Ice cover loss and debris cover evolution in the Afghanistan Hindu Kush Himalaya between 2000 and 2020

Abstract

ABSTRACT Glaciers in Afghanistan are crucial elements for water resource and summer river flows. They are also threatened by rapid climate warming. This study presents an up-to-date assessment of ice cover loss for the entire country over two periods, 2000–2008 and 2008–2020, using newly developed remote sensing indices that include a more reliable determination of changing debris cover. The results suggest an estimated ice-covered area of 2,684 ± 101 km2 in 2020, that was 75 ± 0.7% clean ice and 25 ± 3.0 percent debris-covered ice. Total ice-covered area retreated by −0.15 ± 0.01 percent yr−1 between 2000 and 2008 and −0.43 ± 0.05 percent yr−1 between 2008 and 2020. Notably, 60 percent of ice cover loss (2000–2020) related to ice cover extents with a size ≤ 2.5 km2, comprising 60 percent of the total ice-covered area in 2000. Higher altitude accumulation zones also exhibited mass loss. However, there was also substantial spatial variation in these rates of loss based on geographical region, glacier size, and climate zones. In the north-eastern regions that are geographically close to or part of the north-west Karakoram ice cover was declining at a substantially lower rate, stable, or even increasing slightly, as compared with the northern and central regions of Afghanistan.