From the linked paper describing the radiative balance calculations (note we are currently still in the highest emission scenario used in these models):
https://gmd.copernicus.org/articles/13/3571/2020/
> "Here, we include a representation of permafrost feedbacks based on the MAGICC permafrost (Schneider von Deimling et al., 2012), leading to additional cumulative CO2 emissions of 25 to 88 GtC by 2100, 42 to 378 GtC by 2200, and 51 to 542 GtC by 2300 for the lowest (SSP1-1.9) and highest (SSP5-8.5) scenario, respectively (Table 2). Thus, our permafrost module is in line with the IPCC Special Report on 1.5 ∘C warming assumptions for the lowest scenarios (25 GtC versus 27 GtC). While we do not entertain the probabilistic version in this study, our default settings are comparable to the median values reported in Schneider von Deimling (2012). In the highest scenarios (SSP5-8.5), these permafrost-related Earth system feedbacks cause CO2 concentrations that are up to 200 ppm higher by 2200 (Fig. 3a)."