Projected increases in exposure to climate extremes across global vertebrate diversity hotspots

Climate change intensifies climate extremes globally, threatening
biodiversity. Vertebrates vulnerable to climate extremes are identified by
the International Union for Conservation of Nature (IUCN), though future
changes in exposure to climate extremes for these species remain unclear.
Using CMIP6 climate models under four Shared Socio-economic Pathways, we
projected changes in extreme drought, heat, and precipitation frequencies
globally between 1974–2014 and 2050–2090 for 1,634 terrestrial vertebrates
considered threatened by climate extremes, focusing on 33 global
vertebrate diversity hotspots. Results indicate substantial increases in
climate extremes, with tropical regions facing the highest increases in
extreme heat and drought. Hotspots with few climate extreme-threatened
vertebrates often face the highest increases in climate extreme
frequencies, suggesting vertebrate vulnerability within numerous hotspots
is understudied. These results highlight the need to incorporate climate
projections into conservation assessments, and for targeted research on
climate extreme effects on tropical vertebrates, which may have lower
tolerances to climatic change than temperate counterparts.