| Summary: | COM International audience The freshwater fluxes flowing from High Arctic glaciers mainly depend on climatic indicators (T, P) but also on other parameters like the thermal state of glacier, the water routing within and below the glacier, the permafrost distribution and the hydrodynamic characteristics of the moraines and rock structures forming the catchment. Using hydrological and geochemical methods, t he objective of the presentation is to show the relationships existing between the hydrological response of a small glacier of the Brogger peninsula (Austrelovenbre glacier), th e climatic conditions and these other parameters. I n the framework o f the Hydrosensor Flows program (IPEV 304, ANR hydrosensor flows), we have studied since 2007 the Austrelovenbr e glacier basin. Downstream, this basin has two well - defined outlets that con centrate all water fluxes: one connected to the glacier and the other influenced by the groundwater discharge in the proglacial moraine. The hydrological response of the river system has been studied by continuous monitoring of climate (T, P) and hydrologi cal parameters (Q, T, E lectrical conductivity ) at hourly intervals . In addition, geochemical measurements have performed on water samples ( major chemical elements, Sr, 18 O, 2 H, 3 H, 34 S) in order to discuss the water origin, the water routing in the catchme nt and the water - rock interaction processes. The main outlet of the glacier (Goule River) shows hydrographs (Q vs time curve) with two dynamics: a daily cyclicity and several isolated flood events. The daily fluctuations are induced by air - temperature va riations. Most main flood events mainly result from rainfall events. W hen rainy events occur during warm periods or at the beginning of the freezing period, the floods may be highly amplified. The inertia of the basin has been approached using the correlat ion methods : t he Q autocorrelation data indicate the runoff has a quite high " memory effect " (32 days). This may reveal that meltwater infiltrated into ...
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