One of the youngest known seas is the North Sea . It is a saltwater body considered a marginal sea within the Atlantic Ocean. Located west of the European continent between the United Kingdom, Germany, France, Belgium, the Netherlands, Denmark, Sweden, and Norway, it has a rectangular shape covering an area of ​​approximately 570,000 km² and a volume of 54,000–94,000 km³.
In this article we are going to tell you about all the characteristics, formation, biodiversity and threats of the North Sea.
Key features
This is a marginal sea of ​​the Atlantic Ocean, estimated to be 960 kilometers long at its longest point and 580 kilometers wide at its widest . It connects to the rest of the Atlantic Ocean via the Strait of Dover and the English Channel, and to the Baltic Sea via the Skagerrak Strait and the subsequent Kattegat Strait. Numerous islands are scattered throughout the sea, including the Frisian Islands, the Farne Islands, and other small islands and islets near its coasts.
The rivers that primarily feed this sea are the Rhine, the Glome, the Elbe, the Weser, the Dramen, the Ätran, the Thames, the Trent, and the Ems. Being a relatively young sea, it is shallow. In the northern part, it is somewhat deeper, but only reaches depths of 90 meters in some areas. The maximum estimated depth is 700 meters, located in the northern part of Norway . The waters are very cold and sometimes freeze. Ice floes can occasionally be seen floating on the surface.
The most normal thing is that during winter the waters of the North Sea surface reach 6 degrees on average, while in summer the temperature rises to 17 degrees. The highest salinity flow comes from the Atlantic and the lowest temperature and lowest salinity water comes from the Baltic. As is to be expected, the least salty areas of this sea are those located in the areas near the mouths of the rivers.
The coasts of the North Sea are different depending on the region where we are. Especially in the northern part and along the coast of Norway fjords, cliffs, pebble beaches, valleys and beaches with sand dunes are common. All these ecosystems are typical of the Norwegian coasts. However, in the eastern and western areas others with regular relief and some steep areas contrast.
Formation of the north sea
As we mentioned earlier, it is one of the youngest seas in the world. It is only about 3.000 years old in the coastal area. It began to grow after the breakup of the supercontinent Pangaea, as this separation created large landmasses that were fed by the rivers mentioned earlier. At the beginning of the Cenozoic era , the supercontinent had just broken apart, and the Atlantic Ocean had already formed.
It can be said that this sea formed in stages due to geological changes. During the Triassic and Jurassic periods , numerous geological formations and faults created the region where the highest areas are located today, leaving it in a state of formation. This resulted in some areas having a greater volume of water. During this formative period, the Earth's crust had not yet risen, nor had the British Isles yet formed.
Later, during the Oligocene epoch, the central and western parts of the European continent had already emerged from the sea. Almost all the waters that separated the Tethys Ocean were above water. Just 2.6 million years ago , during the Pliocene epoch , the North Sea Basin was already south of the Dogger Bank, forming part of Europe, with the Rhine flowing into its salty waters. Due to the various ice ages that followed, ice sheets formed and gradually retreated during the Pleistocene epoch.
Only 8.000 years ago the ice disappeared completely and the sea level began to rise. Due to the contribution of water from the rivers and the disappearance of the ice, the sea could begin to form completely. In addition, the rise in sea level caused the land bridge between Great Britain and France to be flooded and the English Channel and the evil of the North were connected.
Biodiversity of the North Sea
As expected, this sea is rich in biodiversity and is not only home to many animals but also a stopover for migratory species. We find a great number of mammals, such as the harbor seal, the hooded seal, the harbor porpoise, the ringed seal, right whales, and many other mammal species. As for fish, there are more than 230 different species, including cod, flatfish, spiny dogfish, whiting, and herring. This great variety of fish thrives thanks to the abundance of nutrients carried by the rivers and the presence of plankton.
We also find a large number of suitable ecosystems that offer perfect habitats for the nesting and residence of some seabirds and migratory birds. These estuaries are perfect for providing shelter to numerous species. Among the seabirds that take refuge in these estuaries are loons, razorbills, puffins, terns, and northern fulmars . In ancient times, the North Sea was much better known for its biodiversity than it is today. Over the centuries, biodiversity in this area has decreased significantly.
Threats
The human being is present in most of the threats of all the oceans and seas of the world. As you might expect, this case is no different. Following the discovery of the oil and natural gas reserves that exist under this sea floor, the North Sea has been the subject of intense commercial exploitation. All the countries around the North Sea have been increasingly exploiting fossil fuel resources and the coasts are enriched by the extraction of sand and gravel.
Due to these economic activities, marine biodiversity has been declining due to the introduction of machinery into natural habitats and high levels of pollution and overfishing . Some species have even disappeared, such as flamingos and the great auk. The latter is extinct worldwide.
I hope that with this information you can learn more about the North Sea and its characteristics.