163: Hydrochemical Processes in Snow-covered Basins

This article reviews several aspects of snow hydrochemistry: the chemistry of snowfall including chemical incorporation in snowfall and snowfall chemistry variability, the chemistry of cold, dry snowcovers including snow redistribution, snow-atmosphere chemical exchange and in-pack chemical transformations, the chemistry of wet and melting snowcovers including solute leaching, particulate interactions and microbial activity, and snow-covered basin hydrochemistry with an emphasis on nutrient chemistry. The emphasis is on the processes of chemical transformation in seasonal snowpacks and meltwaters with strong attention to the broad ecosystem view of snow chemistry rather than solely focusing on acidification efects from snowmelt. The seasonal snowcover is shown to be a dynamic hydrochemical system with strong ecological interactions. Besides wet deposition by snowfall and rain, the processes of wind redistribution, dry deposition, volatilization, crystal metamorphism, photolysis, microbial uptake and release, solute elution, and meltwater movement strongly affect the chemistry of both the snowpack and meltwaters. Snowmelt chemistry alone is rarely directly responsible for major chemical fluctuations in water bodies, but meltwater has an important role in transporting ions from soils and organic material to water bodies