It looks like the increase in CO[sub]2[/sub] in the atmosphere is having a negative effect on coral reefs. CO[sub]2[/sub] reacts with water to form Carbonic Acid, which means that the increase of CO[sub]2[/sub] makes the oceans more acidic. Coral is not able to handle the increase in acidity because the polyps anchor onto limestone, which dissolves in acid solutions (and the ocean is one big solution).
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