John Abraham, professor of thermal sciences at the University of St. Thomas School of Engineering, is featured in national and international coverage examining record ocean warming, with news outlets citing his research on ocean heat content as a key indicator of climate change. Abraham’s work shows that the world’s oceans have absorbed unprecedented amounts of heat for a ninth consecutive year, a trend scientists say is driving more intense weather, rising sea levels and widespread impacts on marine and coastal systems.
From The Guardian:
... The atmosphere is a smaller store of heat and more affected by natural climate variations such as the El Niño-La Niña cycle. The average surface air temperature in 2025 is expected to approximately tie with 2023 as the second-hottest year since records began in 1850, with 2024 being the hottest. Last year the planet moved into the cooler La Niña phase of the Pacific Ocean cycle.
“Each year the planet is warming – setting a new record has become a broken record,” said Prof John Abraham at the University of St Thomas in Minnesota, US, and part of the team that produced the new data.
“Global warming is ocean warming,” he said. “If you want to know how much the Earth has warmed or how fast we will warm into the future, the answer is in the oceans.”
From WIRED:
John Abraham, a professor of thermal science at the University of St. Thomas and one of the authors on the paper, says that he sometimes has trouble putting this number into contexts laypeople understand. Abraham offers up a couple options. His favorite is comparing the energy stored in the ocean to the energy of atomic bombs: The 2025 warming, he says, is the energetic equivalent to 12 Hiroshima bombs exploding in the ocean. (Some other calculations he’s done include equating this number to the energy it would take to boil 2 billion Olympic swimming pools, or more than 200 times the electrical use of everyone on the planet.)
“Last year was a bonkers, crazy warming year – that’s the technical term,” Abraham joked to me. “The peer-reviewed scientific term is ‘bonkers’.”
The world’s oceans are its largest heat sink, absorbing more than 90 percent of the excess warming that is trapped in the atmosphere. While some of the excess heat warms the ocean’s surface, it also slowly travels further down into deeper parts of the ocean, aided by circulation and currents.
From Inside Climate News:
... While warming of the top 500 meters of oceans was visible as early as the late 1970s, man-made heat now penetrates as deep as 2,000 meters below the surface. According to Trenberth, it takes roughly 25 years for heat to travel to such depths, creating a warming effect that will likely persist for centuries. Though the mean sea-surface temperature was lower than in 2023 and 2024, it remained the third warmest year on record.
“A warming ocean leads to warmer, wetter air – which, in turn, leads to stronger storms,” said John Abraham, a professor of thermal sciences at the University of St. Thomas in Minnesota. As ocean temperatures increase, so too does evaporation, leading to more moisture in the atmosphere. “Think of ‘weather on steroids.’ We can expect our weather to become more extreme and unpredictable.”
From WCCO Radio:
Adam Carter: What is happening to our climate and the work you are doing, especially this latest research that was just released. You do this every year, right. Can you explain what was released today.
John Abraham: Think of it as an annual checkup. Every year my research team, which is an international group of about 50 researchers, takes the pulse of the planet. We take the temperature of the planet and determine what happened with climate change in the previous year.
This is the eighth year in a row we have done this study, and every single year we have broken the record. This past year was particularly surprising. I will use an analogy to explain it.
The amount of heat that went into the ocean last year was 23 zettajoules.
Carter: Right. I am guessing most listeners think you just made that up. Maybe a tiny fraction know what a zettajoule is. That is a one with 21 zeros after it. It is a huge number.
Abraham: Exactly. Because the number is so large, we need analogies. The one that hits home most for me involves Hiroshima bombs. I know that is uncomfortable to think about, but consider the energy released by one atomic bomb.
Now imagine 12 of those detonating every second of every day, all year long. Twelve Hiroshima bombs every second. That is how much heat is going into the oceans.
It is almost impossible to comprehend. Another way to think about it is this. If you add up all the electrical energy used by everyone on the planet, the heat going into the ocean is more than 200 times that amount.
Carter: Those numbers are mind-boggling.
From China Daily:
The Earth’s oceans are heating up, and that is a problem for all of us. Fortunately, it is a problem we can fix. ...
Why are we studying the oceans? It is because the oceans are very large. They cover 70 percent of the planet. They are also very deep, on average thousands of meters, and therefore have a tremendous mass. This also means that ocean temperatures change slowly over time, making them an excellent way to measure long-term climate change. An important feature of the oceans is that they absorb approximately 90 percent of the extra heat from global warming. Therefore, if you want to measure how fast the Earth is warming, the answer is in the oceans.
Oceans are also important because they greatly affect weather patterns. As air passes over the ocean, it picks up heat and moisture – the two ingredients that drive weather. So, as our oceans warm, the atmosphere warms and becomes more humid – leading to more extreme weather.
From Daily KOS:
Even as scientific knowledge advances and sharpens, one conclusion has remained steady: the largest unknown in the climate system is human behavior. The future still depends on whether societies reduce emissions, prepare for unavoidable impacts, and act together. If they do, a livable climate — one that can sustain both human communities and ecosystems — remains within reach. Meanwhile, however, the perils keep staring us in the face and the response is … inadequate.
The world’s oceans are heating in a way that feels less warning than verdict, absorbing the overwhelming majority of the damage inflicted by an economic system that treats the atmosphere as a free sewer and the sea as an infinite sponge. ...
“Global warming is ocean warming,” said Prof. John Abraham, a member of the study team at the University of St. Thomas in Minnesota. “Each year the planet is warming — setting a new record has become a broken record. If you want to know how much the Earth has warmed or how fast we will warm into the future, the answer is in the oceans.”
Although the planet moved in 2025 into the cooler La Niña phase of the Pacific Ocean’s El Niño-La Niña, cycle, the upper 2,000 meters (1.2 miles) of the global ocean absorbed 23 zettajoules of heat last year — an amount of energy equivalent to more than 200 times the world’s annual electricity use...
From Minnesota Public Radio:
Huttner: Let us talk about the big picture. What are the headlines on ocean temperatures in 2025?
Abraham: This research, published by an international team of scientists, shows unequivocally that Earth’s oceans are warming. And that really matters for a couple of reasons.
First, about 90 percent of the heat from global warming ends up in the oceans. So if you want to know how much global warming we have experienced, the answer is in the oceans. They tell us how much warming has already occurred and give us insight into how much warming we may see in the future.
Huttner: Remind us how important the oceans are as a kind of heat sponge, and how they can give that energy back to the atmosphere.
Abraham: The oceans are enormous. Everyone has heard the saying that a watched pot never boils, and that is actually true. It takes a lot of heat to raise the temperature of water, even on your stove. Now imagine applying that idea to the entire planet.
As the oceans warm, air passing over them picks up heat and moisture. That heat and moisture, or humidity, drives weather patterns and fuels storms. As oceans warm, they give more heat and more humidity to the atmosphere. That is what is supercharging our weather and making it wild and extreme, not only in the United States, but around the world.
Huttner: We have seen research showing that stronger and wetter storms, including hurricanes, are linked to warmer oceans. How do warmer oceans affect us here in Minnesota?
Abraham: The rain and snow that fall in Minnesota began over the ocean. Much of it actually starts over the Pacific Ocean. When heat and moisture enter the atmosphere, they are carried long distances. So all of the weather your listeners experience, no matter where they live, is influenced by the oceans.
From FOX 9:
Maxx Fuller: We know generally what climate change is, but what are some of the factors contributing to ocean warming specifically?
John Abraham: Climate change is the main factor, caused by heat trapping gases we release into the atmosphere. That part is not new. My team has been studying the oceans, and this is the eighth year in a row we have broken a heat record.
But there are other things happening too. The ocean does not warm evenly. If you cast a fishing rod off the coast of Japan, you are in much warmer water than off the coast of Chile. Some areas are warming very fast, others more slowly.
The region from Japan to Canada is warming rapidly. The northern and southern Atlantic are warming fast, and the Mediterranean is warming quickly as well. Some parts of the ocean heat up much more slowly, and that is an important scientific question. If we can understand why warming is slower in some regions, maybe we can apply that knowledge elsewhere.
Fuller: What can be done about this? Should we be trying to slow it down, and what is the ultimate goal?
Abraham: I am a pragmatic person. We should absolutely try to slow climate change, but we should do it in a way that does not cripple the economy. I believe we can reduce this problem without harming our pocketbooks. ...
