Mutual effects of ablation and ice temperature in a firn-free glacier: Observations from Aug 1st glacier on northeast Tibetan plateau.

Glacier stability depends on the interaction between ice temperature and ablation, processes mediated by firn cover. Although firn-covered glaciers have been extensively investigated, firn-free glacier dynamics remain less clear. This study analyzes the coupled response of ice temperature and ablation to air temperature on the firn-free Aug 1st glacier in the northeastern Tibetan plateau. Results indicate that surface ice temperature is positively correlated with air temperature; however, without firn to store meltwater, latent heat uptake and runoff-related heat loss reduce the rate of surface warming. Increased ablation also limits heat penetration, encouraging active-layer thinning under stable internal ice temperatures. By contrast, ice temperature has little effect on ablation, which is governed mainly by air temperature. These results advance knowledge of glacier thermal behavior and underscore the importance of glacier type in modeling ice temperature evolution.