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Anthony Boccaletti Jean Schneider Wes Traub Pierre-Olivier Lagage Daphne Stam Raffaele Gratton John Trauger Kerri Cahoy Frans Snik Pierre Baudoz Raphael Galicher Jean-Michel Reess Dimitri Mawet Jean-Charles Augereau Jenny Patience Marc Kuchner Mark Wyatt Eric Pantin Anne-Lise Maire Christophe Vérinaud Samuel Ronayette Didier Dubreuil Michiel Min Michiel Rodenhuis Dino Mesa Russ Belikov Olivier Guyon Motohide Tamura Naoshi Murakami Ingrid Mary Beerer 《Experimental Astronomy》2012,34(2):355-384
SPICES (Spectro-Polarimetric Imaging and Characterization of Exoplanetary Systems) is a five-year M-class mission proposed to ESA Cosmic Vision. Its purpose is to image and characterize long-period extrasolar planets and circumstellar disks in the visible (450?C900 nm) at a spectral resolution of about 40 using both spectroscopy and polarimetry. By 2020/2022, present and near-term instruments will have found several tens of planets that SPICES will be able to observe and study in detail. Equipped with a 1.5 m telescope, SPICES can preferentially access exoplanets located at several AUs (0.5?C10?AU) from nearby stars (<25 pc) with masses ranging from a few Jupiter masses to Super Earths (??2 Earth radii, ??10 M??) as well as circumstellar disks as faint as a few times the zodiacal light in the Solar System. 相似文献
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Jean-Charles Poilvet Marc Poujol Pavel Pitra Jean Van Den Driessche Jean-Louis Paquette 《Comptes Rendus Geoscience》2011,343(7):454-461
Dating the magmatism in the Montagne Noire gneiss dome in the southern French Massif Central is a key point for understanding the Late Palaeozoic evolution of this part of the Variscan belt, which is characterised by compressive tectonics during the Carboniferous and extensional tectonics during Stephanian-Permian times. The Montalet granite crops out in the north-western part of the dome and was first considered as an early syntectonic intrusion related to compressive deformation. More recently, it has been dated at 327 Ma and considered as contemporaneous with the diapiric ascent of the Montagne Noire gneiss dome before the Stephanian-Permian extension. We show that in fact, this pluton was emplaced 294 ± 1 Ma ago and is therefore contemporaneous with the Stephanian-Permian extension. This age is consistent with the interpretation of the Montagne Noire Massif as an extensional gneiss dome. 相似文献
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Poujol Marc Pitra Pavel Van Den Driessche Jean Tartèse Romain Ruffet Gilles Paquette Jean-Louis Poilvet Jean-Charles 《International Journal of Earth Sciences》2017,106(2):477-500
International Journal of Earth Sciences - One of the striking features that characterise the late stages of the Variscan orogeny is the development of gneiss and migmatite domes, as well as... 相似文献
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Haberkorn H Tran D Massabuau JC Ciret P Savar V Soudant P 《Marine pollution bulletin》2011,62(6):1191-1197
The complexity of the relationships between Alexandrium minutum (A.m.) concentration in the water ([A.m.]w), Paralytic Shellfish Poisoning contamination in the digestive gland ([PSP]dg) and valve behavior was explored in oysters Crassostrea gigas. Two experiments were conducted, during which oysters’ valve behaviour were analyzed. Oysters, first acclimated for 10-days with the non harmful microalgae Heterocapsa triquetra (H.t.), were exposed to four microalgae mixtures at constant total concentrations of 10 × 103 cells ml−1 (experiment-1) and 5 × 103 cells ml−1 (experiment-2): 100% A.m.; 50% A.m.-50% H.t.; 25% A.m.-75% H.t.; 100% H.t. At the end of experiment-2, [PSP]dg were measured.At 10 × 103 cells ml−1, the microalgal ingestion decreased (p < 0.05) with increasing [A.m.]w but not at 5 × 103 cells ml−1 (p > 0.05). The frequency of microclosures specifically increased with [A.m.]w (p < 0.05) and the opening duration with [PSP]dg (p < 0.0001). Oysters exhibiting the maximum increase in opening duration also exhibited the highest [PSP]dg. The results are discussed in terms of oyster physiology and origin of the behavioral response. 相似文献
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An assessment of the post-Kyoto climate change negotiations, and the altered role of climate finance post-financial crisis, is presented. First, the paradigm shift of the Cancun Agreements is examined from an historical perspective and it is shown that the impasse in the negotiations, caused by the underlying over-emphasis on burden sharing reductions in emissions, can be overcome. Second, using information from two modelling exercises, it is demonstrated how climate finance can encourage the decoupling of carbon emissions from economic growth and thereby help align the development pattern with global climate goals. Third, a framework to place carbon finance within current discussions is sketched regarding both the reformation of the world financial systems and the facilitation of a sustainable economic recovery that is beneficial for North and South while addressing the low-carbon transition. It is concluded that upgrading climate finance is the key to triggering the shift to a low-carbon society and a system is proposed in which an agreed social cost of carbon is used to support the establishment of carbon emissions certificates to reorient a significant portion of global savings towards low-carbon investments. Policy relevance Investments that align development and climate objectives are shown to substantially lower the social cost of carbon and deliver long-term carbon emissions reductions. These reductions are greater than those contributed by the sole carbon price signal generated by a world cap-and-trade system. Carbon finance, as a part of the broader reform of financial systems and overseas aid, can help overcome the dual adversity of climate and financial crisis contexts. The carbon certificate, with an upfront agreed social cost of carbon, can be used as its instrument. The portion of the banking system that intends to reorient a significant part of world savings towards low-carbon investments could thus issue such carbon certificates. By giving carbon assets the status of a reserve currency, the system could even respond to the need of emerging countries to diversify their foreign exchange reserves and trigger a wave of worldwide sustainable growth through infrastructure markets. 相似文献
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Predictability of the Meteorological Conditions Favourable to Radiative Fog Formation During the 2011 ParisFog Campaign 总被引：1，自引：1，他引：0
Laurent Menut Sylvain Mailler Jean-Charles Dupont Martial Haeffelin Thierry Elias 《Boundary-Layer Meteorology》2014,150(2):277-297
Radiative fog formation is a complex phenomenon involving local physical and microphysical processes that take place when particular meteorological conditions occur. This study aims at quantifying the ability of a regional numerical weather model to analyze and forecast the conditions favourable to radiative fog formation at an instrumental site in the Paris area. Data from the ParisFog campaign have been used in order to quantify the meteorological conditions favorable to radiative fog formation (pre-fog conditions) by setting threshold values on the key meteorological variables driving this process: 2-m temperature tendency, 10-m wind speed, 2-m relative humidity and net infrared flux. Data from the ParisFog observation periods of November 2011 indicate that use of these thresholds leads to the detection of 87 % of cases in which radiative fog formation was observed. In order to evaluate the ability of a regional weather model to reproduce adequately these conditions, the same thresholds are applied to meteorological model fields in both analysis and forecast mode. It is shown that, with this simple methodology, the model detects 74 % of the meteorological conditions finally leading to observed radiative fog, and 48 % 2 days in advance. Finally, sensitivity tests are conducted in order to evaluate the impact of using larger time or space windows on the forecasting skills. 相似文献
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Jean-Charles Dupont Martial Haeffelin Alain Protat Dominique Bouniol Neda Boyouk Yohann Morille 《Boundary-Layer Meteorology》2012,143(1):207-225
A suite of active and passive remote sensing instruments and in-situ sensors deployed at the SIRTA Observatory (Instrumented
Site for Atmospheric Remote Sensing Research), near Paris, France, for a period of six months (October 2006–March 2007) document
simultaneously radiative, microphysical and dynamic processes driving the continental-fog life cycle. The study focuses on
a 6-day period between 23 and 29 December 2006 characterized by several stratus-cloud lowering and lifting events and almost
18 h of visibility below 1 km. Conceptual models and different possible scenarios are presented here to explain the formation,
the development and the dissipation phases of three major stratus–fog events and to quantify the impact of each driving process.
For example, slowly evolving large-scale conditions characterized by a slow continuous cloud-base lowering, followed by a
rapid transient period conductive to fog formation and dissipation, are observed for cases 1 and 3. During this stable period,
continuous cloud-top radiative cooling (≈ −160 Wm−2) induces a progressive and slow lowering of the cloud base: larger droplets at cloud top (cloud reflectivity approximately
equals to −20 dBZ) induce slow droplet fall to and beyond cloud base (Doppler velocity ≈ −0.1 ms−1), cooling the sub-cloud layer by evaporation and lowering the saturation level to 100 m (case 1) or to the surface (cases
2 and 3). Suddenly, a significant increase in Doppler velocity magnitude ≈ −0.6 ms−1 and of turbulent kinetic energy dissipation rate around 10−3 m2s−3 occurs at cloud base (case 1). These larger cloud droplets reach the surface leading to fog formation over 1.5 h. The Doppler
velocity continues to increase over the entire cloud depth with a maximum value of around −1 ms−1 due to the collection of fog droplets by the drizzle drops with high collection efficiency. As particles become larger, they
fall to the ground and lead to fog dissipation. Hence, falling particles play a major role in both the formation and also
in the dissipation of the fog. These roles co-exist and the balance is driven by the characteristics of the falling particles,
such as the concentration of drizzle drops, the size distribution of drizzle drops compared to fog droplets, Doppler velocity
and thermodynamic state close to the surface. 相似文献
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Gunnar Luderer Enrica DeCian Jean-Charles Hourcade Marian Leimbach Henri Waisman Ottmar Edenhofer 《Climatic change》2012,114(1):59-78
This paper analyzes the regional distribution of climate change mitigation costs in a global cap-and-trade regime. Four stylized burden-sharing rules are considered, ranging from GDP-based permit allocations to schemes that foresee a long-term convergence of per-capita emission permits. The comparison of results from three structurally different hybrid, integrated energy-economy models allows us to derive robust insights as well as identify sources of uncertainty with respect to the regional distribution of the costs of climate change mitigation. We find that regional costs of climate change mitigation may deviate substantially from the global mean. For all models, the mitigation cost average of the four scenarios is higher for China than for the other macro-regions considered. Furthermore, China suffers above-world-average mitigation costs for most burden-sharing rules in the long-term. A decomposition of mitigation costs into (a) primary (domestic) abatement costs and (b) permit trade effects, reveals that the large uncertainty about the future development of carbon prices results in substantial uncertainties about the financial transfers associated with carbon trade for a given allocation scheme. This variation also implies large uncertainty about the regional distribution of climate policy costs. 相似文献