Greenland is melting, especially at the coasts where ice meets the ocean. We know that ice is thinning and receding at the edges, but it’s a lot harder to measure farther inland.
This winter, researchers from Denmark and other countries report a study of one important case, the Northeast Greenland Ice Stream [1]. Using satellite data, remote sensing, and ground receivers, the study estimated the position and movement of the ice stream from 2007 to 2021. This covers the ice stream hundreds of kilometers inland, including the entire length of two ocean terminating glaciers.
The integrated model indicates that the ice is thinning and accelerating faster than earlier models. There was a major event in 2012, when an ice shelf collapsed. This new study shows “that extensive speed-up and thinning triggered by frontal changes in 2012 have already propagated more than 200 km inland”. ([1], p. 727) I.e., when the ice at the ocean disappeared it released the glaciers to flow more quickly. This has had a rapid and detectable impact.
This is further evidence that Greenland’s ice is rapidly melting into the ocean. This will contribute to rising mean sea level. This study calculates that “this marine-based sector alone will contribute 13.5–15.5 mm sea-level rise by 2100 (equivalent to the contribution of the entire ice sheet over the past 50 years)” ([1], p. 727) Overall, they predict much higher sea level changes than previous studies.
This is becoming a pattern. Every new study improves the measurements of the ice, and every new measurement increases the estimates of ice loss. The bottom line is that Greenland is melting really fast, pretty much everywhere. In a few decades, there will be no permanent ice on Greenland at all.
Wow. And, “glub”.
- Kathryn Hansen, Greenland’s largest ice stream is expected to contribute more to sea level rise than models previously indicated, in NASA Earth Observatory – Image of the Day, January 7, 2023. https://earthobservatory.nasa.gov/images/150801/thinning-of-the-northeast-greenland-ice-stream
- Shfaqat A. Khan, Youngmin Choi, Mathieu Morlighem, Eric Rignot, Veit Helm, Angelika Humbert, Jérémie Mouginot, Romain Millan, Kurt H. Kjær, and Anders A. Bjørk, Extensive inland thinning and speed-up of Northeast Greenland Ice Stream. Nature, 611 (7937):727-732, 2022/11/01 2022. https://doi.org/10.1038/s41586-022-05301-z
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