San Francisco Bay is located off the coast of the United States and is part of the Pacific Ocean. It connects with the Golden Gate Strait, which is known throughout the world for its suspension bridge. This unique natural area is gradually decreasing due to human activities. About the San Francisco Bay, its features and unusual facts concerning it will be described in more detail in the article.
General Description
San Francisco Bay is one of the many bays of the vast Pacific Ocean. As mentioned earlier, this bay is connected to the ocean through the Golden Gate Strait. Basically, the water area is shallow - on an area of more than 100 km2 its depth does not exceed 10 meters, which is considered an extremely small value.
It should be noted that more than half of all river water entering the bay originates in the Sierra Nevada, Hamilton and Santa Cruz mountains. The largest river that carries its waters into this area is the San Joaquin. Most of the other rivers first fall intoSan Pablo Bay and Saisan Bay, which are part of San Francisco Bay. Currently, almost the entire water area near the coast, especially where migratory birds nest, is under the protection of the Ramsar Convention.
History
Answering the question of what San Francisco Bay is, we should turn to history. Natural conditions (river floods and soil erosion), as well as human activities, largely influenced the formation of the water area. Until 1850, the entire bay was navigable, until it was discovered that the sand carried by the rivers accumulates in places where the undercurrent of the bay is very weak. Because of this, its depth began to shrink quite sharply.
Almost immediately after that, the earth extracted from the pits, as well as the soil from the tunnels being built, began to pour along the bay. At that time, shallow bays, sand dunes, tidal pools and swampy soils had no owner, that is, they were considered "no man's land".
Formation
Gradually, the coastline began to expand, and the bay began to shrink. So, for 150 years its water area has decreased by almost one third. Today, significant areas of lowlands and swamps have been restored. Despite this, it is difficult to determine the exact area of San Francisco Bay.
Most of the water area that man destroyed as a result of his activities was built up. However, the structure of the soil here is such that it undergoes deformation. Because ofthat the area is seismically unstable and dangerous after even minor tremors, the ground begins to "liquefy".
Islands
There are five major islands in the San Francisco Bay Area. Each of them has its own bright and interesting history. On the island of Alameda there is a city of the same name, in which about 80 thousand people live. Scientists have established that in ancient times it was a peninsula, but due to the rise in the water level in the bay and the erosion of the soil, Alameda gradually turned into an island. Currently, it is connected to the mainland by bridges and two underwater tunnels, one of which was built in 1928.
Angel Island (Angel) is a historic landmark in California. In 1863, forts were built here to protect against the Confederates during the Civil War. The island can be reached by ferry, there is no other connection with it.
Yerba Buena is an island that hosted a military base for 120 years, until 1990. After the closure, a program was adopted to restore and preserve flora and fauna. Currently, there are 3 natural parks here.
Other islands
In the eastern part of San Francisco Bay lies Treasure Island. It is also known as "treasure island". This is an artificial island that was created between 1936 and 1937. It was "poured" to the opening of the exhibition "Golden Gate", which had an international level. It got its name from the book "Treasure Island" by R. L. Stevenson.
In the center of the bay is one of the most famous islands in the world - this is Alcatraz, also called Rock, which translates from English as "rock". In 1850, a fort was erected here, in which more than a hundred long-range guns were installed. It had practical protective functions. However, as unnecessary, in 1909 all the buildings were demolished, and on their foundation the building of a military prison was erected, which began to receive the first prisoners in 1912.
In 1934, Alcatraz became a federal prison, intended for especially dangerous and main enemies of the state. Also, those who had previously escaped from other prisons were placed here. Due to the water temperature in San Francisco Bay, which does not rise above 18 ° C even in summer, as well as the remoteness of the island from the mainland, escape becomes impossible.
In 1963, the prison was closed, and a museum was opened on its territory, which is very popular with tourists. Alcatraz Island itself has been designated a Historic National Monument.
Bridge
The most famous and recognizable part of the California Sea and San Francisco Bay is the Golden Gate Bridge. Built between 1933 and 1937, this building was the largest of its kind. A visual sensation is created, as if the bridge is hanging. This is due to the peculiarities of its type of construction. Its total length is 2737 m, and the height of the supports reaches 227 m, and this is just above the water. The mass of the structure has a volume of almost 900 thousand tons. Inat high tide, the distance from the surface of the water to the bridge reaches about 70 m.
The Golden Gate Bridge connected the main part of the city with Marin County and the suburb of Sausalito. It almost immediately became popular not only among locals, but also tourists. Everyone wanted to be photographed in front of him. Over time, this building has become a kind of hallmark of the city, by which almost everyone can recognize San Francisco.
Wadden Sea
The San Francisco Bay area belongs to the Wadden Seas. Watts is a series of marine shallow waters that are interrupted by shallow depths. Similar seas are located off the coast of Denmark, Germany and the Netherlands.
Its length is about 100 km2 from east to west and from 5 to 19 km from south to north. As mentioned earlier, the sea is shallow, its average depth reaches 10 meters. The inhabitants are striking in their diversity. Here you can find beluga whales, swordfish, manta rays, sailfish and several types of sharks. Sperm whales, blue and gray whales often swim to plankton fields in the bay during migration.
A variety of molluscs, echinoderms and crustaceans live at the bottom of the California Sea. Along the coast, it is quite common to find sea turtles that lay their eggs at certain times. There are also numerous nesting sites for waterfowl and common birds. Since 2005, the California Sea and San Francisco Bay have been protected by UNESCO andare world heritage. This amazing place impresses with its beautiful scenery, attracting numerous tourists all year round.
