What is the ocean basin

11 facts about our mysterious oceans

Have you ever wondered how long it would take to pump out the world's oceans? And where to put the water, where to store it? Less than 30 percent of the earth's surface is mainland - space would quickly become scarce.

The oceans store about 1,338,000,000 cubic kilometers of water, writes the US Institute for Cartography. Worldwide, the population is supplied with around 1,386,000,000 cubic kilometers of water. The oceans make up "96.5 percent of the water on earth," writes the institute. That's a lot of water - but why do we know so little about it?

So we have endless water?

Exactly. But because of the salinity, most of the oceans are unusable for us humans. There are desalination plants, but wherever we can, we use fresh fresh water from the rivers. However, the rivers only make up about a thousandth of one percent of the world's water supply.

How many oceans are there?

Here are our five oceans:

1st Pacific (168,723,000 square kilometers)

2. Atlantic (85,133.00 square kilometers)

3. Indian Ocean (70,560,000 square kilometers)

4. South Seas (21,960,000 square kilometers)

5. Arctic Ocean (15,558,000 square kilometers)

We often speak of the "seven seas". This designation is out of date and is not entirely correct. This is the number you get when you divide the Atlantic and Pacific into north and south halves.

Where is the deepest point?

The deepest point is in the Mariana Trench in the western Pacific. It is about 10,994 meters deep. One even suspects a depth of 11,034 meters. However, this is still unconfirmed. Researchers first came across the Mariana Trench when they lowered ropes with weights to the sea floor. Later, more accurate measurements were made with the help of ultrasound. As early as 1960, the researchers Don Walsh and Jacques Piccard dived down to 10,898 meters. In 2012, filmmaker James Cameron reached a depth of 10,898 meters on a solo dive. Still, to this day we don't know much about the trench.

Other deep-sea trenches - such as the Puerto Rico Trench - are located in the Atlantic, the Java Trench in the Indian Ocean and the Arctic Basin in the Arctic Ocean.

Which sea zones are there?

The oceans are divided into five layers: on the surface is the epipelagic zone. It runs along the continental shelf and is the warmest sea zone. Here the sunlight ensures that phytoplankton - the basis of the marine food chain - can thrive. Below that is enough Mesopelagic Zone up to 1000 meters. There is also the limit for the sun's rays. The die then begins in the dark bathypelagic zone, the reaches up to 4000 meters. With the abysopelagic zone begins the "abyss". It reaches up to 6,000 meters, where it meets the ocean basin and the continental foot. It then only goes deeper into the depths - or into the hadalpelagic zone.

Are the oceans moving?

Yes, but very slowly. We know waves, tides and currents - but there is more. The oceans move like on a global conveyor belt - also called thermohaline circulation: The ocean current moves in a constant cycle that exchanges deep water layers and surface water and thus also moves important nutrients. The so-called conveyor belt is created by differences in salinity and water temperature. It can take hundreds of years to complete a global circle.

Is the sea level changing?

Yes, but it takes time. Since 1900 the global sea level has risen 1.5 centimeters per decade. Satellite data show that sea levels have risen particularly rapidly since 1992 - by three centimeters within ten years. During the Ice Age around 2.5 million years ago, the sea level was significantly lower. At that time one could have traveled from Asia to North America via the Bering Strait. In the meantime she has gone underground. It is estimated that the sea level before the Ice Age - around three million years ago - was 50 meters higher than it is today.

Does the water temperature rise?

The U.S. Environmental Protection Agency has recorded a steady rise in surface temperatures since the 1880s. In between there were several records - for example in the 1940s - but also a few collapses. Today the oceans have the warmest temperatures in 130 years - a sign of climate change. Higher water temperatures can affect marine ecosystems. For example the habitats, migratory currents and the reproduction of plants, animals and microbes. Highly sensitive coral reefs, for example the Great Barrier Reef on the Australian east coast, suffer from this. Due to the increased water temperatures, the corals there continue to bleach.

Mountains under water - do they really exist?

Mount Everest is the highest mountain in the world. That's right - almost. Because the Manua Kea in Hawaii protrudes over 10,000 meters and is therefore the highest mountain on earth. About 4200 meters of the volcano are visible on the earth's surface.

  • Underwater wonder

    Unknown life

    Under hundreds of meters of ice in Antarctica, researchers accidentally discovered sessile animals (similar to sponges) adapted to extreme conditions - 260 kilometers from the open sea, darkness and freezing temperatures. What kind of creatures tied to the rock belong to, how and when they got to the remote place, what they feed on - that is still unclear.

  • Underwater wonder

    Water dragon

    It looks like a seahorse - but it's not! The red sea dragon is a rare marine fish. It was first described in 2015, but it is only now that researchers have been able to admire live specimens off the coast of Western Australia. The animals were observed eating at a depth of 50 meters.

  • Underwater wonder


    The "real" seahorses are also quite unusual. They are one of the few species that swim vertically. But since that doesn't work out really well, they are just bad swimmers. The males of the seahorses carry the fertilized eggs and give birth to the young.

  • Underwater wonder

    Electric eel

    The electric eel is not an eel at all, but a New World knife fish. But his gift makes his prey tremble: He generates electrical surges with voltages of up to 600 volts. He uses it to kill small fish, for example. Researchers have now found that its current organ also locates prey at the same time - similar to bats with their echo sounder.

  • Underwater wonder

    Archer fish

    The archerfish, related perch, lives in brackish water and has thought of another trick to kill its prey: it spits a jet of water into the air. Insects that are hit fall into the water - and the archer fish has lunch. Larger specimens of fish spit two to three meters.

  • Underwater wonder


    This fish is hiding in the sand, waiting for prey to swim past its head. Then he shoots up at lightning speed and enjoys his meal. Sky-gazers have large heads with large, upturned mouths. And first these giant eyes! Anyone who finds the species in nature should be careful: it is poisonous.

  • Underwater wonder


    Toxic and good at camouflage? The stonefish is an expert in both! It looks like a stone overgrown with algae - but if you step on it, you will feel its poisonous spikes. The poison is incredibly painful and can also kill people.

  • Underwater wonder

    Puffer fish

    Puffer fish have a kind of rubber stomach - they can fill it with a lot of water in a flash if they feel threatened. So they get bigger and spherical. But they also produce the poison tetrodotoxin; smallest amounts kill people quickly. In Japan, puffer fish are still a delicacy - if they are prepared by someone who knows how to do it.

  • Underwater wonder


    A frogfish lures prey with a kind of fishing rod: a fleshy outgrowth on the head called an illicium. It even lights up to arouse prey's curiosity. The victims approach and - bang - they land in the giant mouth of the predatory fish. Frogfish live almost everywhere in the world - even in the deep sea.

  • Underwater wonder

    Viper fish

    If you're looking for crazy-looking fish, you've come to the right place in the deep sea! High pressure, hardly any light and little to eat - animals have to adapt well to live here. Like the viper fish, which is up to 35 centimeters long. If prey does come by in the deep sea, he wants to make sure to get it - that's why he has such a large mouth and so many sharp teeth.

  • Underwater wonder


    Yes, flatfish are flat - no question about it. Clods are also extremely well camouflaged and bury themselves in the sediment. As a small plaice develops, one eye moves around the head to the other side so that both eyes are on one side of the fish.

  • Underwater wonder


    Mudskippers obviously couldn't decide whether to prefer water or land - and opted for both at the same time. They live on mangrove roots or - as the name suggests - in the mud. Their pectoral fins are unusually strong, so they can move across the country with them. They breathe through their skin like amphibians. But they are clearly fish.

  • Underwater wonder

    Hammerhead shark

    Who wouldn't call this head shape bizarre? Researchers believe that the flat head, stretched to one side, with two eyes at the end, gives hammerheads greater caution. So they see more.

    Author: Brigitte Osterath, Carla Bleiker

What lives in the ocean?

Sharks, turtles, fish (that we eat), deep sea fish (that we don't eat), giant squid, transparent shrimp, jellyfish, whales and dolphins ... and about three times as many unknown species.

And then it's over - are there no more living things on the sea floor?

Researchers have long been researching life forms in sedimentary layers between 860 and 1626 meters below the sea floor. There they found intact prokarya, i.e. microorganisms without cell nuclei. According to one study, such cells take around 1,000 to 3,000 years to renew - usually a matter of a few hours.

And what about some fun facts?

Of course there are still those too. For example, sharks like to bite into phone and power cables. Sperm whales can stay underwater for more than two hours. They dive more than 2000 meters into the depth. While the sperm whale has the largest head in the animal world, another whale colleague - the southern right whale - beats it for testicle size. Because they weigh a ton. Satisfied?