The concept of temperature overshoot, defined as 'exceedance of a specified global warming level followed by a decline to or below that level during a specified period of time' is a relevant consideration for this RFC risk assessment; however, the effect of overshoot has not explicitly been considered in the burning ember assessment because of the limited literature basis. However, despite the lack of directly assessed overshoot scenarios, the current literature provides several salient examples of irreversible changes that are projected to occur once global temperatures reach a particular level. For example, coral reefs are unable to survive repeated bleaching events that are too close together, leading to irreversible loss of the reefs even if bleaching were to cease . Species extinction is irreversible, and Chapter 2 assesses that, at ~1.6℃, >10% of species are projected to become endangered as compared with >20% at ~2.1℃ ,
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report