The Pacific Ocean is the largest ocean in the world. Among the four oceans, the area is the largest and the water body is the deepest. The area accounts for half of the whole ocean area, reaching more than1.800 million square kilometers; Its volume exceeds 720 million cubic kilometers and its average depth exceeds 4000 meters. The deepest part of Mariana Trench is11034m. The Pacific Ocean is also the ocean with the largest number of islands, with an island area of over 4.4 million square kilometers.
The Pacific Ocean has the highest water temperature, with an annual average surface water temperature of 19℃. The water temperature is the highest near 7 degrees north latitude, exceeding 28℃. The annual average water temperature in more than half of the Pacific Ocean is higher than 20℃, and that in a quarter of the Pacific Ocean is higher than 25℃.
The Pacific Ocean is also the ocean with the most trenches, volcanoes and earthquakes. There are 28 large trenches, which are distributed in a circle around the Pacific Ocean at the junction of shallow water and deep water ocean basins. There are more than 360 active volcanoes in many trenches, accounting for 85% of the total number of active volcanoes in the world. Earthquakes are frequent, accounting for 80% of the total number of earthquakes in the world.
The Pacific Ocean has its own complete ocean current system. Influenced by the wind belt on the earth, these ocean currents flow slowly in a certain direction, which has obvious influence on the climate in the flowing area. The famous cold currents in the Pacific Ocean include Thousand Island Cold Current (pro-tidal), California Cold Current, Peru Cold Current and East China Cold Current. The famous warm current is Kuroshio.
The Atlantic Ocean, the second ocean in the world, is the ocean between South America, North America, Europe, Africa and Antarctica. It borders the Arctic Ocean in the north, Antarctica in the south, and the waters of the Pacific Ocean and the Indian Ocean.
The Atlantic Ocean is the second largest ocean in the world, with an area of 9,337 square kilometers and an average depth of 3,627 meters. The deepest Puerto Rico trench is 8742 meters deep. All the ridges under the ocean are submerged below 3000 meters, and only a few ridges protrude from the ocean to form islands, so there are fewer islands than those in the Pacific Ocean. Most of the islands are concentrated in the northwest of the Caribbean. When Columbus mistook these islands for those near India, he gave them a very inappropriate name-"Indies", which was later called the West Indies.
The average surface temperature of the Atlantic Ocean is 16.9℃, which is lower than that of the Pacific Ocean and the Indian Ocean. However, the water temperature in equatorial waters is still as high as 26℃.
There are also several strong ocean currents in the Atlantic Ocean, which have a great influence on the climate in this area. For example, the famous Gulf Stream is one of the largest warm currents in the ocean, with a width of 43 ~ 108 nautical miles, a depth of 200 ~ 700 meters, a speed of 3 ~ 4 nautical miles per hour and a water temperature of 24℃, which has a great impact on the climate in Western Europe and Northern Europe. There is a famous Labrador cold current in the Atlantic Ocean.
Shipping in the Atlantic Ocean has a long history, and the earliest exploration activities in Europe began with sailing in the Atlantic Ocean. The wonderful "S" shaped coastline of the Atlantic Ocean inspired German meteorologist Wei Gena, who boldly put forward the famous theory of "continental drift".
Indian Ocean, the third ocean in the world, lies between Asia, Africa, Oceania and Antarctica. It borders Asia in the north, Oceania in the east, the Pacific Ocean in the southeast and the Atlantic Ocean in the southwest, covering an area of 7,465,438+10,000 square kilometers, making it the third ocean in the world.
Most of the Indian Ocean is located in the tropics, equator and tropic of Capricorn, and the annual average surface temperature is about 17℃, which is second only to that of the Pacific Ocean. The Indian Ocean current north of the equator is influenced by the South Asian monsoon, and its flow direction changes with the direction of the monsoon. In winter, the northeast wind blows and the ocean current flows counterclockwise to the west; In summer, the southwest wind blows and the ocean current flows clockwise to the east. This kind of ocean current that changes direction with the wind and season is called "monsoon ocean current". The Indian Ocean current in the southern hemisphere is roughly the same as that in the Pacific Ocean and Atlantic Ocean. The Southern Equatorial Warm Current, the Malagasy Warm Current, and the west wind drift and Western Australia Cold Current form a single counterclockwise circulation.
Along the northern coast of the Indian Ocean, the coastline is tortuous, and there are many bays and inland seas, among which the Red Sea, Persian Gulf, Arabian Sea, Bay of Bengal, Andaman Sea, Sawu Sea, Timor and Australian Bay are the largest. There are many mainland islands, volcanic islands and coral islands in the Indian Ocean.
Hurricanes in the Indian Ocean are world-famous. This kind of hurricane, like typhoon, is a tropical storm, which often brings violent storms and huge waves, causing great disasters.
The geographical location of the Indian Ocean is particularly important. It is the traffic artery connecting Asia, Africa, Europe and Oceania. Crossing the Straits of Malacca eastward, you can enter the Pacific Ocean; Westward bypass the Cape of Good Hope at the southern tip of Africa and reach the Atlantic Ocean; Northwest through the Red Sea, Suez Canal, you can contact the Mediterranean and lead to Europe. The countries along the northern coast of the Indian Ocean are rich in oil, which is also an important oil transportation artery.
The Arctic Ocean is the smallest ocean in the world, located in the Arctic Circle. It is the smallest and shallowest of the four oceans in the world, with an area of 1.365438+ 10,000 square kilometers and an average depth of only1.200m..
The Arctic Ocean is a very cold ocean. There is ice on the surface of the ocean all the year round, accounting for two-thirds of the total area of the Arctic Ocean, and the thickness is about 2 ~ 4 meters. On these ice layers, you can not only drive a car, but also land a heavy plane. The severe winter in the Arctic Ocean lasts for half a year, and the average temperature in the coldest season is around -40℃. The closer to the polar regions, the colder the climate and the thicker the ice. Near the top of the polar region, the ice layer is more than 30 meters thick.
The water temperature in the Arctic Ocean is very low, which is below 0℃ most of the time. Only in summer, in the waters near the mainland, the water temperature rises above 0℃, forming a coastal melting zone. Due to the influence of the North Atlantic warm current, several inland seas are formed in the Arctic Ocean.
There are many islands in the Arctic Ocean, second only to the Pacific Ocean, with a total area of 4 million square kilometers. The main islands are Greenland, Spitsbergen and Victoria. Due to the severe cold, there are few species of life in the Arctic Ocean. Plants are mainly lichens and mosses, and animals are white bears, walruses, seals, deer and whales. , but the number has been decreasing day by day.
The strategic position of the Arctic Ocean is very important. The route across the Arctic Ocean has greatly shortened the distance between Asia, Europe and North America. For example, from new york to Moscow, flying over the Arctic Ocean is about 1000 km shorter than crossing the Atlantic Ocean. The route of the Arctic Ocean has also greatly shortened the sea route between East and West. However, due to the bad weather in winter, there are many and thick ice layers and icebergs, so sailing is limited to warm seasons, and icebreakers are needed to sail.