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Bay

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A bay is a recessed body of water along a coastline. It connects directly to a much larger body of water. This main body might be an ocean, a lake, or even another bay.

DirkvdM baracoa panorama
DirkvdM baracoa panorama

Because land surrounds much of the water, bays offer unique environments. The surrounding land often reduces the strength of winds. It also blocks heavy waves from the open sea. This makes the water inside a bay much calmer than the open ocean.

There are many different ways a bay can be shaped. An open bay is widest at its mouth and is flanked by headlands. An enclosed bay has a mouth that is narrower than its widest part. This shape is usually created by at least one peninsula. A semi-enclosed bay is an open bay where islands in the mouth create narrower exit channels.

Some bays are even classified as back-barrier bays. These are semi-enclosed and are separated from open water by barrier islands or spits.

Bays form through several complex geological processes. Large bays often develop through plate tectonics. During the Paleozoic and early Mesozoic eras, the super-continent Pangaea broke apart. This happened along curved and indented fault lines. As the continents moved apart, they left large bays behind. The Bay of Bengal is the largest bay in the world, formed this way.

VyborgBay
VyborgBay

Other bays form through coastal erosion by rivers or glaciers. A bay formed by a glacier is specifically called a fjord. Rivers can also create bays called rias, which have more gradual slopes.

Erosion also plays a role based on the type of rock present. Deposits of softer rocks erode more rapidly than harder rocks. This rapid erosion forms the indentation of a bay. Meanwhile, the harder rocks erode more slowly and remain as headlands.

VyborgBay
VyborgBay

Some bays can even be nested within one another. For example, James Bay is an arm of the larger Hudson Bay in northeastern Canada. Some bays are large enough to have varied marine geology, such as the Bay of Bengal or Hudson Bay.

International rules help define exactly what a bay is. The United Nations Convention on the Law of the Sea uses specific measurements. A bay must be a well-marked indentation in the coastline. Its penetration must be large compared to the width of its mouth. Specifically, the area must be as large as or larger than a semi-circle drawn across the mouth. If the area is smaller than that semi-circle, it is called a bight instead.

These definitions lead to important legal distinctions called juridicial bays. A juridicial bay meets certain criteria to be considered inland waters. This means the waters belong to a state rather than being international waters. This status affects many things, such as the right to the seabed and its minerals. It also impacts control over fishing and the rights of seafarers.

DirkvdM baracoa panorama
DirkvdM baracoa panorama

It even determines if a coast is an international border.

Bays have played a massive role in human history. They provided early settlers with easy access to marine resources like fisheries. Because they provide safe anchorage, they later became vital for sea trade. This encouraged people to select them as locations for ports.

Some large inlets are called gulfs. A gulf is a large inlet from an ocean or sea into a landmass. Many gulfs, like the Persian Gulf or Gulf of Mexico, are major shipping areas.

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🖼️ Images & Media (3)
File:Aerial photograph of Langness and the bay at Castletown 13 February 2014 - geograph.org.uk - 3847162.jpg
Aerial photograph of Langness and the bay...
File:DirkvdM baracoa panorama.jpg
DirkvdM baracoa panorama.jpg
File:VyborgBay.jpg
VyborgBay.jpg
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