Question

Why is some of the coral in the Great Barrier Reef white?

Answer 1

Algae is the main reason for the color of the corals and when algae is not present, the corals become white.

Step-by-step explanation:

The rising temperatures of sea water are the reason why some corals of the Great Barrier Reef are white. Higher temperatures of water cause bleaching of the corals. During bleaching, the corals lose their color because the coral polyps expel the algae that live in them. Algae not only provide color but also energy to the corals and after bleaching they may not be active.

Answer 2

The earth climate is changing and became very hot, and the waters on rivers and oceans are becoming warmer. Corals that live in tropical coral reefs are very sensitive, and they don't survive with big temperature changes. Inside the coral lives a very small alga, that gives the colours and also energy to the corals, with the high temperature of the waters, this algae die, and make the corals lose their colours and if the temperature doesn't return to normal they die.

Step-by-step explanation: