From Tallbloke’s Talkshop
February 22, 2023 by oldbrew
Alaskan permafrost: [image credit: insideclimatenews.org]
Nature has its own adaptations. Eventually the process, should it occur, becomes self-limiting.
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Oak Ridge National Laboratory scientists set out to address one of the biggest uncertainties about how carbon-rich permafrost will respond to gradual sinking of the land surface as temperatures rise.
Using a high-performance computer simulation, the research team found that soil subsidence is unlikely to cause rampant thawing in the future, says EurekAlert.
The United Nation’s Intergovernmental Panel on Climate Change has identified the possibility of soil subsidence leading to a feedback loop that could trigger a rapid thaw as a major concern in the decades ahead.
Accelerated thawing caused by uneven land subsidence has been observed on smaller scales over shorter time frames, but the IPCC’s assessments were uncertain as to what may happen over the long term.
That’s where ORNL stepped in with its Advanced Terrestrial Simulator, or ATS, a highly accurate, physics-based model of the region’s hydrology fed by detailed, real-world measurements to help scientists understand the land’s evolution.
What they found is that even though the ground will continue to sink as big ice deposits melt, the uneven subsidence also leads to a drier landscape and limits the process’s acceleration through the end of the century, as described in the Proceedings of the National Academy of Sciences.
“Improved drainage results in a drier landscape over a decadal timescale, and the process then becomes self-limiting,” said Scott Painter, who leads the Watershed Systems Modeling group at ORNL.
Full article here.