Thwaites Glacier, Antarctica, is of particular concern to scientists. Here, warm water is pushed up onto the continental shelf, where it flows along the bottom until it reaches the floating ice shelf in front of Thwaites Glacier.
Thwaites Glacier today is rapidly losing mass in response to changing atmospheric and oceanic conditions.
The ice shelf is thinning rapidly and the grounding line is retreating. Below is a schematic figure of an ice shelf and a grounding line.
The ice stream is at risk of greatly accelerated mass loss, as ocean-driven melting at the grounding zone and nearby areas leads to thinning, faster flow and retreat (Scambos et al., 2017) through the process of marine ice sheet instability.
This video explains why the ice stream is changing so rapidly, and what this means in terms of sea level rise.
Scambos, T. A., Bell, R. E., Alley, R. B., Anandakrishnan, S., Bromwich, D. H., Brunt, K., … Yager, P. L. (2017). How much, how fast?: A science review and outlook for research on the instability of Antarctica’s Thwaites Glacier in the 21st century. Global and Planetary Change, 153, 16–34. https://doi.org/https://doi.org/10.1016/j.gloplacha.2017.04.008