Deglaciation-enhanced mantle CO<sub>2</sub> fluxes at Yellowstone imply positive climate feedback.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38378722.
- Also identified by DOI 10.1038/s41467-024-45890-z and PMC identifier 10879189.
- 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
Mantle melt generation in response to glacial unloading has been linked to enhanced magmatic volatile release in Iceland and global eruptive records. It is unclear whether this process is important in systems lacking evidence of enhanced eruptions. The deglaciation of the Yellowstone ice cap did not observably enhance volcanism, yet Yellowstone emits large volumes of CO<sub>2</sub> due to melt crystallization at depth. Here we model mantle melting and CO<sub>2</sub> release during the deglaciation of Yellowstone (using Iceland as a benchmark). We find mantle melting is enhanced 19-fold during deglaciation, generating an additional 250-620 km<sup>3</sup>. These melts segregate an additional 18-79 Gt of CO<sub>2</sub> from the mantle, representing a ~3-15% increase in the global volcanic CO<sub>2</sub> flux (if degassed immediately). We suggest deglaciation-enhanced mantle melting is important in continental settings with partially molten mantle - including Greenland and West Antarctica - potentially implying positive feedbacks between deglaciation and climate warming.