You probably know that the majority of our planet's surface is covered by bodies of water. (Specifically: It's a hair shy of 71%.) What you might not have heard, though, is that sea waves can move at hundreds of miles per hour. Or that the ocean's depths are home to millions of tons of gold. Or that scientists have more detailed, more extensive maps of Mars than they do of our own oceans. Yes, as deep as our planet's oceans are physically, they're deeper still when it comes to mystery and fascination. The following little-known facts about the ocean are sure to blow you out of the water.
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Thanks to the ocean, most of our planet is dark.
Oceans have an average depth of 12,100 feet, and because light waves can only penetrate 330 feet of water, everything below that point is dark. Seeing as water makes up most of the planet, this means that most of Earth exists in absolute darkness all the time.
The loudest ocean sound came from an icequake.
In 1997, the National Oceanic and Atmospheric Administration (NOAA) captured one of the loudest sounds ever recorded, which they named "The Bloop." The sound was loud enough to be picked up by sensors over 3,000 miles away. Originally, researches noted that the nature of the sound made it seem like it came from an animal, although no known animal exists that is large enough to make that sound. After 15 years, the NOAA concluded that the noise came from an icequake, which is when seismic activities cause a break in frozen ground. However, many people still question this conclusion, and The Bloop is the source of many conspiracy theories to this day.
The ocean's canyons make the Grand Canyon seem small.
Not to take anything away from the gorgeous Grand Canyon on Earth, but the Zhemchug Canyon, located in the Bering Sea, has a vertical relief of 8,520 feet—almost 2,500 feet deeper than the Grand Canyon.
The biggest ocean waves are beneath its surface.
The biggest ocean waves are not the ones that you can see from the shoreline. As physical oceanographer Kim Martini told Deep Sea News, the largest waves that occur in the ocean are called internal waves, which take place between two fluids with two different densities. As these internal waves travel—for thousands of miles, no less—they can grow to be 650 feet tall.
Water at the bottom of the ocean is incredibly hot.
In these deepest parts of the ocean, the water temperature may only be 2º to 4º Celsius, with the exception of water coming out of hydrothermal vents in the seafloor. The water released from these vents can be up to 400º Celsius (750º Fahrenheit). It's the intense pressure at these depths—the same pressure that would crush you—that keeps the water from boiling.
The ocean is home to nearly 95% of all life.
With so much going on well below the surface, it's easy to forget that the oceans are teeming with life. In fact, 94% of life is aquatic, according to the USA Science&Engineering Festival. That means those of us who live on land are part of a very, very small minority.
Coral produces its own sunscreen.
Too much sunlight can damage the algae that live inside coral in shallow water. To protect the algae, which are a main source of sustenance for the coral, the corals fluoresce. This creates proteins that act as a sort of sunscreen for the algae.
There's enough gold in the ocean for each of us to have nine pounds of it!
There's around 20 million tons of gold dispersed throughout the oceans. It is, however, diluted pretty much to a pulp—its concentration is only a few parts per trillion, according to the National Ocean Service. The ocean floor also has undissolved gold embedded in it, but it's not cost-effective to mine it. However, if the ocean's gold were equally distributed among every person on earth, we'd each receive nine pounds of it.
There's an ice sheet larger than the continental United States.
Just two vestiges of ice remain from our planet's last ice age: the Greenland Ice Sheet and the Antarctic Ice Sheet. The latter of the two is staggering in size. Clocking in at 5.4 million square miles, according to the National Snow&Ice Data Center (NSIDC), it's roughly the size of the continental United States and Mexico combined!
Sharks have their own underwater "café."
It turns out, humans aren't the only creatures in need of a winter vacation. In 2002, scientists discovered an area in a remote part of the Pacific Ocean, partway between Baja California and Hawaii, where typically coastal great white sharks will migrate to in the winter. The scientists named the spot the White Shark Café and some sharks hang around the area for months before heading back to the coast for warmer weather.
The planet's longest mountain range is underwater and is 10 times longer than the Andes.
The longest mountain range above water is the Andes, which is about 4,300 miles long. The actual longest mountain range on Earth, however, is the underwater Mid-Oceanic Ridge, which snakes between all continents and clocks in at around 40,390 miles long.
The Pacific Ocean is wider than the moon.
At its widest point, from Indonesia all the way to Colombia, the Pacific Ocean is wider than the moon, by quite a lot. This expanse of ocean is 12,300 miles across, which is more than five times the diameter of the moon!
One iceberg could supply a million people with drinking water for five years.
A large iceberg from Antarctica contains more than 20 billion gallons of water, which could conceivably supply one million people with drinking water for five years. But this piece of information isn't just a great way to illustrate how massive these icebergs are.
A company in the United Arab Emirates is actually planning to begin towing icebergs from Antarctica to the coast for exactly this reason. The country receives, on average, just four inches of rainfall each year, and is at risk of serious drought in the next 25 years, but may be able to solve the problem with this iceberg water solution.
Pressure at the bottom of the ocean would crush you like an ant.
In the Mariana Trench (35,802 feet below the surface), which includes the deepest point on the planet, the water pressure is eight tons per square inch. If you made your way down there, it'd feel like you were holding up nearly 50 jumbo jets.
The planet's biggest waterfall is in the ocean.
The tallest waterfall you're going to see on land is Angel Falls in Venezuela (above), which has a drop of over 3,200 feet. But that's nothing compared to the Denmark Strait Cataract, which is an underwater waterfall in between Greenland and Iceland formed by the temperature difference in the water on either side of the strait. When the cold water from the east hits the warmer water from the west, it flows underneath the warm water, with a drop of 11,500 feet. According to the National Ocean Service, the flow rate of the waterfall is more than 123 million cubic feet per second, which is 50,000 times that of Niagara Falls.
More people have been to the moon than to the Mariana Trench.
In human history, one dozen people have set foot on the moon, but just three people have managed to make it to the Mariana Trench because of the extreme conditions there. One of those people? Director James Cameron, who wrote about the dive for the magazine National Geographic.
Half of the United States exists below the ocean.
According to CBS News, more than half of the United States exists underwater. How, you ask? Simple! The borders of our country don't stop where the land ends; they expand 200 nautical miles away from shore.
Oceans have lakes and rivers too.
The ocean is like an entirely separate world. There are trenches, mountains, volcanos, and lakes and rivers. As seawater makes its way through layers of salt, it forms little depressions on the ocean floor. Because the water around these depressions contains more salt than normal seawater, it's denser and sinks into the depressions, creating little briny pools. These are a lot like the lakes we know in that they have shorelines—and some of them even have waves.
The Mediterranean used to be dry.
The Mediterranean used to be a dry basin until some five million years ago during the Zanclean flood—in which water from the Atlantic poured through the Strait of Gibraltar and filled the basin. Theories abound as to how this happened, but one catastrophic interpretation has the basin filling up in only two years, thanks to a massive torrent of water.
Sea ice is drinkable.
You can't drink sea water, but you can drink sea ice. However, you don't want to drink fresh sea ice, which still has little pockets of brine trapped in between ice crystals. As the ice ages, the brine drains out, and the ice becomes fresh enough that, according to the NSIDC, it can be melted and consumed.
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There's an internet connection in the ocean.
For the past few decades, according to Newsweek, submarine cables buried deep within the oceans have carried more than 99% of intercontinental data traffic—meaning that overseas communication is made possible by ocean-based cables.
Most of Earth's volcanic activity happens in the ocean.
When it comes to volcanic activity, the oceans have the most going on by a wide margin. In fact, 90% of all the volcanic activity on the planet happens in the ocean, and the largest known concentration of active volcanoes is in the South Pacific. It's an area no bigger than the size of New York, but it contains a whopping 1,133 volcanoes.
Tsunamis move at 500 miles per hour.
Tsunamis are triggered by seismic events and can, according to the Natural History Museum of Utah, move across the ocean at speeds of 500 miles per hour when the ocean depth is 3.7 miles. These waves are usually unnoticed, as they are only a few inches above the surface. And as the waves move towards land—and the depths shrink—they pick up water and increase in above-surface size (but, thankfully, slow down).
The United States lost a hydrogen bomb in the ocean.
Every year, shipping containers get lost in the ocean, and oil spills are unfortunately common. But in 1966, the United States managed to lose a hydrogen bomb at sea. Luckily, according to History, it was eventually found with the help of a Spanish fisherman.
The world's largest living structure is in the ocean.
The world's largest living structure isn't an enormous copse of trees or even a massive fungus—it's the Great Barrier Reef off the coast of Australia. The reef spreads out over an area of 133,000 square miles and is so huge it can actually be seen from outer space.
There are three million shipwrecks in the ocean.
From the Titanic to Christopher Columbus's Santa Maria, the oceans are home to around three million shipwrecks, according to the United Nations Educational, Scientific and Cultural Organization.
The ocean has more artifacts than all the world's museums combined.
Thanks to these millions of shipwrecks, the ocean houses countless treasures and artifacts. National Geographic estimates that there are more treasures on the bottom of the ocean than in all the world's museums combined.
If all the ice melted, the sea level would rise 26 stories.
According to the NASA's Jet Propulsion Laboratory, if all of the glaciers and sheets of Arctic sea ice melted at the same time, the sea level would rise an estimated 262 feet, which is about the height of a 26-story building—just a bit shorter than the Statue of Liberty.
The ocean is a magnet for heat.
"The ocean is the largest solar energy collector on earth," according to NOAA. The proliferation of greenhouse gases prevents heat from escaping our planet's atmosphere, and all that energy has to go somewhere—unfortunately, it goes straight into the oceans. As a result, ocean temperatures have rapidly risen over the past few decades.
The ocean is our greatest source of oxygen.
Most of the oxygen in our atmosphere comes from tiny marine plants in the ocean—specifically, phytoplankton, kelp, and algal plankton. Scientists estimate they're responsible for around 70% of the atmosphere's oxygen, according to National Geographic.
We have better maps of Mars than of the ocean.
Less than 5% of the ocean has been explored, according to the National Ocean Service. In fact, we have better maps of Mars than of the oceans, despite the fact that it's nearly 50 million miles away.
More than 90% of the planet's lifeforms are undiscovered and underwater.
Because precious little of the oceans has been explored, it is currently estimated that 91% of the species that exist under the sea have yet to be discovered, according to a 2011 study published in PLoS Biology.
Nearly 100% of Earth's living space is in the ocean.
The oceans make up almost all of the living space on Earth. This makes the world's oceans the largest spaces in the known universe inhabited by living organisms.
The part of the ocean that's the furthest from land is named after a classic novel.
Found in the Pacific Ocean, Point Nemo is the most remote spot in another of the world's oceans. According to the NOAA, it's about 1,670 miles from land. And it's aptly named after a character in Jules Verne's famous book, Twenty Thousand Leagues Under the Sea.
The proteins that help arctic fish live in super-cold temperatures may change how our food is store.
As biologist Peter Davies explained to NPR in 2013, organisms that live in the waters at each pole have antifreeze proteins in their bodies that keep ice crystals from forming on them and harming them. Scientists are trying to figure out how these proteins can be applied to more human problems, like keeping your pint of Cherry Garcia from getting freezer burned.
The ocean's rip currents are the biggest danger you face at the beach.
Per the NOAA, rip currents, which are currents that occur near breaking waves, "account for more than 80% of rescues performed by surf beach lifeguards." What can you do to stay safe from them? Firstly, never swim at a beach without a lifeguard present and secondly, if you do get caught in a current, don't fight against it. Let it carry you until you can safely swim back to shore.
Climate change impacting the Atlantic could put Northern Europe in a "deep freeze."
One of the many effects of climate change is that the thermohaline circulation of the Atlantic Ocean—the system that balances the ocean by keeping warm and cool currents moving in the right direction—is slowing down. According to Smithsonian magazine, if the current stops getting enough warm water to Europe, part of the continent could see a massive drop in temperature.
By 2050, the plastic in the ocean will outweigh the fish.
In addition to climate change, pollution is also rapidly changing our world's oceans. Conservation International says that humanity dumps eight million metric tons of plastic into them every year. That means that, in a little less than 30 years, there will be more tons of plastic in the ocean than there are fish.