An estuary is what? Short course of the school program

The estuary is a funnel-shaped mouth of a river with one sleeve, extending closer to the sea. When the deposit - earth and sand, brought by wind or water - is removed either by the sea current or by the tide, and the part of the sea adjacent to this place is deeper, an estuary is formed. Yenisei, Don and many other rivers have a estuary in the form of an estuary. The opposite concept of estuary in geography is delta. This is the mouth of the river, divided into streams. This part of the water flow is near the Nile, the Amazon and the Volga, but the latter, in turn, forms a estuary when it enters the Caspian Sea.

How does the estuary appear?

Usually the estuary of the river is the result of immersion in the water of one of the waterfront coastline. This process is accompanied by the flooding of its lower part. Tides have a strong impact on the estuary, resulting in the river channel fall salty (ocean and sea), as well as fresh (river) water. Tides often occur with such force that the flow of the stream is turned back, and salty and fresh water penetrate many kilometers into the earth. If such a tide falls on a rather narrow V-shaped estuary with very steep and high banks, the water level can rise so that a huge wave called boron forms. He in this case will penetrate deep into the earth, until he has completely squandered all his energy.

The largest estuaries

The estuary is a place convenient for navigation, since it is protected from all sides. In many areas even large cities are located. For example, Lisbon is located on the estuary of the River Tagus.

The largest world segment of this type is called La Plata. It is located between the countries of Uruguay and Argentina. There, such rivers flow into the sea as Paraguay and Parana. It is on the shore of the Estuary of La Plata that the cities of Montevideo and Buenos Aires are located.

Climatic conditions

The estuary is a place where the climate is very stable and rarely "pleases" with new and unexpected precipitation. For example, most often monsoon can prevail. It is a constant tropical wind. As a rule, they go from the land in the summer, and in the winter - from the sea. Summer in such conditions is somewhat cool - about 15 degrees. And also the described climatic conditions make it clear that the estuary is a site that can constantly be fed by the rains. An example of such territory is the Gulf of St. Lawrence. It is constantly visited by tourists and can always please with its landscapes.