There is high confidence in the existence of threshold behaviour of the Greenland Ice Sheet in a warmer climate ; however, there is low agreement on the nature of the thresholds and the associated tipping points. Similarly, the likelihood for accelerated and irreversible mass loss from Antarctica increases with increasing temperatures, but thresholds cannot yet be unambiguously identified. By the year 2100, sea level projections ) now range from 0.57 m  for the SSP1-1.9 scenario to 1.35 m  for the SS5-8.5 scenario and become 1.99 m for the latter scenario  in the case of low-likelihood, high-impact outcomes resulting from ice sheet instability, for which there is limited evidence. It should be noted that inclusion of such low-likelihood, high-impact outcomes dominated by not-well-understood processes affecting ice dynamics on the large ice caps of Greenland, and in particular Antarctica, would also enhance the sea level projections for other scenarios, but to a lesser extent for increasingly weaker forcing. No quantitative assessment of their effect in other scenarios than SSP5-8.5 yet exists as such simulations with ice sheet models have not been carried out, or only in a very limited amount.
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report