AN INTEGRATED APPROACH TO MODELING HYDROLOGY AND WATER-QUALITY IN GLACIERIZED CATCHMENTS

The results are summarized of an integrated investigation of glacier g eometry, ablation patterns, water balance, meltwater routing, hydroche mistry and suspended sediment yield. The ultimate objective is to eval uate the assumptions of lumped, two-component mixing models as descrip tors of glacier hydrology, and to develop a semi-distributed physicall y based model as an alternative, The results of the study demonstrate that a reconstruction of probable subglacial drainage alignments can b e achieved through a combination of terrain modelling based on estimat ed potential surface and dye tracing experiments. Recession curve anal ysis, evidence of the seasonal instability of the englacial and subgla cial electrical conductivities assumed in a mixing model, evidence of the non-conservative behaviour of water chemistry in the presence of s uspended sediment, and evidence of the seasonal evolution of the subgl acial drainage system based on dye tracing all indicate that an altern ative to a lumped, static model of the hydrology is necessary.