Geographical position
Most of the Indian Ocean lies in the southern hemisphere. In the north, it is bounded by Eurasia and has no connection to the Arctic Ocean. The shores are not very well cut. There are a few islands. Large islands are located only on the border of the ocean. The area with seas is 76.17 million km2 , the volume of water is 282.7 million km3 , the average depth is 3711 m. Seas and large bays: Red m., Arabian m., Persian hall, Andaman m., Bengal hall, B. Australian hall. It is bounded by Asia in the north, the Arabian Peninsula and Africa in the west, Indochina, the Sondh Islands and Australia in the east, and the Southern Ocean in the south. The boundary between the Indian Ocean and the Atlantic Ocean runs along the 20° meridian of the eastern longitude, between the Indian Ocean and the Pacific Ocean runs along the 147° meridian of the eastern longitude.
Bottom relief
The Rodrigues Island (Mascarene Archipelago) is home to a triple combination of the Central Indian and West Indian Ranges and the Australo-Antarctic Rise. The ridges consist of steep mountain chains cut perpendicularly or obliquely in relation to the axes of the chains by discharges and divide the basaltic bottom of the ocean into three segments, and their tops are usually extinguished volcanoes. The bottom of the Indian Ocean is covered by sediments from the Cretaceous and later periods, the thickness of which varies from several hundred meters to 2-3 km. The deepest of the numerous ocean trenches is the Yavansky trench (4,500 km long and 28 km wide). The rivers flowing into the Indian Ocean carry large quantities of sediment, especially from India, creating high sedimentary thresholds.
Climate
In this region, there are four climate zones stretched along the parallels. The first one, located to the north of 10° south latitude, is dominated by a monsoon climate with frequent cyclones moving towards the coasts. Temperatures above the ocean are 28-32°C in summer and 18-22°C in winter. The second zone (passatnaya) is located between 10 and 30 degrees south latitude. The southeasterly winds blow here all year round, particularly strong from June to September. The average annual temperature reaches 25 °C. The third climate zone lies between the 30th and 45th parallels, in subtropical and temperate latitudes. In summer the temperature here reaches 10-22°С, and in winter - 6-17°С. Between 45 degrees south latitude and Antarctica lies the fourth zone of sub-Antarctic and Antarctic climatic zones, which are characterized by strong winds. Temperatures range from -16°C to 6°C in winter and from -4°C to 10°C in summer.
Water characteristics
The water belt of the Indian Ocean between 10 degrees north latitude and 10 degrees South latitude is called the thermal equator, where the temperature of surface waters is 28-29 ° C. To the south of this zone, the temperature drops to -1 °C off the coast of Antarctica. In January and February, the ice along the coast of this continent thaws, huge blocks of ice break off from the ice cover of Antarctica and drift towards the open ocean.
To the north, the temperature characteristics of the waters are determined by monsoon air circulation. Temperature anomalies are observed here in summer when the Somali current cools surface waters to 21-23°C. In the eastern part of the ocean at the same latitude, the temperature of the waters is 28°C, and the highest point of temperature - about 30°C - has been recorded in the Persian Gulf and the Red Sea. The average salinity of oceanic waters is 34.8 ppm. The most saline waters of the Persian Gulf, the Red Sea, and the Arabian Sea are due to the intensive evaporation with a small amount of fresh water brought into the sea by rivers.
Indian Ocean countries
The Indian Ocean is home to many island nations. Among them: Madagascar, Seychelles, Maldives, Mauritius, Sri Lanka, Indonesia.
Countries located on the coast: Sudan, India, Somalia, Tanzania, Mozambique, Thailand, Australia, South Africa, Pakistan, and others.