Model projections suggest a reduction of permafrost extent and potentially large carbon losses for all warming scenarios . Already a mean temperature increase of 2ºC could reduce the total permafrost area extent by about 5-20% by 2100 . Associated CO2 losses in the order of 15 Gt up to nearly 70 Gt by 2100 have been projected across a number of modelling studies . Limiting the global temperature increase to 1.5ºC versus 2ºC could reduce projected permafrost CO2 losses by 2100 by 24.2 Gt  . Losses are possibly underestimated in the studies that consider only the upper permafrost layers. Likewise, the actual committed carbon loss may well be larger  due to the long time scale of warming in deep permafrost layers . It is not known at which level of global warming an abrupt permafrost collapse  compared to gradual thaw  would have to be considered an important additional risk. Large uncertainties arise also from interactions with changes in surface hydrology and/or northward migrating woody vegetation as climate warms, which could dampen or even reverse projected net carbon losses in some regions . Overall, there is low confidence on how carbon-permafrost interactions will affect future carbon cycle and climate, although net carbon losses and thus positive  feedbacks are likely  . See also WGI AR6  for a discussion on impacts of higher-emission and warming scenarios.
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report