ICESat-2 Meltwater Depth Estimates

ICESat-2 Meltwater Depth Estimates: Application to Surface Melt on Amery Ice Shelf, East Antarctica

Fricker, Helen Amanda (University of California)
Arndt, Philipp (University of California)
Brunt, Kelly M. (NASA Goddard Space Flight Center; University of Maryland)
Datta, Rajashree Tri (NASA Goddard Space Flight Center; University of Maryland)
Fair, Zachary (University of Michigan)
Jasinski, Michael F. (NASA Goddard Space Flight Center)
Kingslake, Jonathan (Lamont-Doherty Earth Observatory)
Magruder, Lori A. (The University of Texas at Austin)
Wouters, B. (TU Delft Physical and Space Geodesy; Universiteit Utrecht)

2021

Surface melting occurs during summer on the Antarctic and Greenland ice sheets, but the volume of stored surface meltwater has been difficult to quantify due to a lack of accurate depth estimates. NASA's ICESat-2 laser altimeter brings a new capability: photons penetrate water and are reflected from both the water and the underlying ice; the difference provides a depth estimate. ICESat-2 sampled Amery Ice Shelf on January 2, 2019 and showed double returns from surface depressions, indicating meltwater. For four melt features, we compared depth estimates from eight algorithms: six based on ICESat-2 and two from coincident Landsat-8 and Sentinel-2 imagery. All algorithms successfully identified surface water at the same locations. Algorithms based on ICESat-2 produced the most accurate depths; the image-based algorithms underestimated depths (by 30%–70%). This implies that ICESat-2 depths can be used to tune image-based algorithms, moving us closer to quantifying stored meltwater volumes across Antarctica and Greenland.

Antarctica
Greenland
ICESat-2
ice shelves
surface melt

http://resolver.tudelft.nl/uuid:81dd6d2b-c733-44e0-b36a-69d1ef7e9ac7

https://doi.org/10.1029/2020GL090550

2021-10-28

0094-8276

Geophysical Research Letters, 48 (8)

Institutional Repository

journal article

© 2021 Helen Amanda Fricker, Philipp Arndt, Kelly M. Brunt, Rajashree Tri Datta, Zachary Fair, Michael F. Jasinski, Jonathan Kingslake, Lori A. Magruder, B. Wouters, More Authors