Which of the following is the predominant cause of coral bleaching?

The correct answer is Rise in sea temperature.

Key Points

• Coral bleaching primarily occurs when corals expel the symbiotic algae (zooxanthellae) living in their tissues due to stress caused by rising sea temperatures.
• Increased sea temperatures, often linked to global warming, disrupt the delicate balance between corals and algae.
• Corals lose their vibrant color and turn white when the algae are expelled, leading to reduced energy generation for the corals.
• Prolonged exposure to higher temperatures can lead to massive coral mortality, severely impacting marine ecosystems.
• Studies by organizations like NOAA and IPCC have shown that ocean warming due to climate change is the predominant driver of coral bleaching.

Additional Information

• Zooxanthellae: These are symbiotic algae that live within coral tissues and provide energy to corals through photosynthesis.
• Ocean Acidification: While not directly responsible for coral bleaching, increased CO2 levels can weaken coral skeletons, compounding the damage caused by bleaching.
• El Niño Events: These periodic climate phenomena lead to elevated sea temperatures and are often associated with widespread coral bleaching events.
• Marine Ecosystem Impact: Coral reefs support diverse marine life; bleaching events disrupt food chains and biodiversity in affected regions.
• Mitigation Efforts: Reducing greenhouse gas emissions and promoting sustainable marine practices are crucial to preventing further coral bleaching events.