An Ocean Too Hot For Coral Reefs

Coral reefs aren’t just beautiful: they support 25% of all marine animals and the livelihoods of 500 million people, through fishing and tourism.

Coral reefs die when the ocean gets too hot: first they turn white, called coral bleaching, which is like going into a coma. Then they die completely. Corals are barely surviving in today’s warmer ocean. It’s 1.5 degrees F warmer than it was 40 years ago, and 90% of the Barrier Reef just bleach, as did 47% of Hawaii’s reef. In 2040 when the ocean is another 1.5 degrees warmer, 99% of corals will bleach every single year.

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A Hotter Ocean Is Killing Coral Reefs

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How is the earth getting warmer?

Carbon emissions from cars and factories build up in the atmosphere that surround the earth, like a blanked. They trap heat from leaving escaping the earth, warming the earth. With more carbon, the blanket gets thicker and traps more heat.

Carbon can stay up in the air for hundreds of years, so this blanket keeps heating the earth for centuries, even after we stop releasing pollution into the air.

 

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Carbon can stay up in the air for hundreds of years, so this blanket keeps heating the earth for centuries, even after we stop releasing pollution into the air.

 

Is this climate change natural?

The warming seen over the last century has both natural and human sources, and scientists can tell them apart. Scientists can predict what warming we’d see if it had only natural causes, or if it had human causes from carbon emissions. The temperatures we’ve seen in the last 100 years match up with human causes, which are causing most of the warming.

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How much hotter will it get?

Exactly how much hotter will the world get? That depends on what we do next, and how hard we try to reduce carbon emissions, and move to clean energy. Actions America takes now, as a country and as a world leader, will shape just how hot the future gets.  Here are the scenarios:

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Governments across the world have set a target of staying below 3.6 F to avoid the worst climate change, but that goal is not attainable, as the world races towards the carbon emission threshold of 450 PPM in 2030.

On our current path the whole world would warm to 6.5 F by 2100 and keep getting warmer, putting us at risk of the worst consequences of global warming. Heroic effort for clean energy could keep reduce warming and its impacts, 4.5 F. That’s twice the warming we’ve experienced today.

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