Record Ocean Heat Frightens Scientists, Threatens Grim New Era


For the last few decades, Earth’s oceans have been absorbing the vast majority of global warming – over 90%. This has resulted in declining oxygen levels, marine heatwaves, and a myriad of problems for marine life. Last March, I covered research from Monterey Bay Aquarium that confirmed that “extreme” heat is now the norm for a majority of the ocean’s surface. That would be alarming enough, even though the news is a year old, but now we’ve got more bad news to add to it:

Temperatures in the world’s oceans have broken fresh records, testing new highs for more than a month in an “unprecedented” run that has led to scientists stating the Earth has reached “uncharted territory” in the climate crisis.

The rapid acceleration of ocean temperatures in the last month is an anomaly that scientists have yet to explain. Data collated by the US National Oceanic and Atmospheric Administration (NOAA), known as the Optimum Interpolation Sea Surface Temperature (OISST) series, gathered by satellites and buoys, has shown temperatures higher than in any previous year, in a series stretching back to 1981, continuously over the past 42 days.

The world is thought to be on the brink of an El Niño weather event this year – a cyclical weather system in the Pacific, that has a warming impact globally. But the El Niño system is yet to develop, so this oscillation cannot explain the recent rapid heating, at a time of year when ocean temperatures are normally declining from their annual March and April peaks.

Prof Mike Meredith of the British Antarctic Survey said: “This has got scientists scratching their heads. The fact that it is warming as much as it has been is a real surprise, and very concerning. It could be a short-lived extreme high, or it could be the start of something much more serious.”

The image shows the annual variation of ocean surface temperatures for every year from the present, dating back to 1981. April 2023 is far and away the hottest global sea surface temperature from that time period.

The image shows the annual variation of ocean surface temperatures for every year from the present, dating back to 1981. April 2023 is far and away the hottest global sea surface temperature from that time period.

That “something much more serious” is will happen, sooner or later. As the oceans warm, their capacity to keep absorbing the excess heat diminishes, which means that from our perspective, things are going to suddenly start warming a lot faster. Hotter oceans also have less capacity to absorb gases from the atmosphere, which increases the rate at which greenhouse gas concentrations increase. On top of all of that, there’s the fact that a hotter ocean creates stronger storms, which will set us even further back in this age of endless recovery. If the oceans are reaching some sort of thermal tipping point, that could also disrupt the big ocean currents that are so important to moving heat around the planet, and to bringing oxygen to the depths. A big change to those currents could have pretty immediate and dramatic effects on a global scale. It’s not just this year, either. Over the last 15 years, the oceans have apparently warmed as much as the previous 45 years; a finding that has been described as so disturbing that scientists don’t like to talk about it:

Scientists from institutions including Mercator Ocean International in France, Scripps Institution of Oceanography in the United States, and Royal Netherlands Institute for Sea Research collaborated to discover that as the planet has accumulated as much heat in the past 15 years as it did in the previous 45 years, the majority of the excess heat has been absorbed by the oceans.

In March, researchers examining the ocean off the east coast of North America found that the water’s surface was 13.8°C, or 14.8°F, hotter than the average temperature between 1981 and 2011.

The study notes that a rapid drop in shipping-related pollution could be behind some of the most recent warming, since fuel regulations introduced in 2020 by the International Maritime Organization reduced the heat-reflecting aerosol particles in the atmosphere and caused the ocean to absorb more energy.

But that doesn’t account for the average global ocean surface temperature rising by 0.9°C from preindustrial levels, with 0.6°C taking place in the last four decades.

The study represents “one of those ‘sit up and read very carefully’ moments,” said former BBC science editor David Shukman.

Lead study author Karina Von Schuckmann of Mercator Ocean International told the BBC that “it’s not yet well established, why such a rapid change, and such a huge change is happening.”

“We have doubled the heat in the climate system the last 15 years, I don’t want to say this is climate change, or natural variability or a mixture of both, we don’t know yet,” she said. “But we do see this change.”

It’s true, we don’t know for sure what’s going on. Maybe Godzilla is to blame!

In all seriousness, I don’t blame Shuckmann for being careful in the claims she makes. If I’m annoyed, it’s because of the people who love to jump on qualifiers like that to say, “See? They don’t even know what’s happening!” The reality is that even if this turns out to be a blip, and we’re lucky enough to get cooler sea surface temperatures over the next few years, that won’t change the trajectory we’re on. The heat in the oceans won’t just go away, even if it’s not at the surface. What’s more, when you have an unusually hot year, that adds to the momentum of the whole crisis. Ice melts a bit faster, permafrost thaws and rots a bit more, we get a few more fires, and now there’s just that much more CO2 in the atmosphere, and that much less ice to reflect sunlight back into space, and ecosystems are just that much less resilient.

As long as greenhouse gas levels keep rising, this can only go one way.

A study published earlier this year also found that rising ocean temperatures combined with high levels of salinity lead to the “stratification” of the oceans, and in turn, a loss of oxygen in the water.

“Deoxygenation itself is a nightmare for not only marine life and ecosystems but also for humans and our terrestrial ecosystems,” researchers from the Chinese Academy of Sciences, the National Center for Atmospheric Research, and the National Oceanic and Atmospheric Administration said in January. “Reducing oceanic diversity and displacing important species can wreak havoc on fishing-dependent communities and their economies, and this can have a ripple effect on the way most people are able to interact with their environment.”

The unusual warming trend over recent years has been detected as a strong El Niño Southern Oscillation (ENSO) is expected to form in the coming months—a naturally occurring phenomenon that warms oceans and will reverse the cooling impact of La Niña, which has been in effect for the past three years.

“If a new El Niño comes on top of it, we will probably have additional global warming of 0.2-0.25°C,” Dr. Josef Ludescher of the Potsdam Institute for Climate Research told the BBC.

It looks like we should expect more extreme weather in the coming year or so, but if we have reached a point where the oceans are going to be less effective at absorbing heat and greenhouse gases, then things up on dry land are probably going to start progressing much more quickly. I often talk about how the action that has been taken so far to end fossil fuel use is criminally inadequate, but at this point that’s only half the picture. It’s been a decade or two since we passed the point at which dangerous warming could still be prevented. The inaction of our leadership, which seems to be a gerontocracy still stuck in the mid-20th century, has meant that it will keep warming for the rest of my life, and the rest of your life, dear reader, and the lives of your children, and of their children. Absent a series of technological and political miracles that seems very unlikely, this is our future now.

That means that simply ending fossil fuel use, while absolutely essential, is not enough. We must do better to prepare for a hotter planet. We must change how we produce food, to protect it from the conditions that we have created. We must reshape our infrastructure to deal with higher temperatures, stronger storms, and rising seas. We must take measures to to help those countries that have been deliberately kept poor for the benefit of rich nations withstand the hellish forces that have been unleashed upon this world.

Well, we must do all of that if we value human life. If we want to weather this storm, and keep making the world better.

It is past time that we considered that “we” don’t really want any of that, when it comes to the aristocracy of global capitalism. Despite Biden’s words, his actions show that he feels no urgency to deal with climate change. I’ll probably write more about this soon, but the people who run our world seem to be deliberately driving us to destruction, while setting themselves up to rule what remains. Maybe they think that reducing the population will reset the timer on how long they can cling to a system based on endless growth. Whether it’s delusion, malice, or both, they seem poised to use global warming to kill off most of humanity, while they live in luxury and insist that it’s all for the greater good.

I think the oceans could literally be boiling, and they’d still insist that they know best.

We are running out of time and options, both as a species, and as the working class that makes up most of that species. I don’t know how much longer we can afford to wait for those at the top to go against everything they believe, and act for the benefit of humanity. I think we’ve already wasted more time than we had on that false hope, and we’ve yet to fully grasp the price that we’re going to pay for that. We need revolutionary change, and we need it as soon as possible. It is my hope that a combination of worsening conditions, and a general strike, might get the powerful to change their tune. I don’t know how to get there from where we are. I’ll look into it, but I feel like we need more than my current attempt at an organizing guide. Mass unionization is probably the most direct route to the kind of organization we need. It’s a concept that’s familiar to people, and unions are more popular now than at any time I can remember. While I still like the notion of organizing centered around communities, the reality is that work is a bigger part of people’s lives than community right now, so it makes sense on multiple levels to start there.

In the meantime, one thing that individuals can do, outside of organizing and agitating, is prepare for hard times. If you can afford to, make a habit of keeping a store of non-perishable food, not just because climate change may disrupt supply chains and lead to shortages, but also because in the event of a general strike, you and those around you are likely to need the supplies. I’m pretty sure I’ve said this before, but a strike is a siege, and so success will depend on how well supplied we are.

At the same time, if you can, feed people who are hungry. Help people who need help. Economic desperation is the main weapon wielded by the rich in the class war, and undermining that empowers people, and builds solidarity. Those of us who want humanity to have a future have to come together and fight for that future. What I laid out above is the only path I can see that might lead to revolutionary change without war. As mentioned above, this big jump in ocean temperatures may just be a blip. We might have a rough year, then go back to a “normal” that’s still unacceptable. But we might not. Things have gone so far that it’s a real possibility that we’ve passed a major tipping point sooner than expected. If we don’t organize, prepare, and change course very soon, things will get ugly.


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