The geomorphological characteristics of the Indian Ocean continent are that the average width of the continental shelf is narrower than that of the Atlantic Ocean, and the slope of the continental slope is also smaller. In addition, the large number and wide distribution of continental rises or sea platforms are also prominent features of the Indian Ocean continental margin landforms. Some of the Indian Ocean continental rises are formed by turbidity currents or sliding collapse of the continental slope, which accumulate a large amount of clastic material on the edge of the abyssal plain; some are formed by the differential subsidence of part of the continent. There are the Agulhas Platform and the Mozambique Platform on the coast of Africa, and the Madagascar Platform in the south of Madagascar. On the coast of Australia are the Exmouth Platform and the Natcheralist Platform. On the west side of the Indian peninsula is the Chagos-Lakdive Platform. It is precisely because of these sea platforms that the continental landforms of the Indian Ocean have distinctive features.
Tropical oceanic and monsoonal climate are obvious characteristics of the Indian Ocean climate. We know that most of the Indian Ocean is located in the tropical and subtropical ranges, so the vast sea area changes under the influence of temperature, and the distribution of temperature also changes with changes in latitude. Therefore, distinct climate characteristics of the Indian Ocean are formed.
The climate of the Indian Ocean is changed by the distribution of temperature. The average temperature throughout the year in the vast sea area north of 40° south latitude of the Indian Ocean is 15 to 28°C. The annual temperature in the equatorial zone is 28°C, and in some sea areas it is as high as 30°C. The Indian Ocean has higher temperatures than the Pacific and Atlantic oceans at the same latitude, so it is called a tropical ocean.
In the Indian Ocean, the distribution of temperature changes with latitude. The annual average temperature in the equatorial region is about 28°C. In the northern part of the Indian Ocean, the summer temperature is 25 to 27 degrees Celsius, the winter temperature is 22 to 23 degrees Celsius, and the annual average temperature is about 25 degrees Celsius. Among them, the summer temperatures in the Persian Gulf and Red Sea on the east and west sides of the Arabian Peninsula often reach over 30°C, while the temperature along the coast of Somalia in the hottest season is generally less than 25°C. The former has a lot to do with the baking of the surrounding dry and hot land. For the latter, the southwesterly wind blows away the surface water and causes the deep cold water to rise, which in turn causes the temperature to drop.
In the southern Indian Ocean, temperatures also change with latitude. In summer, the temperature in the southern Indian Ocean is 25-27°C near 20° south latitude, 20-22°C near 30° south latitude, about 15°C near 40° south latitude, and about 0°C near 60° south latitude; in winter, The temperature in the southern Indian Ocean is 22-23℃ near 20° south latitude, 15-17℃ near 30° south latitude, 12-13℃ near 40° south latitude, and as low as -10℃ near 60° south latitude. Due to the uneven distribution of temperature, the climate of the Indian Ocean is also subject to great changes.
The climate characteristics of the Indian Ocean are also reflected in precipitation. The equatorial zone has the most abundant precipitation, with annual precipitation ranging from 2000 to 3000mm. In addition, the seasonal distribution of precipitation is relatively even: in the northern part of the Indian Ocean, the annual precipitation is generally about 2000mm, and 2/3 of the precipitation is concentrated in the summer when the southwesterly wind prevails, while in the winter when the northeasterly wind prevails, the precipitation is less, and it is a tropical monsoon distribution area. The surface of the Red Sea and the western part of the Arabian Sea have little precipitation throughout the year, with annual precipitation of about 100 to 200 mm. They are tropical desert climate areas. In the vast areas of the southern Indian Ocean, annual precipitation is generally around 1000mm. It can be seen that except for the equatorial zone where the Indian Ocean is relatively rich, the annual precipitation in the north and south Indian Ocean is relatively evenly distributed.