Why does coral bleaching cause the corals to die

This would be devastating for coral reefs as they would have no chance to recover. To stop coral bleaching we must stop carbon pollution that is heating our planet and cooking our oceans. We must quit coal and switch to renewables now. Mining and burning coal pollutes the atmosphere and causes global warming.

Increased carbon pollution in our atmosphere traps heat, which causes the temperature to rise on Earth. The higher and longer the temperature, the worse it gets. Ocean heatwaves cause stress for corals. Even a rise of just one degree celsius for only four weeks can trigger bleaching in a coral. If ocean temperatures stay high for eight weeks or longer, the coral cannot recover and begins to die.

Carbon pollution is causing unprecedented damage to our Great Barrier Reef. In recent years, our Reef has suffered severe mass coral bleaching, faster and more severe than scientists predicted.

Over and , our Reef suffered back-to-back bleaching, leaving half of the shallow water corals dead. To compound this, a category four cyclone ravaged the Whitsundays region — decimating coral reefs in its path. A combination of two severe bleaching events, Cyclone Debbie and current outbreaks of coral-eating Crown of Thorns starfish have significantly impacted the health our Great Barrier Reef.

Human beings are incredible when we act together. With real leadership we can stop runaway carbon pollution and allow our coral reefs to recover and rebuild. But to do this, we must quit dirty coal, and transition to renewable energy today. If we take climate leadership then our coral reefs, and the thousands of species that rely on them, can rebuild and thrive for generations to come. Therefore, sustaining and restoring coral reefs should be treated as an asset, and long-term investments should be made for their preservation.

Investments should also include support for research at the frontiers of biology, such as genetic selection of heat-resistant corals that can withstand rising global temperatures. Issues Briefs related to nature conservation and sustainable development often have societal impacts beyond conservation. Heron et al. Obura, D. Science — What is the issue? Why is it important? What can be done?

Last reviewed:. Coral reefs harbour the highest biodiversity of any ecosystem globally and directly support over million people worldwide, mostly in poor countries. They are among the most threatened ecosystems on Earth , largely due to unprecedented global warming and climate changes, combined with growing local pressures.

Over the last three years, reefs around the world have suffered from mass coral bleaching events as a result of the increase in global surface temperature caused by anthropogenic greenhouse gas emissions.

According to UNESCO, the coral reefs in all 29 reef-containing World Heritage sites would cease to exist by the end of this century if we continue to emit greenhouse gases under a business-as-usual scenario. Latest Issues Briefs. Marine heatwaves. Read more about Marine heatwaves. 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 subject to mortality. In , the U. The warm waters centered around the northern Antilles near the Virgin Islands and Puerto Rico expanded southward. Comparison of satellite data from the previous 20 years confirmed that thermal stress from the event was greater than the previous 20 years combined.

In January , cold water temperatures in the Florida Keys caused a coral bleaching event that resulted in some coral death.