Comment on egusphere-2025-5486

Abstract. Glaciers in Central Europe are projected to almost disappear by 2100. To improve projections, glacier models must be calibrated to match observations. Using the open-source Framework for assimilating Remote-sensing Observations for Surface mass balance Tuning (FROST), we infer equilibrium-line altitudes and surface mass balance parameters for all Alpine glaciers during 2000–2019 through an Ensemble Kalman Filter. The method combines an elevation-dependent surface mass balance model with ice dynamics from Instructed Glacier Model (IGM). Validation against in-situ mass balance and end-of-summer snowline data (correlations of 0.76 and 0.62) shows that FROST enables satellite-based regional estimates of glacier equilibrium conditions.