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The North Sea

The North Sea

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How deep is the North Sea on average?

The North Sea

This is the northeastern part of the Atlantic ocean, the North Sea. It is bordered by the British Isles from the southwest to the northwest, by Norway to the northeast, Denmark to the East, Germany and the Netherlands to the southeast, and Belgium and France to the south. To a large extent, the North Sea was formed by slowly moving masses of ice — glaciers. In the north, the shore is marked by steep cliffs and deep fjords, while in the south, you can find sandy beaches, and coastal wetlands. Its location on the continental shelf makes the North Sea rather shallow — on average only about 90 metres deep.

The Sea’s deepest part, the Norwegian trench, runs parallel to the Norwegian shoreline. It stretches about 20 to 30 kilometers wide, and is 725 metres deep. The North Sea receives freshwater from a number of rivers from continental Europe and surrounding islands. The Elbe and Rhine are some of the biggest rivers. Water in the North Sea is constantly mixed by currents and tides, which bring in a rich supply of nutrients.

These nutrients are important for survival of tiny microorganisms called plankton, which form the base of most food chains in the sea. The abundance of plankton means many types of fish live here, including cod, haddock, mackerel and herring. There are different species of seals, dolphins and whales in the North Sea too. The shores bordering the North Sea are also part of its ecosystem, and are home to many different species of seabirds, among them the herring gull and the atlantic puffin. Some birds stay year round, while others simply pass through the region on their migrations.

The North Sea has a number of areas where brown algae — kelp, grows. These kelp forests provide food, breeding grounds and refuge for many different organisms, such as fish, sea mammals and even sea birds. Kelp forests are very rich in biodiversity. The diversity of organisms in the North Sea is high, but it does vary according to region. Open waters in general are more diverse than downstream parts of rivers, estuaries.

Estuaries are special habitats, where the salt level — the salinity — is lower, which makes it less suitable to live in for many marine species. Humans and their activity also have a negative impact on the diversity of species. And the North Sea is heavily impacted by people. Because of its location, its long coastline, and the large number of rivers that empty into it, the North Sea has long been a vital route for travel and trade. There are also valuable natural resources — gas and oil — under the seabed.

This is why the North Sea is really important for the economy. For a long time, the North Sea has also been one of the most productive fishing areas in the world. But the North Sea’s great potential for making money comes at a great cost. Overfishing is causing the numbers of fish to decrease rapidly. Shipping contributes to introducing new, invasive species, and to high levels of pollution.

There is also pollution coming from land, this includes sewage and waste from factories and farms. Many plant and animal species have completely or partially disappeared over the past century because of pollution, and are struggling to make a comeback. But efforts are being made to restore the balance to the ecosystems and to reduce the negative impact on the area. The North Sea can still recover, if given a chance. And that would benefit both us and nature.