Hydroclimate intensification likely aided glacier survival on Svalbard in the Early Holocene

Abstract

Accelerated Arctic warming and wetting has global impacts, as the region’s glaciers and ice caps respond to variations in temperature and precipitation, impacting global sea-level change. But as the observations needed to calibrate models are scarce, predictions cannot confirm if increases in snowfall can help offset melt. Here, we analyze two 14,000-year-long glacier-fed lake sediment records from the Svalbard archipelago to examine the response of a resilient ice cap (Åsgardfonna) to warmer-than-present Holocene Thermal Maximum conditions. End-Member Modelling allowed us to unmix the diluted grain size signal of rock flour – a widely used proxy for past glacier change, and surface runoff – an indicator of hydrological intensification. Our findings reveal that Åsgardfonna survived and may have advanced despite warmer conditions, possibly due to enhanced snowfall driven by sea-ice loss. This suggests that future increases in precipitation could moderate glacier retreat in similar settings.