The ablation rate under a debris layer is very difficult to measure directly at debris-covered glaciers, because the surface is highly heterogeneous, and the ablation rate varies tremendously from place to place. This paper describes previous works
on the ablation process, and a test result of a proposed method to estimate the ablation rate under a debris layer is presented for the Lirung Glacier in Langtang Valley, Nepal Himalaya.
favoured the formation of a supra-glacialablation till cover on the glacier snout. The process of ablation produced ice-cored moraines. During downwastage of ice cores, the ablation moraines cover was redeposited many times. The process of redeposition
is reflected in the preferred orientation of clasts. Since the process of ablation was continuously present during the formation of end moraine ridges, it is proposed to call them ablation end moraines.
Ablation glaciaire ; Alaska ; Bilan de masse ; Climatologie ; Climatologie synoptique ; Glacier ; Glaciologie
This paper analyzes summer, 1986, daily surface energy budgets, ablation, and variations of synoptic weather types experienced on the West Gulkana Glacier. Daily summer (June-August) synoptic conditions analyzed for the period 1948-86 were
undertaken to interpret possible long-term changes in ablation. The synoptic conditions that enhance ablation have significantly increased over the period 1957 to the present.
research utilizing glacial-ice-core composition to reconstruct paleoenvironmental records. The results of glaciological and meteorological investigations are presented and discussed in this paper.
Influence of supraglacial debris on summer ablation and mass balance in the 24K Glacier, southeast Tibetan Plateau
Air temperature ; China ; Debris cover ; Glacialablation ; Glacier ; Glacier mass balance ; Impact ; Model ; Summer ; Tibet
Ablation glaciaire ; Bilan de masse ; Chine ; Couverture détritique ; Eté ; Glacier ; Impact ; Modèle ; Température de l'air ; Tibet
Many temperate glaciers in the southeast Tibetan Plateau are covered by supraglacial debris in the ablation area. To evaluate the effect of such debris on summer ablation and mass balance, the surface ablation on the 24K Glacier was measured
in the summer of 2008. Mean ablation rates varied from 10 to 52 mm/day, strongly correlated to debris thickness. Synchronous observations of air temperature allowed application of a simple degree-day model to calculate ablation rates. Maximum values of both
ablation rate and degree-day factors appeared in the middle area of the glacier where the debris layer thickness was about 1 cm. The simulated daily ablation obtained from the degree-day approach showed that the debris layers significantly affected
The studies were carried out in the summer 1998. The article contains an attempt to evaluate the influence of morainic material placed on the glacier's surface and in the adjacent layer on the ablation's degree. The experiments with ablational
duvets attested to the importance of the type of surface on which a duvet is placed. In the case of clean ice, the ablation from an ice screw is more limited than the growth of the ice knob by approximately 14-22 %. But in the case of dirty ice
the ablation from the screw equal the growth of the ice knob under the duvet. The effect of selective melting is only observable where an ablation layer exist. - (BJ)
Description et évaluation de la différence d'érosion glaciaire et interglaciaire dans les montagnes scandinaves de l'est et de l'ouest. Approche quantitative de l'ablation en prenant en compte les fjords et lacs, les bras de mer dans les îles
Air temperature ; Glacialablation ; Glacier ; Kyrgyzstan ; Meltwater ; Moraine ; Tien Shan ; Water resources
Ablation glaciaire ; Eau de fonte ; Glacier ; Kirghizistan ; Moraine ; Ressource en eau ; Température de l'air ; Tien Chan
This paper presents results from southern Inylchek Glacier in the highly continental central Tian Shan, where sub-debris ablation was measured with stakes and simulated using air temperature and water vapour pressure. Parallel observations of air
temperature allowed the application of a simple degree-day approach and the calculation of ablation rates. It is proved that air temperature is already a very good melt indicator.
Ablation glaciaire ; Canada ; Eau de fonte ; Eau souterraine ; Ecoulement fluvial ; Glace du sol ; Northwest Territories ; Pergélisol ; Ruissellement ; Variation saisonnière ; Zone froide
Etude de la variation temporelle et des effets de l'ablation des lentilles de glace superficielle sur l'écoulement fluviatile avec une analyse de l'équilibre hydrique et des isotopes dans un affluent de Manners Creek, des Territoires du Nord-Ouest
. Le rôle hydrologique de l'ablation des lentilles de glace superficielle est déterminé par l'interaction entre l'épisode de fonte, la magnitude du réapprovisionnement en eau de la nappe souterraine, l'étendue spatiale du pergélisol et la profondeur du
Surface heat balance and spatially distributed ablation modelling at Koryto Glacier, Kamchatka Peninsula, Russia
Air temperature ; Asian part of Russia ; Digital elevation model ; Glacialablation ; Glacier ; Glaciology ; Heat balance ; Kamchatka ; Model ; Spatial variation
Ablation glaciaire ; Bilan thermique ; Glacier ; Glaciologie ; Kamčatka ; Modèle ; Modèle numérique de terrain ; Russie d'Asie ; Température de l'air ; Variation spatiale
of the glacier. Then, they use air temperature and global radiation data as model inputs for a new distributed ablation model based on an empirical approach that can estimate hourly changes in the spatial distribution of ablation rate. Discussion of the results
Ablation of ice-cored moraine in a humid, maritime climate : Fox Glacier, New Zealand
Air temperature ; Climate ; Debris cover ; Digital elevation model ; Glacialablation ; Glacial features ; Meltwater ; Moraine ; New Zealand ; Sandur ; South Island
Ablation glaciaire ; Climat ; Couverture détritique ; Eau de fonte ; Fox Glacier ; Glaciaire ; Modèle numérique de terrain ; Moraine ; Nouvelle-Zélande ; Sandur ; South Island ; Température de l'air
To evaluate the effects of varying debris-cover and climate on ice-melt in a maritime mid-latitude setting, an 11-day ablation stake study was undertaken on ice-cored moraine at Fox Glacier. Ablation rates varied with enhancement of melt-rate under
thin debris-covers. Air temperature from nearby Franz Josef Glacier allowed for a simple degree-day approach to ablation calculations, with regression relationships indicating air temperature is the key climatic control on melt. Digital elevation models
produced from topographic surveys of the ice-cored moraine over the following months indicated that ablation rates progressively decreased over time, probably due to melt-out of englacial debris increasing debris-cover thickness. The morphology
Des mesures d'accumulation et d'ablation ont été effectuées à partir de l'année hydrologique 1992/93 sur quelques glaciers des Alpes Lombardes. Les 2 glaciers (Scalino et Sforzellina) ont un bilan net de l'année 1992/93 très négatif. Une comparaison
possibility of obtaining numeric 3D-reconstructions on the surface form of former ice sheets, given their former margins and the physical character of the substratum. Also results obtained from insolation calculations as well as empirical knowledge on ablation