Accelerating glacier volume loss on Juneau Icefield driven by hypsometry and melt-accelerating feedbacks.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38956392.
- Also identified by DOI 10.1038/s41467-024-49269-y and PMC identifier 11220083.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Globally, glaciers and icefields contribute significantly to sea level rise. Here we show that ice loss from Juneau Icefield, a plateau icefield in Alaska, accelerated after 2005 AD. Rates of area shrinkage were 5 times faster from 2015-2019 than from 1979-1990. Glacier volume loss remained fairly consistent (0.65-1.01 km<sup>3</sup> a<sup>-1</sup>) from 1770-1979 AD, rising to 3.08-3.72 km<sup>3</sup> a<sup>-1</sup> from 1979-2010, and then doubling after 2010 AD, reaching 5.91 ± 0.80 km<sup>3</sup> a<sup>-1</sup> (2010-2020). Thinning has become pervasive across the icefield plateau since 2005, accompanied by glacier recession and fragmentation. Rising equilibrium line altitudes and increasing ablation across the plateau has driven a series of hypsometrically controlled melt-accelerating feedbacks and resulted in the observed acceleration in mass loss. As glacier thinning on the plateau continues, a mass balance-elevation feedback is likely to inhibit future glacier regrowth, potentially pushing glaciers beyond a dynamic tipping point.