Climate Crisis Intensifies Deadly Coral Bleaching Event
As the world continues to warm, there has been a notable increase in coral bleaching events, posing a significant threat to crucial marine ecosystems over the past decade. Recently, the US National Oceanic and Atmospheric Administration (NOAA) confirmed that the world is experiencing its fourth global bleaching record.
Normally corals have a symbiotic relationship with zooxanthellae algae which lives inside their tissue. These algae are the primary source of food for the corals. when corals are exposed to changing conditions such as temperature, nutrients and light they become stressed and they expel the symbiotic algae within them and turn white in color. This is called coral bleaching. When a coral bleaches, it is not dead. Corals can survive a bleaching event, but they are under more stress and are most likely to die away.
Coral reefs support diverse and abundant marine life, serving as important habitats for fish, shellfish, and other species that local communities rely on for food and livelihoods and they provide a huge value to the economy. According to the “Status of Coral Reefs of the World: 2020” report , The value of goods and services provided by coral reefs is estimated at US$2.7 trillion per year, including US$36 billion in coral reef tourism.
The Great Barrier Reef experienced its first major bleaching event in 1998, marking the beginning of a troubling trend. Since then, bleaching events have become increasingly frequent. In 2023, the Earth recorded its hottest year on record, with El Niño playing a significant role in this anomaly. The 2014–2017 El Niño event stands out as the longest on record, causing widespread damage to coral reefs. This global mass bleaching event was particularly devastating, impacting over 70% of our coral reefs.
It is anticipated that many coral reefs will undergo irreversible phase shifts due to marine heatwaves, especially with global warming levels exceeding 1.5°C. However, there is hope on the horizon. As we transition from the current El Niño to a cooler La Niña this summer, we expect a temporary decline in the percentage of reef areas being impacted. Its high time that we get serious about slashing our greenhouse gas emissions. It’s the only way to put the brakes on ocean warming and give our remaining reefs a fighting chance.
