Many studies have proposed biodiversity hotspots based on different criteria, taxa and geographic contexts . A coherent comparative assessment of all such schemes is beyond the scope of this chapter but is provided in recent reviews . We base this assessment on the 'WWF Global 200' areas of conservation importance . These 238 ecoregions have been used in a previous climate risk assessment  and cover terrestrial, freshwater and marine environments . In addition, we included terrestrial 'biodiversity hotspots' as defined by Myers et al.  and extended later . This assessment thus covers the 'Global 200'  and 'Myers' biodiversity hotspots, rather than particular species or ecological systems, such as rainforests, coral reefs or the deep sea. Such systems are assessed in Chapters 2 and 3. Chapters 2 and 3 also cover observed and projected impacts, changes in ecosystem functioning, and species extinction risks at a global level.
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report