. The oversized, wet-based ice sheet probably responded to the subsequent insolation maximum by rapid thinning through increased basal-sliding, thereby initiating a glacial termination. Based on our assessment of the temporal changes in air temperature and ice volume during individual glacials, we demonstrate the importance of ice dynamics and ice-climate interactions in establishing the 100,000-year glacial cycles, with enhanced North American ice-sheet growth and the subsequent merging of the ice sheets being key elements.

396 citations

Journal ArticleDOI
TL;DR: In this article, dynamic ice-flow models for 12 glaciers and ice caps have been forced with various climate change scenarios, and the results indicate that few glaciers would survive until 2100.
Abstract: Dynamic ice-flow models for 12 glaciers and ice caps have been forced with various climate change scenarios The volume of this sample spans three orders of magnitude Six climate scenarios were considered: from 1990 onwards linear warming rates of 001, 002 and 004 K a-1, with and without concurrent changes in precipitation The models, calibrated against the historic record of glacier length where possible, were integrated until 2100 The differences in individual glacier responses are very large No straightforward relationship between glacier size and fractional change of ice volume emerges for any given climate scenario The hypsometry of individual glaciers and ice caps plays an important role in their response, thus making it difficult to generalize results For a warming rate of 004 K a-1, without increase in precipitation, results indicate that few glaciers would survive until 2100 On the other hand, if the warming rate were to be limited to 001 K a-1 with an increase in precipitation of 10% per degree warming, we predict that overall loss would be restricted to 10 to 20% of the 1990 volume

361 citations

Journal ArticleDOI
TL;DR: In this article, a database of surface Antarctic snow isotopic composition is constructed using available measurements, with an estimate of data quality and local variability, and the capacity of theoretical isotopic, regional, and general circulation atmospheric models to reproduce the observed features and assess the role of moisture advection in spatial deuterium excess fluctuations.
Abstract: A database of surface Antarctic snow isotopic composition is constructed using available measurements, with an estimate of data quality and local variability. Although more than 1000 locations are documented, the spatial coverage remains uneven with a majority of sites located in specific areas of East Antarctica. The database is used to analyze the spatial variations in snow isotopic composition with respect to geographical characteristics (elevation, distance to the coast) and climatic features (temperature, accumulation) and with a focus on deuterium excess. The capacity of theoretical isotopic, regional, and general circulation atmospheric models (including “isotopic” models) to reproduce the observed features and assess the role of moisture advection in spatial deuterium excess fluctuations is analyzed.

351 citations

Journal ArticleDOI
04 Jul 2008-Science
TL;DR: Continuous Global Positioning System observations reveal rapid and large ice velocity fluctuations in the western ablation zone of the Greenland Ice Sheet, which suggests that the englacial hydraulic system adjusts constantly to the variable meltwater input, which results in a more or less constant ice flux over the years.
Abstract: Continuous Global Positioning System observations reveal rapid and large ice velocity fluctuations in the western ablation zone of the Greenland Ice Sheet. Within days, ice velocity reacts to increased meltwater production and increases by a factor of 4. Such a response is much stronger and much faster than previously reported. Over a longer period of 17 years, annual ice velocities have decreased slightly, which suggests that the englacial hydraulic system adjusts constantly to the variable meltwater input, which results in a more or less constant ice flux over the years. The positive-feedback mechanism between melt rate and ice velocity appears to be a seasonal process that may have only a limited effect on the response of the ice sheet to climate warming over the next decades.

325 citations


Cited by
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Journal Article
TL;DR: In this paper, a documento: "Cambiamenti climatici 2007: impatti, adattamento e vulnerabilita" voteato ad aprile 2007 dal secondo gruppo di lavoro del Comitato Intergovernativo sui Cambiamentsi Climatici (Intergovernmental Panel on Climate Change).
Abstract: Impatti, adattamento e vulnerabilita Le cause e le responsabilita dei cambiamenti climatici sono state trattate sul numero di ottobre della rivista Cda. Approfondiamo l’argomento presentando il documento: “Cambiamenti climatici 2007: impatti, adattamento e vulnerabilita” votato ad aprile 2007 dal secondo gruppo di lavoro del Comitato Intergovernativo sui Cambiamenti Climatici (Intergovernmental Panel on Climate Change). Si tratta del secondo di tre documenti che compongono il quarto rapporto sui cambiamenti climatici.

3,979 citations

Journal ArticleDOI
07 Aug 2009-Science
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

Journal ArticleDOI
TL;DR: A forum to review, analyze and stimulate the development, testing and implementation of mitigation and adaptation strategies at regional, national and global scales as mentioned in this paper, which contributes to real-time policy analysis and development as national and international policies and agreements are discussed.
Abstract: ▶ Addresses a wide range of timely environment, economic and energy topics ▶ A forum to review, analyze and stimulate the development, testing and implementation of mitigation and adaptation strategies at regional, national and global scales ▶ Contributes to real-time policy analysis and development as national and international policies and agreements are discussed and promulgated ▶ 94% of authors who answered a survey reported that they would definitely publish or probably publish in the journal again

2,587 citations

Journal ArticleDOI
24 Apr 2009-Science
TL;DR: What is known and what is needed to develop a holistic understanding of the role of fire in the Earth system are reviewed, particularly in view of the pervasive impact of fires and the likelihood that they will become increasingly difficult to control as climate changes.
Abstract: Fire is a worldwide phenomenon that appears in the geological record soon after the appearance of terrestrial plants. Fire influences global ecosystem patterns and processes, including vegetation distribution and structure, the carbon cycle, and climate. Although humans and fire have always coexisted, our capacity to manage fire remains imperfect and may become more difficult in the future as climate change alters fire regimes. This risk is difficult to assess, however, because fires are still poorly represented in global models. Here, we discuss some of the most important issues involved in developing a better understanding of the role of fire in the Earth system.

2,365 citations

Book Chapter
01 Jan 2013
TL;DR: The authors assesses long-term projections of climate change for the end of the 21st century and beyond, where the forced signal depends on the scenario and is typically larger than the internal variability of the climate system.
Abstract: This chapter assesses long-term projections of climate change for the end of the 21st century and beyond, where the forced signal depends on the scenario and is typically larger than the internal variability of the climate system. Changes are expressed with respect to a baseline period of 1986-2005, unless otherwise stated.

2,253 citations