mortality  has caused the mortality of up to 20% of trees in western North America, the African Sahel, and North Africa, linked to a warming of 0.3-0.9℃ above pre-industrial levels, and is implicated in more than 100 other cases of drought-induced tree mortality in Africa, Asia, Australia, Europe, and North and South America . Species in biodiversity hotspots already show changes in response to climate change . Román-Palacios and Wiens  attribute local extinctions of several taxonomic groups between the latter 20th century and 2003-2012,  to climate-change-related temperature extremes for up to 44%  of species. Widespread declines of up to 35% in the species richness of the unique pollinator group, bumble bees, between 1901-1974 and 2000-2014 are also attributed to climate change, via increasing exceedance of their thermal tolerance limits across Europe and North America . The first extinctions attributed to climate change have been now detected with the present 1.2°℃ warming, including that of the Bramble Cay melomys , a sub- species of the lemuroid ringtail possum , and golden toad  . An increasing frequency or unprecedented occurrence of mass animal mortality due to climate- change-enhanced heatwaves has also been observed in recent years on more than one continent, including temperature-vulnerable terrestrial birds and mammals in South Africa and Australia . There have also been 90% declines in sea- ice-dependent species such as sea lions and penguins in the Antarctic . A strong effect of climate change on the observed contraction of ranges of polar fish species and strong expansion of ranges of arcto-boreal or boreal fish was observed between 2004 and 2012 . Even if current human-driven habitat loss is excluded, many hotspots are projected to cease to be refugia , at 1.0-1.5℃ .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report