The Infierno glacier is located in Aragon (Spain), Pyrenees mountain range, southern slope, the only one in this country that still preserves white glaciers. These are the southernmost glaciers in Europe and are currently in rapid regression. The work analyzes the evolution of the glacier between 2016 and 2022 (taking as "year zero" or starting point, 2015). In addition to the observations on the glacier itself, the variables (precipitation, temperatures, snow volumes and thicknesses) that allow understanding this evolution are studied. The results offer strong regression, with thickness losses in that period of 4.6 m and retreat of its front of 14.9 m. The evolution has frequent trend changes, linked to the interannual climatic irregularity characteristic of this mountain range. The main explanatory factor is the thermal increase. The thermal anomalies with respect to the average reference values have increased, in this period, +0.55° C. The year 2022 has been particularly warm and has recorded the greatest regression of the glacier (between May and August, the thermal anomalies were between +4° C and +2° C). Regarding precipitations, they have irregular tendencies and show a decreasing trend (-9% in the same period of time).