Abstract. The most widely used method for snow dynamic simulation relies on temperature index approach, that makes snow melt and accumulation processes depend on air temperature related parameters. A recently used approach to calibrate these parameters is to compare model results with snow coverage retrieved from satellite images. In area with complex topography and heterogeneous land cover, snow coverage may be affected by the presence of shaded area or dense forest that make pixels to be falsely classified as uncovered. These circumstances may have, in turn, an influence on calibration of model parameters.In this paper we propose a simple procedure to correct snow coverage retrieved from satellite images. We show that using raw snow coverage to calibrate snow model may lead to parameter values out of the range accepted by literature, so that the timing of snow dynamics measured at two ground stations is not correctly simulated. Moreover, when the snow model is implemented into a continuous distributed hydrological model, we show that calibration against corrected snow coverage reduces the error in the simulation of river flow in an Alpine catchment.

A study of a 70-mile chain of prolific Leduc D-3 reef pools situated on a common aquifer is presented. The primary objective of the study was the prediction of the future performance of the centrally located Westerose D-3 Pool, as influenced by other pools in the trend. A two-dimensional mathematical model of the Acheson-Homeglen Rimbey Leduc D-3 reef chain was developed. Values of resistance and capacitance, characterizing reservoir parameters, were assigned to the grid points in the reservoir simulator. These were adjusted until a satisfactory match with twenty years of performance history was obtained. The future pressure performance and water influx or efflux under many combinations of producing rates were predicted for a ten-year period. The study indicated unusual trends in pressure and water influx behaviour resulting from interference effects. Further movement of Westerose oil into the underlying aquifer was predicted with continued injection of produced solution gas. These results were instrumental in the recent termination of gas injection into the Westerose D-3 Pool. The study also predicted the withdrawal rates necessary from the Westerose D-3 Pool to maintain the oil-water interface at its current position and to control its further movement.

The snow accumulation and melt processes are well known to play an important role on the river flow regime, in particular this is enhanced for basin with complex topography where the snow dynamic is strongly affected by hillslope exposition.This paper presents a simplified numerical model for snow dynamic simulation based 5 on air temperature thresholds that rule the snow melt and accumulation processes implemented into a continuous distributed hydrological model for hydrograph simulations at basin scale. The possibility to calibrate these temperature thresholds from snow cover maps derived from NOAA satellite images is discussed. Snow covered pixels are classified 10 according to a procedure based on aspect and elevation of each pixel, that allows to identify snow covered pixels also in shadowed areas.Snow model performance is proved at local and basin scale. The former shows a good agreement between modelled snow dynamic and observed snow height data at the Antrona station in the Toce basin; the latter shows agreement between observed 15 and simulated hydrographs for the three gauge stations of Toce, Ticino and Maggia rivers.cover areas and its relative water equivalent due to the well known difficulties of moni-3980 HESSD

Abstract. This paper presents a simplified numerical model of snow dynamic implemented into a continuous distributed hydrological model for hydrograph simulations at basin scale. This snow model is based on air temperature thresholds that rule the snow melt and accumulation processes. A procedure to calibrate these temperature thresholds from NOAA satellite snow cover maps is discussed. We show that, for an accurate model calibration from satellite images, it is necessary to consider the presence of areas with complex topography such as mountain slopes. Snow model performance is tested both at local and basin scale on Alpine catchment. At local scale a good agreement between modelled snow dynamic and observed snow height data at snow gauge stations in the river Anza basin (Italy) is shown; at basin scale agreement between observed and simulated hydrographs at the discharge station of river Toce (Italy) is reported.