Regional and global climate risks for reef corals: Incorporating species‐specific vulnerability and exposure to climate hazards

Abstract

Climate change is driving rapid and widespread erosion of the environmental conditions that formerly supported species persistence. Existing projections of climate change typically focus on forecasts of acute environmental anomalies and global extinction risks. The current projections also frequently consider all species within a broad taxonomic group together without differentiating species-specific patterns.Consequently, we still know little about the explicit dimensions of climate risk (i.e., species-specific vulnerability, exposure and hazard) that are vital for predicting future biodiversity responses (e.g., adaptation, migration) and developing management and conservation strategies. Here, we use reef corals as model organisms (n = 741 species) to project the extent of regional and global climate risks of marine organisms into the future. We characterise species-specific vulnerability based on the global geographic range and historical environmental conditions of each coral species within their ranges, and quantify the projected exposure to climate hazard beyond the historical conditions as climate risk. We show that many coral species will experience a complete loss of pre-modern climate analogs at the regional scale and across their entire distributional ranges, and such exposure to hazardous conditions are predicted to pose substantial regional and global climate risks to reef corals. Although highlatitude regions may provide climate refugia for some tropical corals until the mid-21st century, they will not become a universal haven for all corals. Notably, high-latitude specialists and species with small geographic ranges remain particularly vulnerable as they tend to possess limited capacities to avoid climate risks (e.g., via adaptive and migratory responses). Predicted climate risks are amplified substantially under the SSP5-8.5 compared with the SSP1-2.6 scenario, highlighting the need for stringent emission controls. Our projections of both regional and global climate risks offer unique opportunities to facilitate climate action at spatial scales relevant to conservation and management. K E Y W O R D S climate change, climate change vulnerability, climate risk assessment, coral, novel climate | 4141 KIM et al.

Coral assemblages at higher latitudes favor short‐term potential over long‐term performance

“…Yet, our findings emphasize that the winners and losers in coral assemblages exposed to more variable environments cannot be predicted using measures of long-term performance. Moreover, our observed heterogeneity in the short-term demographic characteristics of coral assemblages can help to explain why different assemblages display varying responses to periodic disturbances (Kim et al, 2023). This insight will benefit future predictions into the compositional reassembly of reef communities worldwide under future global change scenarios.…”

A Comprehensive Review of Climatic Threats and Adaptation of Marine Biodiversity

“…Kim et al [44] conducted a comprehensive study of 741 scleractinian coral species from various parts of the world. They found that coral reefs are under immense pressure and vulnerability worldwide.…”

Comparative physiology reveals heat stress disrupts acid–base homeostasis independent of symbiotic state in the model cnidarian Exaiptasia diaphana

“…The world's oceans have absorbed 93% of excess planetary heat from anthropogenic climate change ( Johnson and Lyman, 2020 ), threatening the survival of sessile marine organisms that cannot migrate to cooler climates to avoid increasingly frequent and severe marine heatwaves ( Atkins and Travis, 2010 ; Kim et al, 2023 ; Smith et al, 2023 ). Marine heatwaves have already decimated populations of keystone invertebrates, including notable losses of reef-building corals (scleractinians) ( Hughes et al, 2017 , 2018 ).…”