How is climate change affecting coral reefs?

According to the Environmental Protection Agency (EPA), ocean surface temperatures have risen sharply in the 20th century and risen. In fact, the average temperature increase between 1901 and 2015 has been at 0.13 degrees Fahrenheit per decade. That may not sound like much, at least not year to year, but it can certainly make a difference to the delicate creatures that call the ocean their home.

According to NOAA Climate.gov, the ocean is one of the largest heat collectors in the world. It is spacious, reflective, and completely out of sight of the sun. Decreased ozone levels have allowed more sun to enter, melting the polar ice caps and raising sea levels. But more ocean does not mean less warmth. If anything, it means there is now more surface to hit the sun, and in subtropical and tropical areas, that heat can produce more environmental impacts.

Corals like warm water, that’s true, but extremely warm waters endanger the health of the corals. If the corals die, the diverse communities and ecosystems that live around them begin to break down. Corals also leach pollutants and dirt from the water, if they are not there to do so, water quality will decline. Worse water quality means fewer plankton, which means fewer fish and other creatures that could have fed that plankton. But less fish also means fewer people, as many coastal cultures depend on fishing for their sustenance and livelihood.

Rising sea temperatures can cause coral swelling, which is when corals release algae, which causes the coral to change from their normal vibrant color scheme to a bright white, according to the National Oceanic Service. Blowing coral will not actually kill corals, but it will make them more prone to death (and the species that depend on coral reefs).