FIGURE 2. Daily values of mean temperature (red line), precipitation (grey bars?) and snow depth (blue line) measured at the in Izas catchment automatic meteorological station during the period April 1st to July 1st (2017 to 2020). Dots shows of the snow covered area (SCA in % of the area covered by the camera) obtained from time lapse photography.
Despite the occurrence of many rainy days in late May and June, a significant snow cover lasted until mid-June and snow remnants lasted until early July. In spring 2019, snow was also relatively abundant compared to 2017 and 2020. The intense snow melting recorded in April, caused the snow depletion and 40% of the catchment was free of snow by early May when new snowfalls covered again the whole catchment, exceeding 2 m of snow in some locations. May was dominated by intense melt, interrupted by new snowfall events at the end of the month. June started with a 50% of the catchment covered by snow which mostly disappeared in the next two weeks. In spring 2020 a relatively regular and continuous but not very intense melt was observed in April. At the beginning of May 80% of the catchment was covered by snow, but with a shallower snowpack than the two precedent seasons. May and the first days of June where particularly warm, driving a fast melt. Melting was interrupted by an ephemeral snowfall event in mid-May.