Greenland ice-sheet wide glacier classification based on two distinct seasonal ice velocity behaviors

• Published in: Journal of Glaciology
• Main Authors: Saurabh Vijay, Michalea D. King, Ian M. Howat, Anne M. Solgaard, Shfaqat Abbas Khan, Brice Noël
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press 2021
• Subjects: Glacier fluctuations; ice/atmosphere interactions; ice dynamics; ice velocity; remote sensing; Environmental sciences; GE1-350; Meteorology. Climatology; QC851-999; Greenland; glacier; Ice Sheet; Journal of Glaciology
• Online Access: https://doi.org/10.1017/jog.2021.89; https://doaj.org/article/b0491171022d47bea131ef40c862b1ec

Greenland glaciers exhibit variable seasonal velocity signals that may reflect differences in subglacial hydrology. Here, we conduct a first GrIS-wide glacier classification based on seasonal velocity patterns derived from 2017 Sentinel-1 radar data. Our classification focuses on two distinct seasonal ice velocity patterns, with the first (type-2 from Moon and others, 2014) showing periods of both speedup and slowdown during the melt season, and the second (type-3) instead showing a longer period of slowdown from elevated velocities in the winter and spring. We analyze 221 glaciers in 2017 and show that 48 exhibit type-2 behavior, and 72 exhibit type-3 behavior. We extend the classification to 2018 and 2019 and find that while the glaciers meeting each criterion vary year to year, type-2 is consistently more common in the northern regions and type-3 is more common in the south. Our results highlight the varied impact of meltwater on subglacial drainage systems and glacier flow in Greenland.