The “seven seas” has actually been supplied to explain the world’s an excellent water bodies for a long time. But there room actually about 50 water formations that deserve to be referred to as a “sea,” and they are quite varied when it comes to their size, location, and also ecosystems.

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Greek coast South Aegean

Historically people select to live by the sea for the weather, climate, or to be close to transportation routes or food.

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The expression “the 7 Seas” has actually been roughly for centuries, yet that term yes, really refers to different parts that the ocean and also several other big bodies of water. There room actually more than 7 seas in the world. However what renders a sea different from various other bodies the water?

That is not simple question come answer, since the meaning of a sea leaves some room for interpretation. In general, a sea is defined as a part of the ocean that is partially surrounded through land. Provided that definition, there are around 50 seas approximately the world. Yet that number has water body not always thought of together seas, such together the Gulf the Mexico and the Hudson Bay.

Moreover, in part cases, a sea is fully landlocked. The Caspian Sea is the most renowned example, despite this sea, i beg your pardon lies between Russia and Iran, is additionally referred to as the world’s largest lake. Other seas surrounded by land incorporate the Aral Sea and the Dead Sea. They contain saltwater and have been called seas for many years, yet many oceanographers and also geographers are an ext inclined to call them lakes.

Still, that pipeline dozens the water bodies the fit the traditional definition of a sea, also though they can be quite various from one another. A sea can be much more than 2.6 million square kilometers (1 million square miles) in area, such together the Caribbean Sea. Or, it deserve to be together tiny together the Sea that Marmara, which is less than 12,950 square kilometers (5,000 square miles) in area. This small Turkish sea connect the Aegean Sea and the black color Sea.

A sea can likewise be really warm for many of the year. The Red Sea, for instance, has an average temperature of approximately 30 degrees Celsius (86 levels Fahrenheit). It is also the saltiest sea, include 41 components of salt per 1,000 components of seawater. Seas can be fairly cold, too. The Greenland Sea, because that instance, has surface water the hovers close to the freezing mark most of the year.

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The range of the sizes, temperatures, and also locations the the Earth’s seas also method that the maritime ecosystems within every sea can vary considerably from one come the other. The Baltic Sea in Scandinavia is the world’s youngest sea having actually formed between 10 thousand and 15 thousand years back from glacial erosion. It consists of a distinctive mixture of saltwater and also freshwater, making that the biggest brackish water human body on the planet. Together a result, the Baltic Sea consists of a small, yet rare, variety of freshwater and saltwater plants and animals that have been may be to it is adapted to your brackish environment.

Not surprisingly, the diversity the the world’s seas likewise draws National geographical explorers, such as oceanographer Katy Croff Bell. She was component of the crew aboard the exploration vessel Nautilus, a ship that mutual its scientific discoveries in the Mediterranean Sea, the black color Sea, and also elsewhere with students approximately the world in virtual lessons and also chats. She states the seas—big and also small, cold and warm—can teach scientists about the rest of the world. “We’re walk to areas that have actually never to be explored to see what’s there,” Bell called MIT modern technology Review in 2015. “There room things we can’t even conceive of the end there, and it will take a long, long time to fully understand our very own planet.”