Climate Threats and Management
The combination of global climate change and local threats has resulted in major declines in coral reef ecosystems worldwide. Global assessments indicate that more than 50% of the world’s corals may have been lost over the past 30 years, ref including a documented 14% decline in global live coral cover during the 2010s, ref with additional losses expected following the fourth global mass bleaching event in 2023-2025. Corals are now listed as “most at risk of extinction” by the Convention on Biological Diversity, ref and are approaching climate tipping-points where most coral reefs globally are likely to experience long-term degradation as temperatures reach and exceed +1.5 °C of warming. ref
Such losses have catastrophic repercussions on the services coral reefs provide and the people they support, reflecting not just a biodiversity crisis, but also a social, cultural, and economic challenge. Fortunately, scientists, conservationists, and environmental managers across the globe are developing and implementing new strategies to protect and conserve these ecosystems against a suite of local and global threats.
Climate threats affect all reefs regions of the world. They are mostly linked to increase sea-surface temperatures and associated mass coral bleaching, but also include changes in ocean chemistry, tropical storms patterns and sea level rise. This toolkit provides information on climate threats to coral reefs, their ecological and socio-economic impacts, and existing management strategies. For more in-depth information, take the Coral Reef Management Online Course Lesson 2: Threats to Coral Reefs and Lesson 3: Management Strategies for Resilience.
Two different species of corals experiencing varying levels of resistance to bleaching. Photo © The Ocean Agency