Estimating Long-Term Solar Irradiance Variability: A New Approach     

Vigouroux  Anne  Pap  Judit M.  Delache  Philippe 《Solar physics》1997,176(1):1-21

The detection of solar irradiance variations (both bolometric and at various wavelengths) by satellite-based experiments during the last one-and-a-half decades stimulated modeling efforts to help identify their causes and to provide estimates of irradiance data for those time intervals when no satellite observations exist. In this paper we present estimates of the long-term irradiance changes developed with Fourier and wavelet transforms. The month-to-month irradiance variations, after removing the solar cycle related long-term changes, are studied with the cross-correlation technique. Results of the analysis reveal a significant phase shift at 3 months between the full-disk magnetic field strength and total solar and UV irradiance, with irradiance leading the magnetic field variability. In addition to this time delay between the changes in solar irradiance and the magnetic field, a 10-month phase shift has been found between the UV flux at 280 nm and total solar irradiance corrected for sunspot darkening. The existence of these phase shifts suggests the possibility of a coupling between the physical processes taking place below, in, and above the photosphere.  相似文献   

Nearby Protoclusters as Laboratories for Understanding Star Formation on Galactic Scales     

Philippe André 《Astrophysics and Space Science》2002,281(1-2):51-66

Detailed studies of nearby cluster-forming molecular clouds can help us understand the physical processes by which most stars form in galaxies. I review recent advances made on this subject. Submillimeter observations of nearby protoclusters suggest that stars are generally built from finite, detached reservoirs of mass inside molecular cloud cores, and point to a cloud fragmentation origin for the IMF. Much progress in this field will come from future large submillimeter instruments such as Herschel and ALMA. This revised version was published online in September 2006 with corrections to the Cover Date.  相似文献   

Prediction-Focused Subsurface Modeling: Investigating the Need for Accuracy in Flow-Based Inverse Modeling   总被引：1，自引：1，他引：0  

Céline Scheidt  Philippe Renard  Jef Caers 《Mathematical Geosciences》2015,47(2):173-191

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Laura Sigg: Investigating the Speciation,Bioavailability and Ecotoxicology of Trace Metals in Natural Waters     

Bernhard Wehrli  Philippe Behra 《Aquatic Geochemistry》2015,21(2-4):59-64

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Benchmarks for multicomponent reactive transport across a cement/clay interface     

Nicolas C. M. Marty  Olivier Bildstein  Philippe Blanc  Francis Claret  Benoit Cochepin  Eric C. Gaucher  Diederik Jacques  Jean-Eric Lartigue  Sanheng Liu  K. Ulrich Mayer  Johannes C. L. Meeussen  Isabelle Munier  Ingmar Pointeau  Danyang Su  Carl I. Steefel 《Computational Geosciences》2015,19(3):635-653

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Highly gravity-driven flow of a NAPL in water-saturated porous media using the discontinuous Galerkin finite-element method with a generalised Godunov scheme     

Lauriane Schneider  Raphaël di Chiara Roupert  Gerhard Schäfer  Philippe Helluy 《Computational Geosciences》2015,19(4):855-876

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Can shallow open-loop hydrothermal well-doublets help remediate seawater intrusion?     

François De Keuleneer  Philippe Renard 《Hydrogeology Journal》2015,23(4):619-629

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Climate variability and trends in downscaled high-resolution simulations and projections over Metropolitan France   总被引：2，自引：1，他引：1  

Robert Vautard  Thomas Noël  Laurent Li  Mathieu Vrac  Eric Martin  Philippe Dandin  Julien Cattiaux  Sylvie Joussaume 《Climate Dynamics》2013,41(5-6):1419-1437

In order to fulfill the society demand for climate information at the spatial scale allowing impact studies, long-term high-resolution climate simulations are produced, over an area covering metropolitan France. One of the major goals of this article is to investigate whether such simulations appropriately simulate the spatial and temporal variability of the current climate, using two simulation chains. These start from the global IPSL-CM4 climate model, using two regional models (LMDz and MM5) at moderate resolution (15–20 km), followed with a statistical downscaling method in order to reach a target resolution of 8 km. The statistical downscaling technique includes a non-parametric method that corrects the distribution by using high-resolution analyses over France. First the uncorrected simulations are evaluated against a set of high-resolution analyses, with a focus on temperature and precipitation. Uncorrected downscaled temperatures suffer from a cold bias that is present in the global model as well. Precipitations biases have a season- and model-dependent behavior. Dynamical models overestimate rainfall but with different patterns and amplitude, but both have underestimations in the South-Eastern area (Cevennes mountains) in winter. A variance decomposition shows that uncorrected simulations fairly well capture observed variances from inter-annual to high-frequency intra-seasonal time scales. After correction, distributions match with analyses by construction, but it is shown that spatial coherence, persistence properties of warm, cold and dry episodes also match to a certain extent. Another aim of the article is to describe the changes for future climate obtained using these simulations under Scenario A1B. Results are presented on the changes between current and mid-term future (2021–2050) averages and variability over France. Interestingly, even though the same global climate model is used at the boundaries, regional climate change responses from the two models significantly differ.  相似文献   

A note on climate change adaptation for seaports: a challenge for global ports, a challenge for global society     

Austin H. Becker  Michele Acciaro  Regina Asariotis  Edgard Cabrera  Laurent Cretegny  Philippe Crist  Miguel Esteban  Andrew Mather  Steve Messner  Susumu Naruse  Adolf K. Y. Ng  Stefan Rahmstorf  Michael Savonis  Dong-Wook Song  Vladimir Stenek  Adonis F. Velegrakis 《Climatic change》2013,120(4):683-695

With 80 % of world trade carried by sea, seaports provide crucial linkages in global supply-chains and are essential for the ability of all countries to access global markets. Seaports are likely to be affected directly and indirectly by climatic changes, with broader implications for international trade and development. Due to their coastal location, seaports are particularly vulnerable to extreme weather events associated with increasing sea levels and tropical storm activity, as illustrated by hurricane “Sandy”. In view of their strategic role as part of the globalized trading system, adapting ports in different parts of the world to the impacts of climate change is of considerable importance. Reflecting the views of a diverse group of stakeholders with expertise in climate science, engineering, economics, policy, and port management, this essay highlights the climate change challenge for ports and suggests a way forward through the adoption of some initial measures. These include both “soft” and “hard” adaptations that may be spearheaded by individual port entities, but will require collaboration and support from a broad range of public and private sector stakeholders and from society at large. In particular, the essay highlights a need to shift to more holistic planning, investment and operation.  相似文献   

NanoSIMS analysis of organic carbon from the Tissint Martian meteorite: Evidence for the past existence of subsurface organic‐bearing fluids on Mars     

Yangting Lin  Ahmed El Goresy  Sen Hu  Jianchao Zhang  Philippe Gillet  Yuchen Xu  Jialong Hao  Masaaki Miyahara  Ziyuan Ouyang  Eiji Ohtani  Lin Xu  Wei Yang  Lu Feng  Xuchao Zhao  Jing Yang  Shin Ozawa 《Meteoritics & planetary science》2014,49(12):2201-2218

Two petrographic settings of carbonaceous components, mainly filling open fractures and occasionally enclosed in shock‐melt veins, were found in the recently fallen Tissint Martian meteorite. The presence in shock‐melt veins and the deuterium enrichments (δD up to +1183‰) of these components clearly indicate a pristine Martian origin. The carbonaceous components are kerogen‐like, based on micro‐Raman spectra and multielemental ratios, and were probably deposited from fluids in shock‐induced fractures in the parent rock of Tissint. After precipitation of the organic matter, the rock experienced another severe shock event, producing the melt veins that encapsulated a part of the organic matter. The C isotopic compositions of the organic matter (δ¹³C = ?12.8 to ?33.1‰) are significantly lighter than Martian atmospheric CO₂ and carbonate, providing a tantalizing hint for a possible biotic process. Alternatively, the organic matter could be derived from carbonaceous chondrites, as insoluble organic matter from the latter has similar chemical and isotopic compositions. The presence of organic‐rich fluids that infiltrated rocks near the surface of Mars has significant implications for the study of Martian paleoenvironment and perhaps to search for possible ancient biological activities on Mars.  相似文献