Scientists Fear 'Super El Nino' Could Accelerate Global Coral Bleaching

Scientists have warned that a potentially strong El Nino event this year could deal a devastating blow to coral reefs worldwide, which are already reeling from successive bleaching events. AFP reports that forecasters are increasingly confident that El Nino will return mid-year and could be exceptionally intense. El Nino occurs every two to seven years, altering normal climate patterns and causing droughts in some areas and heavy rainfall in others. This weather phenomenon is also linked to rising sea temperatures and reduced cloud cover, both of which are bad news for global coral reefs. Clint Oakley, a coral reef expert at Victoria University of Wellington, New Zealand, points out that "every global coral bleaching event has occurred during an El Nino year." He admits to feeling "dread, but not surprise" at the prospect of a strong El Nino, as it could bring a "severe, devastating blow" to many of the world's coral reefs. Corals rely on a special symbiotic relationship with algae, which provide nutrients to their hosts through photosynthesis. Scientists still do not fully understand why this relationship breaks down when sea temperatures are too high, causing the algae to leave or be expelled. The algae also give corals their vibrant colors. Once the algae are gone, the coral is left with only a pale skeleton and will gradually starve to death. Jen Matthews, a scholar at the University of Technology Sydney, explains, "If the water temperature doesn't drop fast enough, or if the heatwave is too severe, the coral basically dies of starvation." According to reports, local, periodic bleaching was originally a natural and healthy process. The problem is that climate change is warming the oceans, making large-scale, repeated bleaching the new normal. The last global mass bleaching event was in 2024. Some coral species in the Caribbean are now "functionally extinct," and between 2024 and 2025, coral cover in different parts of Australia's Great Barrier Reef has declined by 15% to 40%.