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Résultats de la recherche (1930 résultats)

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  • Antarctica ; Cenozoic ; Deglaciation ; Glacial features ; Glacier mass balance ; Ice sheet ; Palaeoclimatology
  • . Furthermore, an East Antarctic outlet glacier has not expanded into east-central Wright Valley in at least the last 3.8 Ma, thus precluding ice-sheet overriding of the Dry Valleys region during this interval. Overall, Wright Valley data imply that the adjacent
  • East Antarctic Ice Sheet has been stable for at least the last 3.8 Ma.
  • Application of kriging interpolation for glacier mass balance computations
  • Special issue : Methods of mass balance measurements and modeling
  • Glacier ; Glacier mass balance ; Glaciology ; Krigeage ; Random process ; Spatial distribution ; Sweden
  • Bilan de masse ; Distribution spatiale ; Glacier ; Glaciologie ; Krigeage ; Processus aléatoire ; Suède
  • This paper investigates the sensitivity of interpolation results to the choice of various kriging parameters when applying kriging interpolation for mass balance computations. In this study kriging was applied to mass balance data of Storglaciären
  • Atmospheric circulation and variations in Scandinavian glacier mass balance
  • Atmospheric circulation ; Atmospheric dynamics ; Climate oscillation ; Europe ; Glacier ; Glacier advance ; Glacier fluctuation ; Glacier mass balance ; North Atlantic Ocean ; Ocean atmosphere interaction ; Scandinavia ; Seasonal variation
  • Atlantique Nord ; Avancée du glacier ; Bilan de masse ; Circulation atmosphérique ; Dynamique de l'atmosphère ; Europe ; Fluctuation du glacier ; Glacier ; Interaction océan-atmosphère ; Oscillation climatique ; Scandinavie ; Variation saisonnière
  • Mountain glaciers in Scandinavia are currently advancing while most of the monitored mountain glaciers of the world are retreating. The AA. examine how the mass balance of glaciers in Scandinavia are correlated with atmospheric variability
  • Effective sample size for glacier mass balance
  • Special issue : Methods of mass balance measurements and modeling
  • Canada ; Glacier ; Glacier mass balance ; Kyrgyzstan ; Methodology ; Model ; Northwest Territories ; Principal components analysis ; Sampling ; Spatial statistics
  • Analyse en composantes principales ; Bilan de masse ; Canada ; Echantillonnage ; Glacier ; Kirghizistan ; Modèle ; Méthodologie ; Northwest Territories ; Statistique spatiale
  • The A. aims to determine the effective sample size of 2 glaciers by analysis of the spatial correlation between point mass balance measurements. Correlograms from multiple time series of point mass balance, measured on White Glacier (Axel Heiberg
  • Island, Canada) and Abramov Glacier (Alai Range, Kirgizia), show that the correlation decreases with the difference in elevation between the points. A principal component analysis confirms that the effective sample size is very small.
  • How many stakes are required to measure the mass balance of a glacier?
  • Special issue : Methods of mass balance measurements and modeling
  • Altitude ; Glacier ; Glacier mass balance ; Methodology ; Mountain ; Regression analysis ; Spatial statistics ; United States of America ; Washington State
  • Altitude ; Analyse de régression ; Bilan de masse ; Etats-Unis ; Glacier ; Montagne ; Méthodologie ; Statistique spatiale ; Washington State
  • Glacier mass balance is estimated for South Cascade Glacier and Maclure Glacier using a one-dimensional regression of mass-balance with altitude as an alternative to the traditional approach of contouring mass balance values. Two different
  • regression equations were examined. The results point to dominant effect of the gradient of mass balance with altitude of alpine glaciers compared to transverse variations. The number of mass balance measurements required appears to be scale invariant
  • for small glaciers and 5 to 10 stakes are sufficient.
  • Australia ; Chemical erosion ; Continental margin ; Erosion rate ; Escarpment ; Glacier mass balance ; Isotope analysis ; New South Wales ; Trace-element ; Weathering
  • Análisis isotópico ; Balance de masa ; Elemento-huella ; Erosión química ; Escarpadura ; Margen continental ; Meteorización ; Velocidad de erosión
  • The passive margin escarpment of south-eastern Australia has a debated but generally accepted model of propagation in which it retreated (within 40 Ma) to near its current position following rifting between Australia and New Zealand 85-100 Ma before
  • balance approach coupling major and trace element analyses with previous measurements of denudation rates using cosmogenic nuclides (10Be and 26Al). They find a slight gradient in saprolite chemical weathering rate as a percentage of total weathering rate
  • Glacier retreat, mass-balance and thinning : Sermilik Glacier, South Greenland
  • Cold area ; Glacier ; Glacier mass balance ; Glacier retreat ; Global Positioning System ; Greenland ; Ice sheet ; Model ; Remote sensing ; Satellite imagery
  • Années 1985-2000 ; Bilan de masse ; Calotte glaciaire ; GPS ; Glacier ; Groenland ; Image satellite ; Modèle ; Recul du glacier ; Télédétection ; Zone froide
  • In this paper, the retreat pattern of the Sermilik glacier tongue is documented together with observations of mass-balance conditions based on measurements carried out during the balance-years 2001/2002 and 2002/2003. Estimates of thinning along
  • the Sermilik Glacier catchment area have been derived from positive-degree-day modelling using monthly mean air temperatures at Narsarsuaq. An attempt is made to distinguish between the dynamic and mass-balance contributions, accountable for the glacier volume
  • The Tarfala mass balance programme
  • Special issue : Methods of mass balance measurements and modeling
  • Climatic warming ; Glacier ; Glacier mass balance ; Glaciology ; Measurement ; Research ; Research programme ; Sweden
  • Bilan de masse ; Glacier ; Glaciologie ; Mesure ; Programme de recherche ; Recherche ; Réchauffement climatique ; Suède
  • The purpose of the programme is to study gradients in mass balance parameters across the northern Scandinavian mountains. Storglaciären is the most important glacier in the network and is measured with high accuracy and measurement density
  • . Storglaciären is also used as a reference for all other glaciers in the programme. In general, Swedish glaciers are still responding to the major climatic warming around 1910-1920 by retreat, and the effect of very long response times. However, measured volume
  • change indicates that most glaciers are close to or varying around a quasi-steady state.
  • Recent trends in the Lemon Creek Glacier, Alaska
  • Glaciers and Late Quaternary environments of Alaska: II. Essays in honor of William O. Field
  • Alaska ; Cartography ; Geodesy ; Glacier ; Glacier fluctuation ; Glacier margin ; Glacier mass balance ; Glaciology ; Photogrammetry
  • Alaska ; Bilan de masse ; Cartographie ; Fluctuation du glacier ; Glacier ; Glaciologie ; Géodésie ; Marge glaciaire ; Photogrammétrie
  • is at a scale of 1:10,000 with a 5-m contour interval for the glacier surface. Changes between 1957 and 1989 were determined by use of the geodetic method for determining mass balance.
  • This paper reports the 1989 re-mapping of Lemon Creek Glacier, and, in conjunction with 1948 and 1957 maps of the glacier, calculation of 9-year and 32-year changes of glacier mass and terminal position. As in the earlier maps, the new map
  • Mass balance observations at Mittivakkat Glacier, Ammassalik Island, Southeast Greenland 1995-2006
  • Climate ; Climatic trend ; Glacier ; Glacier mass balance ; Greenland ; Model
  • Ammassalik ; Années 1995-2006 ; Bilan de masse ; Climat ; Glacier ; Groenland ; Groenland du Sud-Est ; Modèle ; Tendance du climat
  • Présentation et discussion des données obtenues sur les bilans de masse du glacier Mittivakkat, dans l'île d'Ammassalik, au cours des années 1995-2006.
  • A mass balance model that uses low-altitude meteorological observations and the area-altitude distribution of a glacier
  • Special issue : Methods of mass balance measurements and modeling
  • Altitude ; Glacier ; Glacier mass balance ; Glaciology ; Ground survey ; Model ; Snow line ; United States of America ; Washington State
  • Altitude ; Bilan de masse ; Etats-Unis ; Glacier ; Glaciologie ; Limite d'enneigement ; Mesure de terrain ; Modèle ; Washington State
  • A glacier mass balance model that requires only low-altitude precipitation and temperature observations and the glacier's area-altitude distribution is presented as an alternative to direct field measurements. Input to the model for South Cascade
  • are compared with balances measured at the glacier.
  • Glacier, (North Cascade Mountains, Washington State), are daily weather observations at stations 30-60 km from the glacier and at altitudes 1300 to 1500 m lower than the glacier. The independently produced simulation results for the 1959-1996 period
  • The status of research on glaciers and global glacier recession : a review
  • Bibliography ; Climatic warming ; Glacier ; Glacier mass balance ; Glacier retreat ; Global change ; Ice sheet ; Mountain ; Remote sensing ; Research technique
  • Bibliographie ; Bilan de masse ; Calotte glaciaire ; Changement global ; Glacier ; Montagne ; Recul du glacier ; Réchauffement climatique ; Technique de recherche ; Télédétection
  • This review outlines the measurements that are available, new techniques that incorporate remotely sensed data, and major findings around the world. The focus is on changes in glacier area, rather than estimates of mass balance and volume changes
  • that address the role of glacier melt in global sea-level rise. The glacier observations needed for global climate monitoring are also outlined.
  • Measurement and estimative models of glacier mass balance in China
  • Special issue : Methods of mass balance measurements and modeling
  • China ; Glacier ; Glacier mass balance ; Glaciology ; Ground survey ; Model ; Monsoon ; Mountain
  • Bilan de masse ; Chine ; Glacier ; Glaciologie ; Mesure de terrain ; Modèle ; Montagne ; Mousson
  • accumulation on those glaciers coincide with the ablation period. Therefore, the annual mass balance should be calculated neither by giving the place of annual accumulation to winter balance, nor annual ablation to summer balance. Rather, it is better done
  • Attibuted to high altitude and inland location, the glaciers in China are characterized by very low temperature. The prevailing monsoon climate delivers most of the annual precipitation over glaciated areas of China in the summer, making the major
  • by net accumulation and net ablation during the year. The monitored glaciers are few compared with the large glacierized area in China. Some estimative models are thus introduced.
  • Inferring glacier mass balance using radarsat : results from Peyto Glacier, Canada
  • Special issue : Methods of mass balance measurements and modeling
  • Alberta ; Canada ; Climatic variation ; Glacier ; Glacier mass balance ; Mountain ; Radar ; Remote sensing ; Snow cover ; Snow line
  • Alberta ; Bilan de masse ; Canada ; Glacier ; Limite d'enneigement ; Manteau nival ; Montagne ; Radar ; Télédétection ; Variation climatique
  • This paper describes efforts to use orbital synthetic aperture radar (SAR) aboard the Canadian satellite RADARSAT-1 to assess the glacier facies configuration and mass balance of Peyto Glacier for 1996. Specific recommendations are made regarding
  • the interpretation of SAR imagery over typical late-summer glaciological zones of temperate alpine glaciers and the potential application of RADARSAT SAR for mass balance studies and climate change detection in general.
  • Annual mass balance of Blue Glacier, USA : 1955-97
  • Special issue : Methods of mass balance measurements and modeling
  • Altitude ; Glacier ; Glacier fluctuation ; Glacier mass balance ; Precipitation ; Snow ; Temperature ; Topographic map ; United States of America ; Washington State
  • Altitude ; Années 1955-1997 ; Bilan de masse ; Carte topographique ; Etats-Unis ; Fluctuation du glacier ; Glacier ; Neige ; Précipitation ; Température ; Washington State
  • adjusted for seasonal variations in the snow cover. The mass balance of Blue Glacier was generally positive until the mid-1970s and negative since. The fluctuations of mass balance closely resemble those of snowfall on the glacier as estimated from
  • Mass changes of Blue Glacier, USA, are calculated from topographic maps made from vertical aerial photography in late summer of 1939, 1952, 1957, and 1987, along with laser altimetry flown in June 1996. Changes in elevation between maps were
  • Glacier mass balance : the first 50 years of international monitoring
  • Bibliography ; Climatic variation ; Europe ; Geodesy ; Glacier ; Glacier mass balance ; Global change ; Model ; North America ; Remote sensing ; Russia ; Sea level ; World
  • Amérique du Nord ; Années 1946-1995 ; Bibliographie ; Bilan de masse ; Changement global ; Europe ; Glacier ; Géodésie ; Modèle ; Monde ; Niveau marin ; Russie ; Télédétection ; Variation climatique
  • This paper reviews measurements of glacier mass balance in the period 1946-95. There are data for 246 glaciers. The available mass-balance data are biased to Western Europe, North America and the former USSR. The data are also biased towards wetter
  • conditions with too few data from the dry-cold glaciers. There is no sign of any recent global trend towards increased glacier melting, and the data mainly reflect variations within and between regions. The direct method of measuring glacier mass balance
  • Tree-ring-based mass-balance estimates for the past 300 years at Peyto Glacier, Alberta, Canada
  • Alberta ; Canada ; Dendrochronology ; Dendrology ; Eighteenth Century ; Glacier ; Glacier fluctuation ; Glacier mass balance ; Nineteenth Century ; Palaeo-environment ; Rocky Mountains ; Twentieth Century
  • Alberta ; Bilan de masse ; Canada ; Dendrochronologie ; Dendrologie ; Fluctuation du glacier ; Glacier ; Paléo-environnement ; Rocky Mountains ; Siècle 18 ; Siècle 19 ; Siècle 20
  • Tree rings were used to reconstruct mass balance for Peyto Glacier in the Canadian Rocky Mountains from A.D. 1673 to 1994. In this paper, the AA. present the firts attempt to derive a mass-balance record from independently estimated summer
  • and winter balances for a glacier. For the Canadian Rockies, they provide the only continuous record of glacier changes through the past three centuries and the latter part of the LIA for this region.
  • Map comparison or traditional mass-balance measurements : which method is better?
  • Special issue : Methods of mass balance measurements and modeling
  • Glacier ; Glacier mass balance ; Glaciology ; Map ; Measurement ; Methodology ; Norway
  • Bilan de masse ; Carte ; Glacier ; Glaciologie ; Mesure ; Méthodologie ; Norvège
  • A number of Norwegian glaciers were selected in 1960s for long-term mass-balance measurements, to produce necessary hydrological information for hydropower exploitation. Special large-scale glacier maps were produced for field work and data
  • processing. This study is concentrated on comparisons of conventional maps, and the results are compared to cumulative mass-balance data. For the maritime glacier Ålfotbreen, a cumulative mass-balance calculation gives a positive total balance, whereas
  • the map comparison indicates a total negative balance. This indicates a discrepancy between the methods, which must be accounted for.
  • Glaciological studies at Rae Glacier, Canadian Rocky Mountains
  • Canada ; Climatic variability ; Glacial ablation ; Glacier ; Glacier fluctuation ; Glacier mass balance ; Glaciology ; Mountain ; Rocky Mountains
  • Ablation glaciaire ; Bilan de masse ; Canada ; Fluctuation du glacier ; Glacier ; Glaciologie ; Montagne ; Rocky Mountains ; Variabilité climatique
  • and to characterize historical glaciological trends at the site. The glacier has a lag time of 5 to 10 years, which confirms that it is sensitive to climatic fluctuations and responds to changes in mass balance within a very short time. This observation is supported
  • The purpose of this paper is to report on glaciological investigations carried out at a single glacier in this region, the Rae Glacier. In 1990 and 1991 field research was completed to describe the physical glaciology of Rae Glacier
  • Local aspect asymmetry of mountain glaciation : a global survey of consistency of favoured directions for glacier numbers and altitudes
  • Altitude ; Glacier ; Glacier mass balance ; Inventory ; Mountain ; Spatial distribution ; World
  • Altitude ; Bilan de masse ; Distribution spatiale ; Glacier ; Inventaire ; Monde ; Montagne
  • Several factors influencing glacier mass balance vary with slope aspect. Their effects can be measured by either vector analysis of the number of glaciers with each aspect, or Fourier regression of glacier altitude, or size against aspect. Both
  • approaches are applied here to large data sets from the World Glacier Inventory, for all available regions. Favoured aspect is measured by direction of the resultant vector mean and by the direction of minimum glacier altitude for 51 regions with a total
  • of 66,084 glaciers.