NOAA/WDS Paleoclimatology - Nevado Huascarán Ice Core Dust and Snow Albedo Reconstruction 1960-2019 CE

In addition to warming and hydrological changes, glacier retreat is influenced by mineral dust and other light absorbing impurities. However, very little is known about the presence of mineral dust in the tropical Andes, making it difficult to model the radiative impact of dust on glacial surfaces. We present two sixty-year (1960-2019) ice core dust records from the col and summit of Earth’s highest tropical mountain (Nevado Huascarán, Cordillera Blanca, Peru) and use the SNICAR radiative transfer model to investigate dust-driven albedo changes over time. Our results show that, although dust concentrations have trended upward for several decades, mineral dust has only a marginal effect on the albedo of the high-altitude glaciers at Huascarán. We estimate that by the end of the century the reduction in surface albedo due to mineral dust will translate to an additional 15-70 mm w.e. of ablation on the col and 16-57 mm w.e. on the summit, or less than 5% of average net accumulation rates of today.