Laboratory Studies of Snowmelt Using Stable Isotopes
and Rare Earth Element Tracers
Susan Taylor1,2, Xiahong Feng2, and Carl Renshaw2
Given a snowpack of known isotopic composition, can we predict the isotopic composition of the
meltwater as a function of time? Conversely, does the isotopic composition of meltwater reflect the
dynamics of snowpack melting? To address these questions we are conducting laboratory experi-
ments similar to those described by Herrmann et al. (1981); they found that the isotopic composition
of the meltwater varies significantly depending upon melting conditions such as variations in heat
flux. We seek to extend these results to include additional factors affecting the isotopic distribution,
such as particle size distribution in a snow column.
Natural and laboratory-made snow of known isotopic composition is sieved into insulated columns
and melted under controlled heat flux and temperature. To track the proportion of water originating
from different layers within the column we use chemical tracers (rare earth elements) at different
depths in the snow column. The concentration of the rare earth element tracers is set such that the
freezing point depression is below 0.005ϒC. An ICP-MS is used to analyze the meltwater for the rare
earth elements. Results of the laboratory measurements on the tracers will be presented.
These laboratory data will be used to interpret isotopic compositions and tracer concentrations in
meltwater from lysimeters at Sleepers River watershed in Vermont and Central Sierra Snow Labora-
tory in California. At both sites rare earth element tracers were sprayed on the snow surface follow-
ing large snowstorms.
Herrmann A., M. Lehrer, and W. Stichler (1981) Isotope input into runoff systems from melting
snow covers, Nordic Hydrology, 12: 309318.
1
U.S. Army Cold Regions Research and Engineering Laboratory, 72 Lyme Road, Hanover, New Hampshire
03755, USA
2 Department of Earth Sciences, Dartmouth College, Hanover, New Hampshire 03755, USA
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