Search results for "Global Change"
showing 10 items of 639 documents
Climate variability and change : hydrological impacts
2006
Sedimentary dynamics and extensional structuring related to early Cretaceous rifting of Neocomian and Barremian deposits of the interior basin of Gab…
2008
18 pages; International audience; Recent field and subsurface data about the early Neocomian N'dombo series and the Neocomian to mid-Barremian Schistes series of the interior basin of Gabon further our understanding of the initial stages of early Cretaceous N40–60E extensional rifting. The syn-rift series comprise fluvial–lacustrine claystones–sandstones, rare conglomerates, and carbonates. The syn-rift fill begins with braided-stream feldspathic sandstones. These are overlain first by fluvial–lacustrine deposits and then by predominantly lacustrine–palustrine claystones, which are potential petroleum source rocks. The claystones are eroded in part and are capped by the pre-Aptian angular u…
Configurations spatio-temporelles des températures et des précipitations au printemps et en été 2003 en Bourgogne : mesures Météo France et simulatio…
2010
International audience; Contexte : En Bourgogne, un collectif pluridisciplinaire piloté par Alterre travaille la question de l'adaptation au changement climatique. Une confrontation entre deux saisons végétatives (1991 et 2003) sélectionnées comme étant représentantes des conditions moyennes actuelles (1988-2007) et futures (seconde moitié du xxie siècle) est développée sur la base d'une méthodologie multi-modèles (climatique, pédologique et hydrologique).Problématique : Au-delà des éléments connus (températures élevées et pluies peu fréquentes de 2003) l'étude vise à caractériser les écarts de conditions climatiques 2003-1991 sur l'ensemble du territoire bourguignon. Les températures de la…
La Seconda Vita dell'Ambiente Costruito
2021
Il contributo inquadra i saggi, gli studi, le ricerche e progetti pubblicati sul numero 9 di AGATHÓN su ‘La Seconda Vita dell’Ambiente Costruito’, tema di interesse per il mondo accademico, delle professioni e dell’industria. Cambiamenti climatici, eccessivo consumo di suolo e di risorse non rinnovabili, produzione sempre crescente di rifiuti, emergenza pandemica e crisi socio-economica globale sono entrati di fatto nel nostro quotidiano: seppur drammatiche, per certi versi, tali questioni possono essere colte come un’opportunità per ripensare il modo e il mondo in cui viviamo. In questo contesto di ‘rivoluzione’(Floridi, 2020) e di ‘policrisi’ (Losasso, 2020), e con riferimento specifico a…
Influence of organic amendments on diuron leaching through an acidic and a calcareous vineyard soil using undisturbed lysimeters.
2008
9 pages; International audience; The influence of different organic amendments on diuron leaching was studied through undisturbed vineyard soil columns. Two composts (A and D), the second at two stages of maturity, and two soils (VR and Bj) were sampled. After 1 year, the amount of residues (diuron þ metabolites) in the leachates of the VR soil (0.19e0.71%) was lower than in the Bj soil (4.27e8.23%), which could be explained by stronger diuron adsorption on VR. An increase in the amount of diuron leached through the amended soil columns, compared to the blank, was observed for the Bj soil only. This result may be explained by the formation of mobile complexes between diuron and water-extrac…
Ensemble reconstruction constraints on the global carbon cycle sensitivity to climate
2010
The processes controlling the carbon flux and carbon storage of the atmosphere, ocean and terrestrial biosphere are temperature sensitive and are likely to provide a positive feedback leading to amplified anthropogenic warming. Owing to this feedback, at timescales ranging from interannual to the 20-100-kyr cycles of Earth's orbital variations, warming of the climate system causes a net release of CO(2) into the atmosphere; this in turn amplifies warming. But the magnitude of the climate sensitivity of the global carbon cycle (termed gamma), and thus of its positive feedback strength, is under debate, giving rise to large uncertainties in global warming projections. Here we quantify the med…
Filling the Eastern European gap in millennium-long temperature reconstructions
2013
Tree ring–based temperature reconstructions form the scientific backbone of the current global change debate. Although some European records extend into medieval times, high-resolution, long-term, regional-scale paleoclimatic evidence is missing for the eastern part of the continent. Here we compile 545 samples of living trees and historical timbers from the greater Tatra region to reconstruct interannual to centennial-long variations in Eastern European May–June temperature back to 1040 AD. Recent anthropogenic warming exceeds the range of past natural climate variability. Increased plague outbreaks and political conflicts, as well as decreased settlement activities, coincided with tempera…
Continental weathering and climatic changes inferred from clay mineralogy and paired carbon isotopes across the early to middle Toarcian in the Paris…
2014
Abstract Lower Toarcian strata (Lower Jurassic) have been extensively studied with a view to understanding the oceanographic, climatic and biological processes that drove the Earth's system into an Oceanic Anoxic Event (OAE). For this time period, the evolution of the European marine seaways is now relatively well constrained owing to multiple geochemical studies, but investigations regarding climatic trends in the continental realm remain sparse. In the present study, we test the clay mineralogy as a continental climate-sensitive proxy in the well-documented Sancerre core (southern Paris Basin). We compare variations in the kaolinite content with p CO 2 fluctuations (derived from paired ca…
Human settlement dynamics and alluvial dynamics of the Rhine River during the Holocene: Geoarchaeology of the site of Oedenburg (Haut-Rhin, France).
2007
The relationship between alluvial dynamics and control parameters such as climate are well known and understood at plurimillennial and pluriannual time-scales. But it is not really the case at multicentennial and multidecennal time-scales compatible with human society settlement time-scales. In a present and near future context, when human settlement may be affected by strong climatic variation, alluvial dynamics understanding is however a major centre of attention to the development of efficient models. To approach this scale-related question, a segment of the Upper Rhine River presenting both anastomosed and braided was investigated. This area also gives us the opportunity to study settle…
Étude de deux formations carbonifères du Morvan méridional dans le cadre de l'orogenèse hercynienne (Région du Creusot, Saône-et-Loire).
2006
18 pages; National audience; Dans la région creusotine, deux formations sédimentaires, l'une d'un âge incertain, Dévonien, Dévono-Dinantien, Dinantien, selon les auteurs, et l'autre du Stéphanien supérieur, ont été étudiées. La première nommée Formation (Fm) des Alouettes, est bordée au nord par le granite d'Uchon responsable d'un métamorphisme de contact. Des filons de microgranite la recoupent. Elle est d'abord constituée par une alternance de grès et de siltites laminées charbonneuses dans lesquelles on rencontre des rides de courant, figures d'érosion ainsi que des racines de Lépidophytes (Stigmaria) et des tiges d'Equisétales (Bornia). Cette partie est recouverte par des conglomérats à…