Timescales of the permafrost carbon cycle and legacy effects of temperature overshoot scenarios.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 33976172.
- Also identified by DOI 10.1038/s41467-021-23010-5 and PMC identifier 8113593.
- 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
Minimizing the risks and impacts of climate change requires limiting the global temperature increase to 1.5 °C above preindustrial levels, while the difficulty of reducing carbon emissions at the necessary rate increases the likelihood of temporarily overshooting this climate target. Using simulations with the land surface model JSBACH, we show that it takes high-latitude ecosystems and the state of permafrost-affected soils several centuries to adjust to the atmospheric conditions that arise at the 1.5 °C-target. Here, a temporary warming of the Arctic entails important legacy effects and we show that feedbacks between water-, energy- and carbon cycles allow for multiple steady-states in permafrost regions, which differ with respect to the physical state of the soil, the soil carbon concentrations and the terrestrial carbon uptake and -release. The steady-states depend on the soil organic matter content at the point of climate stabilization, which is significantly affected by an overshoot-induced soil carbon loss.