A Scaling Relation for Cryoconite Holes

Abstract

AbstractTiny cryoconite holes are commonly found on glacier surfaces. Despite a long history of research on them, their influence on glacier‐scale mass balance and runoff are not well understood. We model the absorption of solar radiation at the bottom of cylindrical cryoconite holes, incorporating the three‐dimensional geometry. The simulated holes achieve a limiting steady‐state depth, where the daily melt rate at the bottom of the holes matches that at the glacier surface. This implies a feedback loop restricting the excess ice melt due to the presence of dark supraglacial impurities. The modeled steady‐state depth scales approximately linearly with the radius, consistent with in situ observations at several glaciers across the world. Given the areal coverage and radius distribution of cryoconite holes on a glacier, this scaling yields first‐order estimates of their melt contribution.