Future of the Environment

A giant marine heatwave has descended on Alaska

A couple sit on the sand watching the sun set on the Pacific Ocean in Cardiff, California September 27, 2015.  REUTERS/Mike Blake - GF10000224609

This warming has an affect of more than 2.7°C in the waters off the coast of Washington state Image: REUTERS/Mike Blake

Sean Fleming
Senior Writer, Formative Content
Our Impact
What's the World Economic Forum doing to accelerate action on Future of the Environment?
The Big Picture
Explore and monitor how Future of the Environment is affecting economies, industries and global issues
A hand holding a looking glass by a lake
Crowdsource Innovation
Get involved with our crowdsourced digital platform to deliver impact at scale
Stay up to date:

Future of the Environment

An area of unusually warm water is growing off the west coast of North America, stretching from Alaska and Canada to California.

It’s the second largest marine heatwave of its kind, according to the US National Oceanic and Atmospheric Administration (NOAA). The largest was in 2014: nicknamed “the Blob,” it covered an area from Mexico to Alaska.

The 2014 event was blamed for sparking warmer weather on land, depleting salmon food stocks and causing the sudden deaths of around 30 whales in the Pacific. Those deaths were most likely to have been brought on by the whales ingesting toxic algae, created by the warming ocean. Back then, temperatures in the water peaked at 3.9°C above average.


What's the World Economic Forum doing about the ocean?

Return of ‘the Blob’?

So far, this year’s “Blob” – officially known as the Northeast Pacific Marine Heatwave of 2019, or NEP19 – has had a warming effect of more than 2.7°C in the waters off the coast of Washington state.

Andrew Leising and Steven Bograd, research scientists at NOAA Fisheries’ Southwest Fisheries Science Center in California, are tracking and measuring the heatwave.

“Coastal upwelling of deep, cold water has kept the warm expanse mostly offshore, although it appears to have come ashore in Washington and could do so in other areas as upwelling wanes in the fall,” they say. “If atmospheric conditions persist and NEP19 moves into nearshore coastal waters, it is likely to have impacts on coastal ecosystems this fall.”

The enormous area covered by “the Blob” and its reincarnation, NEP19.
Image: NOAA

The NOAA believes the marine heatwave started when a ridge of high pressure weakened winds that would normally have cooled the surface temperature of the ocean. It says the size and scale of NEP19 could rival the 2014 Blob.

The agency also highlights a pattern of warmer water that could indicate longer-term changes to the marine climate. It has identified a band of unusually warm high pressure stretching north to the Bering Sea and Alaska in recent years.

Real and present danger

“Given the magnitude of what we saw last time, we want to know if this evolves on a similar path,” says Chris Harvey, a research scientist at the NOAA’s Northwest Fisheries Science Center.


What is the World Economic Forum’s Sustainable Development Impact summit?

Coastal waters are important marine ecosystems – feeding and breeding grounds for thousands of different animals. Their habitat is at risk of being damaged by NEP19, repeating what happened in 2014.

But the threat posed by warming oceans across the globe is even greater than that.

Approximately half of all our oxygen is generated by phytoplankton – tiny plant-like organisms that live in the ocean. They also consume carbon dioxide, transferring about 10 gigatonnes of carbon from the atmosphere deep into the ocean each year.

Anything that disrupts life for the phytoplankton could easily disrupt our lives too.

Warming seas are also believed to be responsible for coral bleaching, wiping out all life across entire reefs. Added to which, warming oceans can start to create a vicious cycle of associated problems – greater and more volatile storms, increased deoxygenation, and more.

Have you read?
Don't miss any update on this topic

Create a free account and access your personalized content collection with our latest publications and analyses.

Sign up for free

License and Republishing

World Economic Forum articles may be republished in accordance with the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Public License, and in accordance with our Terms of Use.

The views expressed in this article are those of the author alone and not the World Economic Forum.

World Economic Forum logo
Global Agenda

The Agenda Weekly

A weekly update of the most important issues driving the global agenda

Subscribe today

You can unsubscribe at any time using the link in our emails. For more details, review our privacy policy.

Why protecting the ocean floor matters for climate change

William Austin

April 17, 2024

About Us



Partners & Members

  • Join Us

Language Editions

Privacy Policy & Terms of Service

© 2024 World Economic Forum