Abstract
Abstract. Snow is a major contributor to stream flow in alpine watersheds and quantifying snow depth and distribution is important for hydrological research. However, direct measurement of snow in rugged alpine terrain is often impossible due to avalanche and rock fall hazard. A laser rangefinder was used to determine the depth of snow in inaccessible areas. Laser rangefinders use ground based light detection and ranging technology but are more cost effective than airborne surveys or terrestrial laser scanning systems and are highly portable. Data were collected within the Opabin watershed in the Canadian Rockies. Surveys were conducted on one accessible slope for validation purposes and two inaccessible talus slopes. Laser distance data was used to generate surface models of slopes when snow covered and snow-free and snow depth distribution was quantified by differencing the two surfaces. The results were compared with manually probed snow depths on the accessible slope. The accuracy of the laser rangefinder method as compared to probed depths was 0.21 m or 12% of average snow depth. Results from the two inaccessible talus slopes showed regions near the top of the slopes with 6–9 m of snow accumulation. These deep snow accumulation zones result from re-distribution of snow by avalanches and are hydrologically significant as they persist until late summer.
Highlights
Snow is a major component of the annual water balance in alpine watersheds (Kattelmann and Elder, 1991), and snow depth and distribution measurements are important to hydrological research (Flerchinger et al, 1992)
Snow depth was measured at four points within a square metre to minimize the influence of local topographic variability and these values were subsequently averaged to obtain the snow depth at that point
Snow depths from the two measurement methods were compared at the validation slope to determine the accuracy of the laser method
Summary
Snow is a major component of the annual water balance in alpine watersheds (Kattelmann and Elder, 1991), and snow depth and distribution measurements are important to hydrological research (Flerchinger et al, 1992). Hydrological process studies in alpine headwaters are important for understanding what changes may occur within a changed climatic regime (Zierl and Bugmann, 2005). Accurate quantification of the hydrological inputs (rain, snowmelt, glacier melt) and snowpack parameters in alpine watersheds are needed for processbased studies to understand hydrologic responses of alpine watersheds to the inputs. Quantifying snow depth and distribution is important for validation of snowmelt energy balance models (Cline et al, 1998) and snow distribution models (Liston and Elder, 2006), as well as for applications in avalanche research (Prokop, 2008)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have