USE OF PROXIMAL GAMMA-RAY SPECTROSCOPY FOR NEAR REAL-TIME DETECTION OF SNOW WATER EQUIVALENT IN JIZERA MTS.

The snow water equivalent is an important snow characteristic as it provides hydrologically relevant information on the amount of water stored in the snowpack. The experimental catchment in the Jizera Mountains was equipped with the gamma-ray spectroscope CS725. The sensor uses emitted electromagnetic signals of isotopes 40K and 208Tl to remotely and continuously measure the snow water equivalent (SWE). Two winter seasons, 2018-2019 and 2019-2020 were monitored, and the obtained data were analyzed together with the complementary measurements available (snow depth, precipitation, air temperature). The sensor was tested in contrasting conditions of the precipitation-rich winter period 2018-2019 and the mild winter period 2019-2020. Our measurement showed that the SWE values derived from both isotopes are very similar and logically correspond well with the other measurements at the site. As far as we know, the first use of the sensor in the Czech Republic has proven usability in the conditions of the temperate montane catchment.