Bourgeat S.,Institute Of Geographie Alpine
Annales de Geographie | Year: 2010
From 1960 to 1984, geographic scientific journals reviewed a great number of theses. Such writings even constituted the main written discourse about the thesis. In addition to their functional aspect, that is to give summaries of long and sometimes inaccessible works, they represented a typical genre of scientific writing. They were a real framework for a discourse on the thesis, corresponding to what the scientific community was expecting in terms of either substance or form. This discourses thus played a regulatory role. Secondarily, French geography underwent a paradigm shift from 1960 to 1984. How did these reviews support this change ? © Armand Colin.
Dumas M.D.,Joseph Fourier University |
Dumas M.D.,Institute Of Geographie Alpine
Theoretical and Applied Climatology | Year: 2013
In mountain environments, local factors such as topography or exposure to the sun influence the spatial distribution of temperatures. It is therefore difficult to characterise the global evolution of temperatures over several decades. Such local effects can either accentuate or attenuate thermal contrasts between neighbouring areas. The present study uses two regional thermal indicators-thermal gradients and temperatures reduced to sea level-to monitor the monthly evolution of minimum and maximum temperatures in the French Northern Alps. Measures were calculated for the period extending from 1960 to 2007 based on data from 92 measuring stations. Temperature gradients were computed and further used to monitor the altitudinal evolution of temperatures. A characteristic regional temperature was determined for the whole of the French Northern Alps based on temperatures reduced to sea level, and changes in temperatures since 1960 were assessed. Multiple linear regression models made it possible to extend measurements over a longer period and to make enhanced calculations of temperature changes in the mountains since 1885. This is the first study to examine temperature changes in the French Northern Alps over such an extended period. Gradient data suggest that over the last 50 years, temperatures have changed at all altitudes. In addition, the evaluation of the temperature rise over 100 years reveals that minimal and maximal monthly temperatures trends are only significant a few months of the year. © 2012 Springer-Verlag.
Nadai A.,Center International Of Recherche Sur Lenvironnement Et Developpement Cired |
Labussiere O.,Institute Of Geographie Alpine |
Debourdeau A.,Ariane Debourdeau AgroParistech |
Regnier Y.,CLER |
And 2 more authors.
Energy Policy | Year: 2015
This paper is interested in sustainable energy initiatives in French rural areas. It follows up the UK debate about 'localism'. UK policy localism has been cast as neoliberal, framing communities as competent and competitive actors, morally responsible and accountable for their destiny.In France, the emerging policy localism is surfing on an ongoing political structuration of innovative rural territories - 'Positive Energie Territories' (TEPOS). The paper presents and discusses the results of a rough census (undertaken in 2012) of significant experiences in this domain. It points to a few experiences and depicts them as risky, trial-and-error transcalar processes that endow locally emergent energy issues with a political dimension. To this extent, they amount to a different way of doing energy policy.The analysis points to an ambiguity in French policy localism. This localism may pave the way for an upscaling of the ongoing TEPOS political structuration, or tend to make TEPOS into demonstration territories within a neoliberal RTD policy approach. In the latter case, it may not necessarily fit territories to pursue their political structuration with a view to the energy transition. © 2014 Elsevier Ltd.
The internal structure of rock glaciers and recently deglaciated slopes as revealed by geoelectrical tomography: insights on permafrost and recent glacial evolution in the Central and Western Alps (Italy-France)
Ribolini A.,University of Pisa |
Guglielmin M.,University of Insubria |
Fabre D.,French National Conservatory of Arts and Crafts |
Bodin X.,University of Waterloo |
And 4 more authors.
Quaternary Science Reviews | Year: 2010
Ground ice of permafrost origin and sedimentary ice of glacial origin can coexist in locations where rock glaciers and glaciers interacted, as well as in glacigenic sediments abandoned by a retreating glacier and subsequently exposed again to atmospheric cooling. Some of these geomorphological settings in the Central (Foscagno rock glacier) and Western Alps (Marinet and Schiantala rock glaciers, Schiantala debris-covered glacier, Maledia glacier) were explored by means of geoelectrical tomographies. The aim was that of inferring the presence of ice and cryologically interpreting electrical stratigraphies in order to test whether or not the internal structure of these landforms can be used for the reconstruction of recent permafrost and glacier evolution. Geomorphological data assisted these reconstructions and available borehole stratigraphies were used to calibrate the resistivities. Along with the ice-debris mixture, massive ice has also been found as lenses both at the apex and the front of the studied rock glaciers. These lenses of sedimentary origin are thought to be transferred from a glacier snout to sectors of rock glacier and eventually embedded into the permafrost creep. The scarcity of frozen debris in the mid-upper part of the rock glaciers - as revealed by low resistivity values - can be due to the disruptive effect of the over-riding glacier over the permafrost. The near-surface sedimentary ice masses detected along the slopes of the studied glacial cirques are interpreted as or debris-covered terminations of the glaciers still visible upward, or as fragments of it detached by the main bodies. These ice masses are locally associated to medium-high resistive sediments, consistent with permafrost occurrence. This indicates that the non-glacial environment established during the deglaciation allowed the onset of frozen sediments formation. Overall, the results indicate that internal structure of rock glaciers and recent-deglaciated slopes can store the different climate-related episodes occurred in a specific area, such as those linked to the shifting between glacial to criotic condition and vice-versa. © 2009 Elsevier Ltd. All rights reserved.
The consequences of changes in forest land cover in the alpine and Jurassic massifs on the physico-chemical status of deep lake waters [L'évolution forestiére dans les massifs alpins et Jurassiens: Conséquence directe sur l'état physico-chimique des niveaux profonds des lacs?]
Nghiem V.T.,Institute Of Geographie Alpine |
Nedjai R.,Institute Of Geographie Alpine |
Messaoud N.N.,Blida University
Revue de Geographie Alpine | Year: 2011
The issue of acidification in lake waters has been the topic of numerous scientific studies in northern Europe and North America. In recent years, interest in the topic has spread to southern Europe and Asia because similar symptoms have been observed (drop in pH and in redox potential, generally accompanied by oxygen depletion). All the scientific work on the issue has concluded that the phenomenon is general and affects, to different degrees, lakes located at low to medium altitudes in mountains (the Vosges mountains and more recently the Jura mountains, in France). The difference in degree is often interpreted as the result of different combinations from three sources, namely acid rain, direct discharges of pollutants and the spread of forests (essentially conifer species). The first two sources have been confirmed, but the third is less perceptible due to slow progression of the phenomenon. Analysis and modelling of changes in land cover in the Hérisson river basin in the Jura mountains (largely carbonated soils) confirmed the direct impact of the forest cover on the physico-chemical quality of lake waters, in particular at the deeper levels (hypolimnion) over the past 30 years. The impact is reinforced by the considerable presence of peat zones around the lakes which, during high-water periods, contribute large quantities of dissolved, particulate organic matter. The goal of this work is to show the direct impact of the increasing forest cover observed on the Jurassic plateaus, caused by a considerable reduction in farming activity over the past 30 years. This work focuses on an analysis of land cover (vegetation), using four satellite images spanning the period from 1975 to 2006, and calls on hydrogeochemical modeling (WARMF) to evaluate changes in the physico-chemical quality, i.e. acidification, of deep lake waters. This first step is followed by a predictive phase prior to measuring the intensity of the physico-chemical changes (pH and redox) over the next 20 years to 2030. The existence of thisphenomenon confirms the massive releases of heavy metals recently noted and the biological weakening observed in certain lakes, notably among the benthic fauna. © Journal of Alpine Research.