Satellite telemetry of surface ablation to inform spatial melt modelling and event-scale monitoring, Place Glacier, Canada

Abstract. We designed and deployed four low-cost automated smart stakes equipped with Iridium satellite telemetry to monitor Place Glacier, British Columbia, Canada during the 2024 ablation season. The smart stakes recorded air temperature, relative humidity, and distance to glacier surface every 15 min from 8 May to 14 November 2024. This high-temporal resolution, near real-time melt data sampled an elevation gradient and across varied glacier surfaces. Smart stake data yielded ice melt factors of −4.21 to −4.87 mm w.e. °C−1 d−1 and snow melt factors of −3.52 to −4.08 mm w.e. °C−1 d−1 , consistent with previous studies. Shortwave radiation melt factors were -0.041±0.006 and -0.029±0.025 mm w.e. W−1 m−2 d−1 for snow and ice, respectively. We combined the melt factors with repeat airborne lidar, daily air temperature lapse rates, incoming shortwave radiation, and satellite snow cover observations in a distributed Enhanced Temperature-Index model for the 2024 ablation season. Validation against manual ablation stakes showed reasonable agreement (R2=0.63, RMSE = 0.33 m w.e.) and improved agreement against geodetic mass change (R2=0.82, RMSE = 0.23 m w.e.). The distributed melt model estimated a total seasonal melt volume of 12.1×106 m3, representing a summer mass balance of −4.33 m w.e. for the glacier. Event-scale analysis revealed that three multi-day heat events with mean daily air temperatures above 10 °C (5–22 July, 1–12 August, and 29 August–9 September) that accounted for over half of the total seasonal melt despite comprising only one-third of the ablation season. Maximum daily melt rates reached −77 mm w.e. d−1 during these heat events. On-glacier air temperature inversions up to +8.0 °C km−1 were observed on multiple occasions, highlighting the importance of distributed temperature measurements for accurate melt modelling. The low-cost smart stake system demonstrates significant potential as a transferable automated glacier monitoring system, providing near real-time data transmission.