2023–2025 global coral bleaching event

High school (ages 12+)
Environment & Earth

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/2023-2025-global-coral-bleaching-event

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the event timeline?February 2023 – ongoing (as of April 2025 declaration)
2. What is the percentage of reefs affected?Approximately 84% of Earth's coral reef ecosystems
3. What is coral bleaching and why does it happen?When ocean water gets too hot, the tiny algae that live inside coral leave, making the coral look white.
4. How many coral reefs were affected by the 2023‑2025 bleaching event?About 84% of the world's coral reefs were affected, and reefs in at least 82 countries turned white.

Coral Bleaching: The expulsion of symbiotic zooxanthellae from coral tissues due to environmental stressors, primarily elevated sea temperatures, leading to loss of color and energy source.
Anthropogenic Climate Change: Global climate shifts driven by human activities, predominantly the emission of greenhouse gases from fossil fuel combustion, deforestation, and industrial processes.
Zooxanthellae: Microscopic symbiotic algae that live within the tissues of corals, providing them with essential nutrients and their characteristic coloration.