Meteorological forcing of unusually high glacier melt on James Ross Island, Antarctic Peninsula in summer 2022/2023: in-situ observations and WRF model simulations

Antarctic Peninsula (AP) glaciers experiencing mean summer air temperature near the melting point are highly sensitive to both long‑term climate variability and short-term but intense warm air advection events. Large scale flow during these events could be further modified by interaction with topography, e.g., by foehn development at the eastern coast of 1000 – 2000 m high AP mountain range. Foehn effect on glacier melt was extensively studied at the Larsen C Ice Shelf region. However, less attention was given to ablation events occurring at the northeastern coast, where AP mountains are less prominent, and where flow interacts also with complex topography of western Weddell Sea islands. In this contribution, we present an analysis of three pronounced melt events in summer 2022/2023 observed on the Davies Dome glacier (514 m a.s.l.) and a cirque-based Triangular Glacier (180 m a.s.l.), both located on Ulu Peninsula, northern James Ross Island. Melt events were identified and their intensity was quantified with an ultrasonic depth sensor data supplemented by snow and ice density observations. The selected events induced total snow/ice melt of ~1.19 m water equivalent (Triangular Glacier) and ~0.28 m water equivalent (Davies Dome) and significantly contributed to an anomalous ablation season 2022/2023 in this region. In-situ air temperature, wind speed, albedo, and net radiation observations allowed identification of crucial meteorological factors leading to snow and ice melt. Differences in melt regime of studied glaciers were further discussed. In addition to in-situ measurements, the Weather Research and Forecasting (WRF) model was run in a very high resolution for investigated events. The model output allowed analysis of synoptic-scale advection patterns leading to enhanced glacier ablation. An attention was given also to the effects of AP mountains and James Ross Island topography on incoming flow characteristics and possible foehn development.