Detection of frictional meltwater on snow surface using a humidity indicator

The experiments were performed at the snow lab of the Research Center Snow, Ski and Alpine Sports at the University of Innsbruck (Austria) on a linear tribometer with 18 m sliding surface length (Hasler et al., 2016). A cross-country ski (Salomon LAB WC Equipe 10 Skate, 192 cm) was moved at a sliding speed of 15 m/s. The normal load was 430 N taking into account half the weight of the skier during XC skiing. On three different days we performed experiments with different snow temperatures. First day with snow temperature -1 °C, the next day with -3 °C and then on the third day with -5 °C. The attached data files include video recordings captured with a Sony 4K camera (resolution: 1920 × 1080, frame rate: 50 fps), as well as infrared videos acquired using an IR camera (model TE-EQ1, Thermal Experts, Korea) with a resolution of 384 × 288 pixels.