SEALIFE EXTINCTION UNDERWAY ~ Global Warming and Oxygen Deprivation Becoming Worse

by Diana Gooding on May 1, 2022

Marine extinction rebellion to warn and protest

The Current Rate of Ocean Warming May Bring the Greatest Extinction of Sealife in 250 Million Years

From an Article by Bob Berwyn, Inside Climate News, April 28, 2022

A new study suggests that warming, oxygen-starved seas could lead marine species to vanish at a rate matching the planet’s biggest extinction event on record.

If greenhouse gas pollution remains unchecked, global warming could trigger the most catastrophic extinction of ocean species since the end of the Permian age, about 250 million years ago, scientists warned in a new study today. During the end-Permian Extinction, researchers estimate up to 90 percent of marine organisms died out in overheated, acidic and deoxygenated oceans.

The Great Dying, as it’s sometimes called, the worst known mass extinction event in the history of the Earth, wiped out more than half of all biological families, including more than 70 percent of land-dwelling vertebrates, leaving a clear mark in the fossil record.

That cataclysmic change may have resulted from giant volcanic eruptions that went on for 2 million years. But a 2021 study suggested that carbon dioxide emissions from current human activity are twice as high as those that caused the Permian climate to shift.

Ocean temperatures and oxygen levels are already approaching deadly thresholds for some organisms, such as corals and Arctic cod, and potentially threaten thousands more species, said Curtis Deutsch, a Princeton University geoscientist who co-authored the new research published on Thursday in Science.

One of the reasons the researchers chose the Permian extinction as a basis for comparison was that its causes “seemed most clearly related to the kind of climate changes we are seeing now,” he said. “There were enough important similarities, the CO2-driven warming, the loss of oxygen, and the big response in the marine biosphere, that it seemed like the right comparison to start with.”

Additionally, the researchers wanted to measure their results against “the clearest, biggest magnitude of signal in the geologic record,” he said. “When you think about 90 percent of ocean species disappearing, it’s extreme.”

Extinction is Hard to Measure

Human impacts, including global warming, may have already triggered a sixth mass extinction of an as-yet to be determined scope. Just in the last few years, there have been the first documented climate extinctions of species, like a tiny Australian rodent believed to have died out in 2019, and global waves of mass amphibian and insect die-offs. A study published this week in Nature reported that 21 percent of reptiles are threatened with extinction.

But uncertainty about the total number of species on the planet makes it hard to calculate the magnitude of the recent die-offs as compared to past extinctions. If the starting quantity is unknown, it’s hard to measure what’s being lost.

Tracking extinctions in the oceans is even harder. The National Oceanic and Atmospheric Administration, one of the world’s top ocean research institutions, states it is impossible to know the exact number of species that live there because more than 80 percent of the oceans are unobserved and unexplored.

To overcome those challenges, Curtis Deutsch and study co-author Justin Penn, a geoscientist at Princeton University, used a decades-long database of marine animals’ tolerance of warming water and decreasing oxygen. With that data, they created 10 groups of simulated marine species types with similar tolerance characteristics to create a global biogeography of marine life, and modeled how different levels of warming will change the distribution of species and potentially wipe some out.

They chose two very different emissions scenarios to show that today’s climate policy choices will make a big difference in the long run, Deutsch said. A high emissions path with up to 4 degrees Celsius warming by 2100 leads toward a mass extinction of ocean species that “would leave a clearly visible mark on the fossil record,” he said. But the path delineated by the Paris Agreement, keeping warming to between 1.5 and 2 degrees Celsius, could avert the devastation of ocean biodiversity. “We can pretty much avoid a mass extinction,” he said. “It’s not going to look like a biotic collapse in the fossil record.”

Some climate scientists have recently questioned whether the high emissions scenario is still a useful metric. Rapid growth of renewable energy and new government and business promises to reduce emissions could hold warming to about 2 degrees Celsius by the end of the century, but policies to make that happen are still not in place.

Global greenhouse gas concentrations are reaching new record levels each year, and Deutsch said that, given the political and economic uncertainties highlighted by events like the invasion of Ukraine, the possibility that diplomatic efforts to curb warming could fizzle can’t be ruled out.

Malin Pinsky, a Rutgers ecologist and evolutionary biologist who wrote a Perspective article about the new research by Deutsch and Penn, said global policy choices the last few decades have already prompted massive and rapid ocean changes, such as sea level rise, ocean acidification and global shifts of species, which are affecting food security in developing countries. More than half of all human-caused CO2 produced since 1750 have been emitted in just the last 30 years.

“We already know marine life is on the front lines, with species moving faster toward the poles than on land,” he said, citing the black sea bass, a fish species that has moved from offshore Virginia to offshore New Jersey in just a few decades. “It’s part of a massive reorganization of life on earth, and this paper really does a nice job of making clear the stark choices in front of us,” he said.

The findings are important and sobering, said Michael Burrows, a marine ecologist with the Scottish Association for Marine Science, who was not involved in the study. Projecting long-term changes in dynamic and naturally variable ocean ecosystems for which there is very little monitoring is tough to begin with, Burrows said, and “a big problem with such projections, based on the present-day associations between species occurrence and climate (usually temperatures), is that the future climate conditions don’t exist anywhere on Earth right now.”

But biodiversity has responded to climatic changes of similar magnitude in the past, he said. “By showing that their model of projected losses produces changes similar to that seen in past mass extinctions associated with similar climatic changes, the research has resulted in a more credible forecast of the upcoming extinctions due to anthropogenic climate change,” he said.

Has It Already Started?

Oceans have absorbed more than 90 percent of the excess heat trapped on the Earth’s surface by greenhouse gas pollution, building up at a rate equivalent to five atom bomb explosions per second. The average ocean temperature has reached record highs almost yearly, and its surface waters have grown 30 percent more acidic in the past 200 years.

Hot water is already killing marine life, and has perhaps already resulted in extinctions of regionally endemic species, especially during extreme events like marine heat waves. There’s not enough data to know if the sixth great extinction is already underway in the oceans, but there are clear warning signs that global biodiversity is collapsing under the weight of human activities.

Scientists estimate that more than 1 billion sea creatures, including birds, died during last summer’s extreme heat wave in the Pacific Northwest. The 2003 heat wave that killed about 70,000 people in Europe also extended over the Mediterranean Sea, where it triggered a series of mass die-offs of different ocean species, including rare corals. Recent global assessments suggest 40.7 percent of amphibians, 25.4 of mammals and 13.6 of birds are threatened with extinction.

Elsewhere around the planet, warming seas have driven many coral reef ecosystems to the point of functional extinction. Other signs of disruption include increasing jellyfish invasions and rapidly expanded Sargassum seaweed in the Caribbean. Hot water was also implicated in a mass die-off of starfish along the West Coast of North America, diminishing kelp forests and a federally designated “unusual mortality event” for gray whales lasting from 2019 into 2022.

“There is some evidence that extinctions have started ticking up already, but other human impacts are larger threats at the moment,” Pinsky said. But the new paper shows that global warming will soon overshadow other impacts like direct habitat degradation or pollution, he added. “What we do know is that extirpations, local extinctions already happen,” he said. “We do have evidence from a coral reef that even short periods of low oxygen can result in permanent displacement of a species from that reef.”

Sabine Mathesius, with the Potsdam Institute for Climate Impact Research, worked on a 2015 study showing that long-term plans to remove carbon dioxide from the atmosphere won’t do much to protect marine organisms from ocean acidification. By the time any large-scale atmospheric CO2 removal happens, some species sensitive to acidification could already be gone, she said. “I think there are many demonstrated impacts of warming and acidification, especially the impacts of warming,” she said. “There have been these huge coral bleaching events, so that’s reason for great concern.”

Bleaching occurs when ocean water temperatures become too warm and cause corals to expel the algae living in their tissues, turning their color white. But reducing emissions, rather than removing them from the atmosphere, can lower the possibility of a mass extinction, Deutsch said. “Species go extinct naturally all the time,” he said. “If we were to take that optimistic scenario and start reducing emissions now, it’s possible that we don’t really see a significant bump in extinction rates.”


An Interview with the Ocean, Transcript

From the Living On Earth, PRX, April 29, 2022

As we close out Poetry Month, we share the timeless poem “I Go Down to the Shore” read by the late Mary Oliver, and a sound rich performance of a creative piece it inspired. Author Kate Horowitz wrote “An Interview with the Ocean” and joined Living on Earth’s Aynsley O’Neill to bring it to the airwaves.

{ 5 comments… read them below or add one }

S. Tom Bond May 2, 2022 at 10:07 am

Bad stuff. No way to cool it. It is very expensive to put oxygen in and to take pollution out. The real problem with the world is the population has long since passed the earth’s healthy carrying capacity.

Tom Bond, Lewis County, WV


Pablo Neruda May 3, 2022 at 4:46 pm

Who shouted for joy at the birth of the color blue?

When I look once more at the sea, does the sea see me or not see me?

Why do waves ask me the same questions I ask them?

~ Pablo Neruda


Barbara Daniels May 3, 2022 at 6:00 pm

Regenerative Agriculture, where multi-species cover crops feed carbon-sequestering microorganisms, if done wide scale, is said to be able to put back into the soil enough carbon to more than compensate for all our carbon emissions world wide.

Please see for videos, newsletters and speakers.
The following YouTube video is interesting and information packed: “Best of Gabe Brown, Allan Savory, Joel Salatin and More”


Barbara Daniels May 3, 2022 at 6:28 pm

Carbon pricing is reported by the IPCC to be the fastest and most effective method to get Carbon emissions reduced.

But there is still legacy carbon that, by this late in the game, will keep the problem severe.

We must also draw carbon down into the soil with Regenerative Agriculture which mimics prairie ecosystems of wolves, grazers and mixed plant species.

Such No-till farming, without pesticides and synthetic fertilizers, and with intensive grazing, is essential to maintain the all-important microbial communities. These communities are destroyed by toxic chemicals and depend on active plant roots and heavy, but intermittent, grazing to thrive. Such methods also restore predatory and other beneficial life to the crop ecosystem, eliminating the need for pesticides in the first place.

Farmers are able to do this. It takes about three years to establish the system. This is where demonstration farms and subsidies for the transition are vital.


Eric Engle May 8, 2022 at 9:50 pm

Eric Engle, Parkersburg, May 5th from Facebook

I encourage everyone to think about life just a little bit differently today. The application of various sciences has taught us that we live in an approximately 13.9 billion year old universe, observably at least 93 billion light years across. Our only home in the cosmos, earth, is approximately 4.5 billion years old. Our anatomically modern selves have existed about 200,000 to 250,000 years and our brains have been about as complex as they are today for about 100,000 years. Plant and animal domestication gave us modern civilization over the last 10,000 to 11,000 years, following the last ice age, in a Goldilocks geologic epoch known as the Holocene. We Homo Sapiens have numbered about 117 billion and counting since we evolved.

Think about how amazing it is to be us. We’re made up of some of the same elements on the periodic table that everything we know to exist is also made up of. We don’t master or control nature or the cosmos, we ARE nature and the cosmos. We are, quite literally, the universe understanding itself. Let that give you a little joy today. Don’t be afraid of it or drive yourself mad at the complexity of it, just allow yourself to fully appreciate it. Let your 5 senses absorb the beauty, sound, fragrances, feels and even tastes of spring. Just exist for a little while.


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