Item: Ventilation and radon dynamics in maine seasonal snowcover
Title: Ventilation and radon dynamics in maine seasonal snowcover
Proceedings: Proceedings of the 2004 International Snow Science Workshop, Jackson Hole, Wyoming
Authors: Daniel J. Breton, Department of Physics and Astronomy, University of Maine, Orono, Maine
Abstract: Radon concentrations and fluxes were measured for seasonal snowpack on Baldpate Mtn. in Newry, Maine during the winter of 2004. A solar radiation and temperature logging system was developed to monitor the snowpack during the radonv measurements. Radon ground flux measurements were performed using a RAD-7 alpha spectrometer and ranged from 0.49 to 0.64 pCi m2 s1 for two different locations. Radon concentration as a function of time was measured inside the snowpack using a Honeywell A9000 radon monitor and showed average radon concentrations ranging from 1 to 12 pCi L1, though maximum concentrations of over 80 pCi L1 were observed. Wind-driven and natural circulation air flows within the snowpack were shown to be the major factors controlling radon dynamics. Dilution rates of 1.25 pCi L1 h1 were correlated with windspeeds of 9 m s1, while radon concentration rates of 0.8 pCi L1 h1 were observed during periods of calm. Comparison of long term track-etch cup measurements with radon diffusion theory showed that radon within the snowpack rarely exists in steady state distribution due to the ventilation eects of wind and natural circulation air flows. This study shows that radon dynamics can be used to measure air flows inside the snowpack.
Keywords: ventilation, radon, wind-driven circulation, natural circulation
Digital Abstract Not Available