Climate change: ocean heat waves

The recent hot weather will have severe impacts on the environment:
Futures Forum: Climate change >>> an early spring and upsetting the balance of nature

And it will have equally severe impacts on the marine environment:
Heat Waves As Deadly As Forest Fires Sweep Through World's Oceans | CleanTechnica
Heatwaves sweeping oceans ‘like wildfires’, scientists reveal | Environment | The Guardian

As covered in the National Geographic: 

Ocean heat waves are killing underwater life, threatening biodiversity

The ocean feels heat waves just like the ones on land, and underwater life is struggling to survive them.

BY SARAH GIBBENS
PUBLISHED MARCH 4, 2019

INTENSE HEAT WAVES are bad for human health. They can lead to sometimes deadly conditions like dehydration and stroke. And just like extreme temperatures on land, marine heat waves can drastically alter life under the sea.

A new study published today in Nature Climate Change found that the occurrences of marine heat waves have substantially grown in the past three decades, and it’s becoming clearer how deadly warmer temperatures are for biodiversity.

Marine heat waves are periods when the average water temperature of a given region is exceptionally high. In the past 30 years marine heat wave days have increased by just over 54 percent, a trend the study’s authors found consistent with declines in oceans life.

High-profile marine heat waves like “the blob,” a huge mass of warm water that was present off the U.S. West Coast from 2014-2016, were included in the study. The blob was responsible for massive die-offs of everything from invertebrates to marine mammals.
“It is clear that extreme warming events can drive abrupt changes in entire ecosystems with widespread consequences,” says study author ecologist Daniel Smale.

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Ocean heat waves are killing underwater life, threatening biodiversity 

As shown in this diagram: 

File:Global warming - change in total heat content of earth.jpg - Wikimedia Commons

Meanwhile, as this map from the Economist shows, the Florida Everglades will be particularly badly effected:
Climate change will affect more than the weather - Daily chart

And things in the Tasman Sea are really hotting up, as covered in the Guardian earlier today:
Australia's marine heatwaves provide a glimpse of the new ecological order | Environment | The Guardian 

The Weather Network looked at the issue last summer:
News - Ocean 'heat waves' on the rise, destroying entire ecosystems - The Weather Network
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