the blob

Beware of the blob

June 20, 2024 By EarthWise Leave a Comment

For the past 10 years, there have been several occurrences of a vast expanse of ocean stretching from Alaska to California in which water temperatures are as much as 7 degrees Fahrenheit warmer than normal. Known jocularly as “the Blob,” the phenomenon can last for several years and decimates fish stocks, starves seabirds, creates blooms of toxic algae, prevents salmon from returning to rivers, and displaces sea lions and whales.

Until recently, there was no accepted explanation for this abrupt ocean heating. Climate change, even combined with natural cycles like El Niños, is not enough to account for it.

In depth analysis by an international team of researchers has found that the extraordinary heating is the result of a dramatic cleanup of Chinese air pollution. The decline of smog particles, which to some extent shield the planet from the sun’s rays, has accelerated warming and set off a chain of atmospheric events across the Pacific, essentially cooking the ocean.

This is an example of what can be called the pollution paradox in which global warming is actually increased when air pollution is reduced. Reduced air pollution on the US West Coast has even been identified as a factor contributing to increased wildfires. However, air pollution causes more than 4 million premature deaths from cancers and respiratory and cardiovascular diseases each year.

Nobody thinks that we should stop cleaning up the air to slow down global warming. The only viable solution is to reduce greenhouse gas emissions as rapidly as possible.

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Pollution Paradox: How Cleaning Up Smog Drives Ocean Warming

Photo, posted December 18, 2017, courtesy of SGUP via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Marine Heat Waves | Earth Wise

August 17, 2023 By EarthWise Leave a Comment

In late July, the ocean temperature measured in Florida Bay, between the southern end of the Florida mainland and the Florida Keys, was 101.1 degrees Fahrenheit, a possible world record for sea surface temperature. There is no official record keeping for ocean temperatures, but the highest previous reading ever reported was 99.7 degrees in the middle of Kuwait Bay in 2020.

What is going on is a marine heat wave and marine heat waves can last for weeks, months, or even years. The current Gulf of Mexico marine heat wave has been present for several months, beginning in February or March. Experimental forecasts by the National Oceanic and Atmospheric Administration say the extreme ocean temperatures in the area may persist through at least October.

The ocean absorbs 90% of the excess heat associated with global warming. Therefore, marine heat waves all over the planet are becoming warmer over time. The current marine heat wave would likely have occurred even without climate change, but because of it, the event is extraordinarily warm.

Marine heat waves cause stress to corals and other marine ecosystems. Exposure to extreme temperatures for long periods of time causes corals to eject the algae that live inside of them, resulting in white or pale coral. This coral bleaching leaves the coral without food and will ultimately kill it.

In general, extreme heat can be destructive and deadly for marine ecosystems. A massive marine heat wave known as “the Blob” took hold in 2013-2016 in the northeastern Pacific Ocean and led to an ecological cascade of fishery collapses, toxic algal blooms, and record numbers of humpback whale entanglements.

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The ongoing marine heat waves in U.S. waters, explained

Photo, posted December 25, 2016, courtesy of Paul Asman and Jill Lenoble via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Collapse of Northern California Kelp Forests | Earth Wise

March 30, 2021 By EarthWise Leave a Comment

For thousands of years, thick canopies of kelp formed an underwater forest spanning the coast of Northern California. Kelp is the cornerstone of a rich subtidal community, providing food and habitat for all sorts of marine creatures. But in recent years, a shocking transformation has occurred. Satellite imagery reveals that the area covered by kelp forests off the coast of Northern California has declined by more than 95%. Only a few small, isolated patches remain.

In a new study, researchers at the University of California Santa Cruz found that the kelp forest decline was an abrupt collapse as opposed to a gradual decline.

According to the study, which was recently published in the journal Communications Biology, kelp forests north of San Francisco were resilient to warming events in the past, like El Niños and marine heatwaves. But the decline of a key sea urchin predator – the sunflower sea star – from sea star wasting disease caused the kelp forests’ resiliency to plummet. Sea urchins are voracious consumers of kelp.

But it was a series of events – not just the sea urchins – that combined to decimate the Northern California kelp forest. A marine heatwave that became known as “the blob” developed in 2014 and moved down the West Coast in 2015. Around the same time, a strong El Niño event developed and brought warmer water up the coast from the south. The warming ocean waters combined with the ravenous sea urchin population resulted in the dramatic decline of kelp.

According to researchers, the prospects for a Northern California kelp forest recovery remain poor unless sea urchin predators return to the ecosystem.

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The collapse of Northern California kelp forests will be hard to reverse

Photo, posted August 13, 2019, courtesy of Sara Hamilton of OSU College of Science via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Beware The Blob

February 1, 2016 By WAMC WEB

There has been plenty of discussion of El Niño, the periodic weather phenomenon in which prevailing easterly winds in the Pacific Ocean weaken, allowing warm water to move eastward and wreak havoc with the weather in North and South America. The current El Niño is a particularly strong one; some say it may be one of the strongest ever and are calling it the “Godzilla El Niño.”

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