HW18 Advances in Remote Observation of Snow

IAHS (Hydrology)

24-Jun-2015, 16:30 - 18:00

Abstract content:

Evaluating the above-ground cosmic-ray neutron sensor for measuring snow water equivalent at a multi-sensor snow research site (Kaunertal, Austrian Alps)

To improve both process understanding and modelling of the spatial and temporal dynamics of snow accumulation and melt, the snow research site Weisssee in the Kaunertal (2480 m a.s.l., Tyrol) was upgraded in 2014. Additionally, a Hydroinnova CRS-1000 above-ground cosmic-ray neutron sensor, whose potential for soil moisture monitoring was shown recently, was installed to evaluate its capability for measuring snow water equivalent (SWE).

Since the cosmic-ray sensor is mounted above ground, it covers an area of around 600 m in diameter and potentially closes the gap between point scale measurements, hydrological models and remote sensing. However, while it is generally known in the literature that neutrons counted by the sensor are moderated not only by water in soil or organic matter but also by frozen or liquid water in the snow pack, there is only limited knowledge of its actual use for SWE monitoring.

The standard configuration of the Weisssee site consists of a fully equipped meteorological station (including all sensors for measuring the surface energy fluxes), two ultra-sonic snow depth sensors and a Snow-Pack-Analyser for measuring snow density, liquid water content and snow temperature at different levels in the snow pack. In addition, terrestrial LiDAR measurements are conducted at a monthly basis to provide snow depth patterns in the cosmic-ray sensor footprint. Mass and energy balance are simulated applying the snow-hydrological model SES at the point and hillslope scale.

This contribution highlights both potential and limitations of cosmic-ray based snow pack monitoring in alpine environments. Future research will include the use of cosmic-ray derived mean SWE values for assimilation, calibration and validation of snow pack models or remote sensing products.

P. Schattan1,2, G. Baroni2,4, K. Förster1, T. Francke3, C. Kormann3, M. Huttenlau1, S.E. Oswald3, R. Sailer4, J. Schöber5, S. Sprenger1,2, U. Strasser1,2.
1alpS Centre for Climate Change Adaptation, Area Water, Innsbruck, Austria.
2Helmholtz Centre for Environmental Research - UFZ, Computational Hydrosystems, Leipzig, Germany.
3University of Potsdam, Institute of Earth and Environmental Science, Potsdam, Germany.
4University of Innsbruck, Institute of Geography, Innsbruck, Austria.
5TIWAG, Hydropower Planning Department, Innsbruck, Austria.


Above-Ground Cosmic-Ray Sensor     Terrestrial LiDAR     Multi-Sensor Snow Research Site