Didier M. Roche

Learn More
The Last Glacial Maximum climate is one of the classical benchmarks used both to test the ability of coupled models to simulate climates different from that of the present-day and to better understand the possible range of mechanisms that could be involved in future climate change. It also bears the advantage of being one of the most well documented periods(More)
Oxygen isotope analysis of benthic foraminifera in deep sea cores from the Atlantic and Southern Oceans shows that during the last interglacial period, North Atlantic Deep Water (NADW) was 0.4 degrees +/- 0.2 degrees C warmer than today, whereas Antarctic Bottom Water temperatures were unchanged. Model simulations show that this distribution of deep water(More)
We use a state-of-the-art ocean general circulation and biogeochemistry model to examine the impact of changes in ocean circulation and biogeochemistry in governing the change in ocean carbon-13 and atmospheric CO2 at the last glacial maximum (LGM). We examine 5 different realisations of the ocean’s overturning circulation produced by a fully coupled(More)
Impact of brine-induced stratification on the glacial carbon cycle N. Bouttes, D. Paillard, and D. M. Roche Laboratoire des Sciences du Climat et de l’Environnement, IPSL-CEA-CNRS-UVSQ, UMR 8212, Centre d’Etudes de Saclay, Orme des Merisiers bat. 701, 91191 Gif Sur Yvette, France Faculty of Earth and Life Sciences, Section Climate Change and Landscape(More)
[1] The lack of climatic imprint left by the Meltwater Pulse-1A (’14.5 ka BP), equivalent to a sea-level rise of 14 to 20 meters, is puzzling. Recent studies suggest the event might have occurred as a hyperpycnal flow in the Gulf of Mexico, preventing its detection in oceanic records throughout the North Atlantic. We present a suite of simulations with the(More)
We quantify the agreement between permafrost distributions from PMIP2 (Paleoclimate Modeling Intercomparison Project) climate models and permafrost data. We evaluate the ability of several climate models to represent permafrost and assess the variability between their results. Studying a heterogeneous variable such as permafrost implies conducting analysis(More)
N. Bouttes1,2, D. M. Roche1,3, and D. Paillard1 1Laboratoire des Sciences du Climat et de l’Environnement, UMR8212, IPSL-CEA-CNRS-UVSQ – Centre d’Etudes de Saclay, Orme des Merisiers bat. 701, 91191 Gif Sur Yvette, France 2NCAS-Climate, Meteorology Department, University of Reading, Reading, RG66BB, UK 3Faculty of Earth and Life Sciences, Section Climate(More)
The first comparative and systematic climate model study of the sensitivity of the climate response under Last Glacial Maximum (LGM) conditions to freshwater perturbations at various locations that are known to have received significant amounts of freshwater during the LGM (21 kyr BP) climate conditions is presented. A series of ten regions representative(More)
The Asian summer monsoon dynamics at the orbital scale are a subject of considerable debate. The validity of Asian speleothem δ(18)O records as a proxy for summer monsoon intensity is questioned together with the ultimate forcing and timing of the monsoon. Here, using the results of a 150,000-year transient simulation including water isotopes, we(More)
Climate of the last glacial maximum: sensitivity studies and model-data comparison with the LOVECLIM coupled model D. M. Roche, T. M. Dokken, H. Goosse, H. Renssen, and S. L. Weber Department of Palaeoclimatology and Geomorphology, Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands(More)