Datensatz

Zusammenfassung

The debris cover anomaly refers to the tendency of debris-covered glaciers to show similar ablation rates as of clean ice glaciers at the same elevation despite the insulating effect of debris. Mainly, the supraglacial ice cliffs and water bodies contribute to this comparable phenomenon. Ice cliffs contribute significantly to the mass loss and resultant runoff from the glaciers. Very little is known about the ice cliff ablation rates in the Himalayan region in very short time-scales. . In this study, we scanned an ice cliff (~ 10m x 3m x 13m) on Machoi Glacier during a three-day field visit to Machoi Glacier (34.290N, 75.527E) using a FARO 350S+ Lidar scanner. We scanned the ice cliff multiple times to capture changes on hourly and daily scales. The scanner obtained a very precise and high-resolution point cloud of the ice cliff. We subsequently applied the M3C2 approach to determine the difference between the two point clouds obtained at two different time epochs. We find that the ice cliff melt varies between 0.17cm/hr and 1.97cm/hr peaking at 15.00 hours (local time, IST). On a daily scale, the ice cliff melted at a rate of 11 cm/day (0.46 cm/hr), which is tenfold more than other debris-covered areas of Machoi Glacier at the same altitude, highlighting the insulating effect. In the scenario of regional and global warming these ice cliffs tend to increase in size (or exposure) and numbers. Our results highlights that they significantly contribute to local glacier melting in very short time intervals.