Seasonal enrichment of heavy isotopes in meltwater runoff from Haig Glacier, Canadian Rocky Mountains

Glacier melt provides an important source of freshwater, particularly during dry years and late in the summer, after most seasonal snow has melted. Glaciers are losing mass world’s mountain regions, which leads to uncertainties around availability freshwater downstream catchments. While contributions glacial meltwater rivers can be quantified through hydrograph separation methods, changes chemical characteristics may impact these calculations. We collected samples supraglacial ice proglacial stream water over course a season at Haig Canadian Rocky Mountains analyzed for stable isotopes (oxygen-18 deuterium) dissolved major ions assess their variability. identify isotopic enrichment on surface as turns wet eventually bare that remains. This is reflected ratios stream. Two possible explanations include: 1) sublimation or liquid evaporation glacier surface, 2) fractionation diurnal freeze-thaw cycles, with heavier preferentially refreezing. evaluate both scenarios conclude processes likely active, effects sufficient explain much observed runoff.