Influence of seasonality on glacier mass balance, and implications for palaeoclimate reconstructions

摘要: Climates inferred from former glacier geometries in some areas exhibit discrepancies with regional palaeoclimates predicted by General Circulation Models (GCMs) and modelling of palaeoecological data, possibly as a consequence their differing treatments climatic seasonality. Since glacier-based climate reconstructions potentially offer an important tool the calibration GCMs, which themselves need validation if used to predict future scenarios, we attempt resolve mismatches between these techniques (1) investigating influence seasonality on mass balance, (2) refining methodology for derivation palaeoclimates. Focussing Younger Dryas stadial glaciation Scotland, northeast Atlantic, show that sea-ice amplified led significantly drier than has been suggested interpretations. This was characterised relatively short ablation season survival more substantial winter snowpack. We suggest palaeoglaciological studies were account changes seasonal temperature precipitation variability, results would agree closely cold, arid, Atlantic palaeoenvironment atmospheric northwest European pollen studies, therefore provide accurate constraints GCM calibration.