Emulating absent land processes reduces carbon budgets in CMIP6 models
Year: 2026
Type: article
Abstract: The Transient Climate Response to cumulative Emissions (TCRE) is the cornerstone of estimates of carbon emissions budgets to future warming targets, characterising the near-linear relationship between the increase in global mean temperature and cumulative emissions of CO 2 . TCRE is derived from highly sophisticated Earth System Models (ESMs) - some, however, lack important processes known to have a large impact on TCRE. Here, we use multiple configurations of UKESM, a full-complexity ESM, to estimate how TCRE of 11 ESMs that participated in Coupled Model Intercomparison Project 6 would change if each included six terrestrial carbon cycle related processes present in UKESM, such as nitrogen limitation of photosynthesis and fire-vegetation interactions. We find that accounting for processes not included in the models increases their TCRE by an average of 21.4% implying a reduction of 16.0% ± 0.8% in the carbon budget for the transition from 1.5 °C to 2 °C.
Language: English
Subfield: Global and Planetary Change
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,490
OpenAlex ID: W7223473157
FWCI:
Cites:
Cited by:
Related to: