Coastal bleaching refers to the whitening and degradation of coral reefs and other calcifying marine organisms in coastal ecosystems due to the loss of symbiotic algae (zooxanthellae) or the deterioration of biological productivity. Coral reefs are among the most productive marine ecosystems, supporting immense biodiversity, fisheries, tourism, and coastal protection. Bleaching is a stress response that weakens corals and, if prolonged, results in widespread mortality. The increasing frequency and intensity of bleaching events have made it a major concern in oceanography and marine conservation. The primary cause of coastal bleaching is the rise in sea surface temperature associated with global climate change. Corals have a narrow thermal tolerance, and even an increase of 1–2°C above the long-term summer average can disrupt the symbiotic relationship between corals and zooxanthellae. Under thermal stress, corals expel these algae, exposing their white calcium carbonate skeletons. Without zooxanthellae, corals lose their primary source of energy and become highly vulnerable to disease and starvation. Ocean warming is further intensified by marine heatwaves, which have become more frequent and prolonged due to anthropogenic greenhouse gas emissions. Extended periods of unusually warm water create severe bleaching events affecting large stretches of coastline. Repeated heat stress reduces the recovery capacity of coral reefs and accelerates ecosystem degradation. Ocean acidification is another important factor contributing to coastal