The oceans provide the “fuel” for almost all the thunderstorms on Earth: water that evaporates from the ocean surface. But the oceans generally don’t provide the “trigger” for the big storms. As one indication of the difference, about 90 percent of all lightning happens over land.

A thunderstorm forms when warm, humid air rises high into the atmosphere and condenses to make clouds. The humidity comes from the oceans. Storms in the Great Plains, for example, are fed by water vapor from the Gulf of Mexico. And the summer monsoon in the Southwest is fed by the Gulf of California.

But the storms need a strong source of heat to get the water vapor to rise high enough to form clouds. During the warm portion of the year, the land gets hotter than the oceans. There’s also a bigger contrast on land—some areas heat up more quickly, so they’re more likely to start building the clouds. Terrain also plays an important role—mountains can push air upward. In contrast, the oceans are more stable, so there’s not much to trigger big storms.

Oceans do outperform the land in one way, though—they produce more “superbolts” of lightning. Such bolts can be a thousand times more powerful than a typical discharge. That appears to be because the salt content makes ocean water a better conductor of electricity than soil or fresh water. So when a thunderstorm does form over the ocean, it’s much more likely to produce a really spectacular light show.

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At the time of the dinosaurs, the oceans were filled with lots of big, scary creatures. The biggest and scariest might have been some king-sized ancestors of the modern octopus. Some recent research says these monsters could have been as long as a big-rig truck. And they would have been smart—critters you wouldn’t want to see in the flesh.

Scientists looked at the fossilized jawbones of 15 specimens that were already known. And they used a sophisticated imaging technique plus AI to scan a dozen others that hadn’t been recognized as octopus relatives. All of the fossils were found in Japan or on Canada’s Pacific coast. The octopuses lived between 72 million and 100 million years ago.

To determine the size of the creatures, the scientists compared the jawbones to those of modern octopuses. They found that the old guys comprised two species. The largest of them could have reached more than 60 feet long.

The scientists also found that most of the jawbones were chipped and eroded—they’d lost up to a tenth of their original volume. That means the creatures used their jaws to crack the shells and bones of lots of smaller prey.

Many of the jaws were eroded more on one side than the other. That suggests the octopuses preferred to use one side of their body more than the other—just as people prefer one hand over the other. That’s considered a sign of intelligence. So these smart, giant creatures could have been the top ocean predators in the age of the dinosaurs.

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Big ships can really stir things up—especially in shallow coastal waters. A ship’s wake can extend far below the vessel. It creates turbulence that mixes up the water. It can even extend into the sediments on the sea floor. And that can release a lot of methane—a gas that’s much more efficient than carbon dioxide at warming the atmosphere.

Researchers discovered the connection between ships and methane releases more than a decade ago. They were studying shipping in Neva Bay, a shallow extension of the Baltic Sea on the northwestern coast of Russia. It’s home to Saint Petersburg, which has a busy port.

The researchers found that many ships cruising in the bay produced two bursts of methane. One came from the ship itself—from burning fossil fuels. The other came later, and wasn’t produced by the engines.

Scientists recently took another look at the observations. And they combined them with models of how a ship’s wake churns the water, and how bubbles of methane in the sediments make their way into the air.

They concluded that the wakes were stirring up the sediments. That released bubbles of methane, which floated to the surface, then into the air. There was a 20-fold increase in the amount of methane above the shipping lanes compared to the surrounding area.

Many of the world’s largest ports are built along similar coastal environments. So the churning action of passing ships could add more methane to the air every year.

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Some coastal areas along the Caribbean Sea and the Gulf of Mexico have had a big, stinky problem over the past decade or so. Big mats of seaweed have been washing ashore. It can harm other marine life, while making the beaches unpleasant.

The seaweed is called sargassum. In the open ocean it provides habitat, shelter, and hunting grounds for fish, sea turtles, and other creatures.

It’s been concentrated in the Sargasso Sea—a wide area that extends from the southeastern coast of the United States into the Atlantic Ocean. But over the past decade, the amount of sargassum in that region has dropped dramatically. That might be a result of changes in the Gulf, where annual blooms of the seaweed begin. At the same time, a new region started to develop—the Great Atlantic Sargassum Belt, populated by a different species of sargassum.

The belt stretches from West Africa to Brazil and into the Caribbean. It’s grown larger and denser over the years. It might be fed by nutrients from the Amazon River and other sources. Or it might be fed by changes in circulation patterns in the Atlantic, which dredge more nutrients from the deep ocean.

As the sargassum reaches shore, it can choke seagrass beds and reef systems. As it decays, it produces a gas that smells like rotten eggs. And it can contain high levels of arsenic and other nasty compounds. So the new area of sargassum is providing great habitat in the open ocean, but a headache for many coastal regions.

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It’s hard to think of anything good coming from earthquakes. But for life in part of the Southern Ocean, they could be crucial. A recent study found that underwater quakes could intensify “blooms” of phytoplankton.

These tiny plant-like organisms form the base of the marine food web. They also absorb carbon dioxide from the air, and release oxygen. So anything that bumps up their numbers a bit is good for life in the Southern Ocean and around the planet.

Every spring and summer, a big bloom develops between Antarctica and New Zealand and Australia. But three decades of satellite photos revealed a huge range in the size of the bloom. Some years, it covers an area the size of Delaware. In others, it can be dozens of times larger—as big as California.

The blooms are fed by iron—a key nutrient. But there’s not a lot of it in the Southern Ocean. And the location of the annual bloom isn’t near any of the most common sources of iron. So researchers looked for a “deeper” cause.

They found that the bloom occurs in a region with lots of underwater volcanoes. “Vents” pump hot, iron-rich fluids into the water—possibly feeding the bloom.

Records of volcanic activity in the region showed that, when the ocean floor was rocked by earthquakes of magnitude five or greater in the months before a bloom, the event was much bigger. The tremors might clear out blocked vents, or create new ones, boosting the amount of iron in the water—a positive impact for earthquakes.

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Most parents wouldn’t be pleased if you told them that their baby looks nothing like them. But some fish parents might be happy at such a description. The lack of resemblance could make it more likely that their offspring will reach adulthood.

The newborns of many fish, squid, and other species look nothing like the adults. These larvae have big fin extensions, transparent bodies, long tendrils, and other odd features. Some of these features make them slower and less maneuverable, so it’s harder for them to get away from predators. And some make them easier to see.

But the odd appearance may provide a big advantage: The larvae may be “mimicking” jellyfish or other creatures that are either dangerous or just not worth the effort to catch. So predators leave them alone.

A recent study supports that conclusion. Biologists looked at thousands of pictures snapped by divers at night, mainly from a site near Palm Beach, Florida. The images allowed the scientists to see the larvae alive and in their natural environment. Before that, biologists had been limited to seeing mainly colorless, damaged specimens that had been collected in nets and preserved in jars.

The pictures showed the larvae of many species of fish and other creatures mingling with jellyfish and other less-desirable critters. And there was a striking overall resemblance between the larvae and the noxious animals. So the larvae could be hiding in plain sight—saved by the lack of a family resemblance.

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In August of 2024, a fisherman in Costa Rica pulled in a fish that looked like a refugee from a “Finding Nemo” sequel—a shark the color of a Creamsicle with white eyes. The fisherman released it back into the Caribbean. But marine biologists studied pictures of it. And they concluded that the shark had a combination of two rare conditions.

The fish was a nurse shark—a common species in the Caribbean, the Gulf of Mexico, and elsewhere. It’s a low-key species that has a rounded snout that looks a little like a catfish.

Most adults are gray-brown or yellow-brown on top, with a lighter colored belly. But the one caught in Costa Rica was bright tangerine. Its eyes were all white, including the pupil—no scary shark-like stare. There’s no record of that color combo among nurse sharks anywhere. And there’s no record of any shark species with it in Caribbean waters.

Researchers said the shark most likely had two genetic disorders—albinism and xanthism. Albinism accounts for the white eyes. Xanthism accounts for the skin color—it boosts the level of yellow pigments.

Sharks and other fish use their color to hide from predators and prey. So you might think that a tangerine-colored shark would have a tough time surviving. But the Costa Rican shark was about six and a half feet long—only a bit less than the size of a typical adult. So it’s managed to get along just fine—a tangerine shark sliding through the clear blue waters of the Caribbean.

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It’s hard to think of a Category-5 hurricane as a good thing. But in 2025, Hurricane Humberto helped save the East Coast from a direct hit by a smaller hurricane, Imelda.

The deflection was an example of the Fujiwhara effect. It’s named for the Japanese scientist who first described the effect, in 1921. It’s an interaction between two or more storms that pass close together. It applies to both tropical and non-tropical cyclones.

Such storms are big and powerful. But they’re influenced by the conditions around them. And the stronger the influence, the more the storms can change.

As two storms approach each other, they can change direction, for example. They might move closer, with both of them spinning around a point between them. If there’s a big difference in the sizes of the storms, the bigger one might deflect the smaller one, or even absorb it. But if they’re about the same size, they might loop around each other, then be shot out in opposite directions.

Tropical storms and hurricanes begin to interact at separations of about 900 miles. As they get closer, they may spin faster. And at less than 200 miles, they’re likely to merge. The exact process depends on the size and intensity of the storms and many other factors, so it’s tough to forecast.

The Fujiwhara effect is seen more often in the Pacific Ocean. But it does play out in the Atlantic as well. The Humberto-Imelda interaction is the most recent—a dance of giant storms that helped coastal residents—this time.

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The saltwater crocodile really gets around. It’s found throughout the Indian and western Pacific oceans. That makes it one of the most cosmopolitan reptiles on the planet.

But it’s not quite as widely spread as it once was. Crocodiles that once inhabited the Seychelles islands were members of the same family. But they were exterminated by early settlers.

The saltwater croc is the largest reptile on Earth. Adult males can reach 20 feet or longer and weigh more than a ton. They’re super-aggressive—they’ll eat anything they can catch, and they can catch almost anything—including people.

When people first settled on the islands, in 1770, they found plenty of crocs. Within half a century, though, the settlers had wiped them out. That made the islanders safer. But it left modern-day science with a question: Were the crocodiles members of the saltwater family, or were they a separate species? With no living examples, the question has been hard to answer.

In a recent study, though, scientists were able to extract DNA from parts of crocodiles preserved in museums. They compared the samples to those of modern saltwater crocs. And the samples matched—the Seychelles monsters were relatives of the crocodiles found across the region.

The Seychelles are a long way from any major land mass—about 900 miles from Africa, and 1700 miles from India. So the crocs had to travel a long way to reach them—expanding the range of this cosmopolitan reptile.

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Most of the time, life in the oceans works in one direction: the big guys eat the little guys. That passes nutrients up the food web. But sometimes, the little guys may turn the tables. Egged on by annual spawnings, they may poach the eggs of larger species. That passes nutrients down the food web. Of course, the big guys then gobble up some of the egg eaters, scrambling things up.

Eggs are rich in essential fatty acids — compounds that are needed for normal development and body function. Eggs can supply a lot of the fatty acids in the animals that eat them.

Researchers at the University of Texas Marine Science Institute suspected that smaller organisms were feeding on the eggs of larger species. They tested that idea in 2020 and ’21, around the annual spawning of red drum, a game fish on the Texas coast. A single female releases millions of eggs, so the coastal waters around Port Aransas are filled with them in the fall.

The scientists collected several types of animals before, during, and after the fall spawning. They then tested the tissues of those organisms in the lab. The fatty acids in red-drum eggs have a unique chemical “fingerprint,” so the tests revealed which subjects had eaten the eggs. During and after the spawning season, high levels of those markers were seen in jellyfish and jellyfish-like organisms, as well as one small species of fish.

The study confirmed that these organisms can scramble things up—turning the tables on the big guys.

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