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Marine heatwaves are increasing in intensity and frequency, causing worldwide coral bleaching, reductions in coral cover, and shifts in species composition. Recent studies have found, however, that inshore turbid reefs are more resistant to heat stress than offshore clear-water reefs. Inshore turbid reefs, therefore, may play a critical role as climate-change refuges for contemporary coral reefs subjected to marine heatwaves. This perspective explores the importance of inshore reefs in the past, present, and future. Paleo records show that inshore reefs were also crucial as refuges during historically warm periods. Yet, contemporary inshore reefs are especially vulnerable to pollution and land-use-change runoff, which were absent in paleo times. Therefore, inshore reefs need strategic management and protection to maintain their role as climate-change refugia as the oceans continue to warm. 

Abstract Corals are being increasingly subjected to marine heatwaves. Theory suggests that increasing the intensity of disturbances reduces recovery rates, which inspired us to examine the recovery rates of coral cover following marine heatwaves, cyclones, and other disturbances at 1921 study sites, in 58 countries and three oceans, from 1977 to 2020. In the Atlantic Ocean, coral cover has decreased fourfold since the 1970s, and recovery rates following disturbances have been relatively slow, except in the Antilles. By contrast, reefs in the Pacific and Indian Oceans have maintained coral cover and recovery rates over time. There were positive relationships between rates of coral recovery and prior cyclone and heatwave frequency, and negative relationships between rates of coral recovery and macroalgae cover and distance to shore. A recent increase in the variance in recovery rates in some ecoregions of the Pacific and Indian Oceans suggests that some reefs in those ecoregions may be approaching a phase shift. While marine heatwaves are increasing in intensity and frequency, our results suggest that regional and local conditions influence coral recovery rates, and therefore, effective local management efforts can help reefs recover from disturbances.