In a promising turn of events for marine conservation, recent satellite imagery has revealed that coral reefs occupy a significantly larger portion of the Earth than previously estimated. This discovery brings a glimmer of hope to the narrative surrounding these vital ecosystems, which have long been under threat.
Coral reefs, constructed by stony corals, are vibrant and diverse ecosystems that thrive in nutrient-poor tropical waters. They are highly sensitive to changes in water conditions, making them vulnerable to threats such as overtourism, pollution, and global warming. Despite these challenges, new data suggests that coral reefs are more widespread than we had realized.
Researchers Mitchell Lyons and Stuart Phinn, based in Queensland, have focused their careers on monitoring and detecting changes in terrestrial and marine ecosystems. Utilizing a combination of satellite imagery and machine learning, their recent studies have uncovered that coral reefs cover at least 25% more of the Earth’s surface than previously thought.
Their groundbreaking research has identified an additional 64,000 square kilometers (24,711 square miles) of coral reefs, an area comparable to the size of Ireland. This discovery increases the known global coverage of coral reefs to 348,000 square kilometers (134,364 square miles), roughly equivalent to the size of Germany.
Although this expanded area represents only 0.1% of the world’s oceans, coral reefs are home to an estimated 25-40% of all marine species, underscoring their critical role in marine biodiversity. These ecosystems are essential for nutrient cycling, carbon fixation, shoreline protection, and providing food and livelihoods for millions of people globally.
This revelation is part of the larger Allen Coral Atlas project, which aims to compile comprehensive data to aid in the protection and preservation of coral reefs. Previously, obtaining accurate data on coral reef coverage required integrating information from multiple sources. Advances in satellite imaging technology now allow for high-resolution images of coral reefs at depths of up to 30 meters (98 feet).
By combining these satellite images with direct observations and records from over 400 individuals and organizations, scientists can now more accurately assess the extent of coral reef ecosystems worldwide. This improved understanding is a significant step forward in the effort to conserve these crucial marine habitats.
