Overview
Seasonal snowpacks in alpine regions of the world provide
much of the water used in lower elevation regions.
These alpine catchments are potentially sensitive to
changes in climate and chemical loading, particularly acid deposition.
Both of these changes will affect the quantity, quality and
timing of runoff within alpine catchments.
Climatic changes may be particularly important
in seasonally snow covered areas because
the volume and timing of runoff generated from
the snowpack depends on the exchange
of energy from the atmosphere to the snow surface.
The prevalence of thin, sparse soil derived from
granitic rocks reduces the capacity of many
alpine catchments to neutralize acid precipitation,
and physicochemical processes
in the snowpack result in flushing of ionic
solutes from the pack at the onset of snow melt.
We are using numerical models to assess the
combined effects of climatic perturbations and
chemical loading on alpine catchments. Results address
issues in both water resources and environmental
quality.
Ionic pulse observed in a 1 x 1 meter square lysimeter
at our Mammoth Mountain, California study site, 1989 (Bales et al., Hydrol.
Proc. 7:389, 1993.)
Modeled and observed ionic pulse for Emerald Lake watershed, California, 1986
(Wolford, submitted.)