A5114374235- Geology and Paleoclimatology Research
- Paleontology and Stratigraphy of Fossils
- Methane Hydrates and Related Phenomena
- Geological and Geochemical Analysis
- Hydrocarbon exploration and reservoir analysis
- Geological and Geophysical Studies
- Marine and environmental studies
- Astro and Planetary Science
- earthquake and tectonic studies
- Marine Biology and Ecology Research
- Climate variability and models
- Geological Studies and Exploration
- Geological formations and processes
- Planetary Science and Exploration
- Geochemistry and Elemental Analysis
- Plant Diversity and Evolution
- Geochemistry and Geologic Mapping
- Evolution and Paleontology Studies
- Atmospheric and Environmental Gas Dynamics
- Marine and coastal ecosystems
- Arctic and Russian Policy Studies
- Geological and Geophysical Studies Worldwide
- Isotope Analysis in Ecology
- Geological Modeling and Analysis
- Space Exploration and Technology
Institut de physique du globe de Paris
2014-2024
Université Paris Cité
2013-2023
Centre National de la Recherche Scientifique
2006-2023
Sorbonne Paris Cité
2015-2017
Délégation Paris 7
2013
Laboratoire des Sciences du Climat et de l'Environnement
2006-2008
Université de Versailles Saint-Quentin-en-Yvelines
2008
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2006-2008
We review recent observations and models concerning the dynamics of Cryogenian global glaciation their biological consequences.
Research Article| May 01, 2011 Modeling the early Paleozoic long-term climatic trend Elise Nardin; Nardin † 1Laboratoire des Mécanismes et Transfert en Géologie, CNRS-UPS-IRD, Observatoire Midi-Pyrénées, Toulouse 31400, France †E-mail: elnardin@gmail.com Search for other works by this author on: GSW Google Scholar Yves Goddéris; Goddéris Yannick Donnadieu; Donnadieu 2Laboratoire Sciences du Climat de l'Environnement, CNRS-CEA, Gif-Sur-Yvette 91191, Guillaume Le Hir; Hir 3Université Paris...
Abstract The Ordovician glaciation represents the acme of one only three major icehouse periods in Earth's Phanerozoic history and is notorious for setting scene “big five” mass extinction events. Nevertheless, mechanisms that drove ice sheet growth remain poorly understood final extent crudely constrained. Here using an Earth system model with innovative coupling method between ocean, atmosphere, land accounting climate feedback processes, we report simulations portraying first time...
Neoproterozoic, and possibly Paleoproterozoic, glaciations represent the most extreme climate events in post‐Hadean Earth, may link closely with evolution of atmosphere life. According to Snowball Earth hypothesis, entire ocean was covered ice during these for a few million years, which time volcanic CO 2 increased enough cause deglaciation. Geochemical proxy data model calculations suggest that maximum 0.01–0.1 by volume, but early modeling suggested deglaciation not possible at = 0.2. We...
Abstract The rise of eukaryotes to ecological prominence represents one the most dramatic shifts in history Earth's biosphere. However, there is an enigmatic temporal lag between emergence eukaryotic organisms fossil record and their much later expansion. In parallel, evidence for a secular increase availability key macronutrient phosphorus (P) oceans. Here, we use Earth system model equipped with size‐structured marine ecosystem explore relationships plankton size, trophic complexity,...
Abstract. The Cenozoic inception and development of the Asian monsoons remain unclear have generated much debate, as several hypotheses regarding circulation patterns at work in Asia during Eocene been proposed few last decades. These include (a) existence modern-like since early Eocene; (b) that a weak South monsoon (SAM) little to no East (EAM); or (c) prevalence Intertropical Convergence Zone (ITCZ) migrations, also referred Indonesian–Australian (I-AM). As SAM EAM are supposed triggered...
Research Article| January 01, 2008 Scenario for the evolution of atmospheric pCO2 during a snowball Earth Guillaume Le Hir; Hir 1UMR CEA/CNRS/UVSQ, 1572 Laboratoire des Sciences du Climat et de l'Environnement, CE Saclay, Orme Merisiers, Bât. 701, 91191 Gif sur Yvette Cedex, France Search other works by this author on: GSW Google Scholar Gilles Ramstein; Ramstein Yannick Donnadieu; Donnadieu Yves Goddéris 2UMR CNRS, 5563 Mécanismes Transferts en Géologie, Observatoire Midi-Pyrénées, 14,...
Abstract. The Ordovician Period (485–443 Ma) is characterized by abundant evidence for continental-sized ice sheets. Modeling studies published so far require a sharp CO2 drawdown to initiate this glaciation. They mostly used non-dynamic slab mixed-layer ocean models. Here, we use general circulation model with coupled components ocean, atmosphere, and sea examine the response of climate changes in paleogeography. We conduct experiments wide range (from 16 2 times preindustrial atmospheric...
Abstract The Ordovician‐Silurian transition (∼455–430 Ma) is characterized by repeated climatic perturbations, concomitant with major changes in the global oceanic redox state best exemplified periodic deposition of black shales. relationship between evolution and cycles, however, remains largely debated. Here using an ocean‐atmosphere general circulation model accounting for ocean biogeochemistry (MITgcm), we investigate mechanisms responsible burial organic carbon immediately before,...
Usually overlooked orbital forcing unlocks persistent mismatch between model and paleobotanical data across the EOT.
Atmospheric circulation in a Snowball Earth is critical for determining cloud behavior, heat export from the tropics, regions of bare ice, and sea glacier flow. These processes strongly affect deglaciation ability oases to support photosynthetic marine life throughout Earth. Here we establish robust aspects atmospheric by running six general models with consistent boundary conditions. The produce qualitatively similar patterns precipitation minus evaporation. strength Hadley roughly double...
Abstract The Cryogenian Period (717–635 Ma) experienced two low‐latitude “snowball Earth” glaciations, the Sturtian and Marinoan of contrasting 57 <16 Myr durations, respectively. A lack reliable age controls on extensional tectonics associated magmatic rocks during has hampered an understanding deglaciation. Furthermore, although deglaciation is generally assumed to have occurred once ongoing magmatism accumulated enough atmospheric CO 2 , as suggested by cap carbonates, specific...
The body fossil and biomarker records hint at an increase in biotic complexity between the two Cryogenian Snowball Earth episodes (ca. 661 million to ≤650 years ago). Oxygen nutrient availability can promote complexity, but (particularly phosphorus) redox dynamics across this interval remain poorly understood. Here, we present high-resolution paleoredox phosphorus phase association data from multiple globally distributed drill core through non-glacial interval. These are first correlated...
The impact of the Siberian Traps emplacement led to extinction 90% marine species and 75% terrestrial species. Due 3-5 Mkm&#179; magma emitted over about 1Myr as determined by U-Pb dating. extensive volcanic activity released massive quantities gases into atmosphere, particularly carbon dioxide (CO2) sulfur (SO2). These emissions came from two main sources: magmatic resulting directly thermogenic produced intrusion magmas carbonate-rich, evaporite-rich, or organic matter-rich sediments...