What impact do marine heatwaves have on coral reefs?

Question

Accepted Answer

Marine Heatwaves Cause Coral Bleaching and Death

Marine heatwaves, characterized by prolonged periods of unusually high sea temperatures, have a detrimental impact on coral reefs, leading to bleaching and ultimately death. These extreme temperature events stress corals, causing them to expel the symbiotic algae that provide them with colour and nutrients. If these conditions persist, the corals are unable to recover and perish.
Widespread Marine Heatwaves Observed

The first six months of the year saw widespread marine heatwaves affecting approximately 82 per cent of the world's oceans. This extent is second only to the records observed in 2024. Such prolonged periods of elevated sea temperatures are a direct threat to marine ecosystems, including sensitive coral formations.
Coral Bleaching and Mortality Mechanism

When sea temperatures rise significantly above average for extended durations, corals experience thermal stress. This stress causes the corals to expel their zooxanthellae, the microscopic algae living within their tissues. The loss of these algae results in the corals turning white, a phenomenon known as coral bleaching.
Long-Term Consequences for Reefs

While corals can recover from mild or short-lived bleaching events, prolonged marine heatwaves can prove fatal. If temperatures do not return to normal levels within a sufficient timeframe, the bleached corals are unable to regain their symbiotic algae and eventually die. This can lead to the degradation and loss of entire reef systems, impacting biodiversity and the coastal communities that depend on them.

Reading history

Hide →

This history is cleared when the page is closed.

What impact do marine heatwaves have on coral reefs?

Loading

Was this article helpful?

Helpful

Not helpful

Report an issue

1

0

0

Share with friends