The largest and most majestic ocean on the planet, which is in no way distinguished by its calm character. The name “Quiet” was given to it by the greatly mistaken Ferdinand Magellan, who during his journey did not observe any storms or any other excesses.
If we take the entire water surface of the Earth as 100%, the Pacific Ocean will occupy almost half of this amount - 46%. For comparison: the share of the Indian Ocean is only 20%. And if we conditionally unite all the earth’s land into one continent, its area will be less than the area of the Pacific Ocean.
The deepest point on the planet, the famous Mariana Trench, is an impressive place. If you imagine this depression as a mountain of equivalent height, it would rise higher than Everest. It is known that at least 20 species of oceanic animals live and thrive at the bottom of the depression. The average depth of the ocean is also impressive, almost 4300 m.
In addition to the Mariana Trench, there are several other points in the ocean with a depth of about 10 thousand km. These are the Tonga and Kermadec depressions, as well as the Philippine Trench.
The Pacific Ocean also leads in the number of islands located in it. There are more than 25 thousand of them in total. The other three oceans combined cannot boast of such an amount.
The entire area of the Pacific Ocean is divided into western and eastern. The western one is adjacent to Asia, the eastern one is adjacent to America.
When viewed from space, the Pacific Ocean resembles a triangle.
The time of the “official” discovery of the Pacific Ocean was the beginning of the 16th century. It was then that the Spaniard Vasco de Balboa was first struck by its greatness and power.
The unyielding nature of the ocean is evidenced by the fact that earthquakes and volcanic eruptions occur more often in its area than in any other place in the world. Seismically turbulent areas frame the Pacific Ocean almost entirely. On flooded and already dormant volcanoes, atolls are formed - islands based on corals.
The flora and fauna of the ocean are rich and varied. More than 100,000 species of animals call it home. This is three times the "population" of the Atlantic Ocean. There are more than a thousand species and subspecies of decapod crayfish alone.
Many underwater mountain ranges in the Pacific Ocean were formed as a result of volcanic eruptions. Thus, in particular, the Emperor Mountains appeared, representing a whole range.
The longest chain of coral islands, the Great Barrier Reef, is also located in the Pacific Ocean. It encircles the northeast coast of Australia.
Alas, some islands of the Pacific Ocean are not formed as a result of natural phenomena. In its northern waters grow so-called “garbage islands”, the basis of which is unrecycled waste - mainly plastic bottles.
Truly gigantic tsunamis are formed in the Pacific Ocean. The average speed of destructive waves can be about 750 kilometers per hour.
If all the water of the Pacific Ocean is distributed evenly over the surface of the planet, it will cover it completely, and the thickness of the water layer will exceed 2700 m.
One of the shipwrecks that occurred in 1992 in the Pacific Ocean greatly helped scientists in studying its currents. A Hong Kong ship sailing to the United States and loaded to the brim with plastic toys never made it to the States after being caught in a severe storm. But artificial turtles, beavers, frogs and the famous yellow ducks swam to different parts of the Earth, including Hawaii, Japan and Alaska.
The Pacific Ocean is also famous for its highest tides. Off the Korean coast, water can rise to 9 meters in height.
Surfers respect the Pacific Ocean for the height of its waves.
The most unusual monetary unit in the world was discovered on the islands of the Pacific Ocean - stone rings more than two meters high. Each of them reaches a weight of 15 tons. If you come to the island group of Yap and want to sell something there, it will be very problematic to transport such revenue for the goods. Unless it will be possible to stand next to her...
The average depth is 3988 m. The deepest point of the ocean (it is also the deepest point in the world) is located in the Mariana Trench and is called the Challenger Deep (11,022 m).
. Average temperature: 19-37°C. The widest part of the Pacific Ocean is located at equatorial-tropical latitudes, so surface water temperatures are significantly higher than in other oceans.
. Dimensions: area - 179.7 million sq. km, volume - 710.36 million sq. km.
To imagine how big the Pacific Ocean is, there are enough numbers: it occupies a third of our planet and makes up almost half of the World Ocean.
Salinity - 35-36 ‰.
Pacific Currents
Alaskan- washes the western coast of North America and reaches the Bering Sea. It spreads to great depths, right down to the bottom. Current speed: 0.2-0.5 m/s. Water temperature: 7-15°C.
East Australian- the largest off the Australian coast. It starts at the equator (Coral Sea) and runs along the east coast of Australia. Average speed is 2-3 knots (up to 7). Temperature - 25°C.
Kuroshio(or Japanese) - washes the southern and eastern shores of Japan, carrying the warm waters of the South China Sea to the northern latitudes. It has three branches: East Korean, Tsushima and Soya. Speed: 6 km/h, temperature 18-28°C.
North Pacific- continuation of the Kuroshio current. It crosses the ocean from west to east, and near the coast of North America it branches into the Alaskan (goes to the north) and California (to the south). Near the coast of Mexico, it turns and crosses the ocean in the opposite direction (North Trade Wind Current) - all the way to Kuroshio.
South Passatnoye- flows in the southern tropical latitudes, stretches from east to west: from the coast of South America (Galapagos Islands) to the coast of Australia and New Guinea. Temperature - 32°C. Gives rise to the Australian Current.
Equatorial countercurrent (or inter-trade current)- stretches from west to east between the North Passat and South Passat currents.
Cromwell's current- a subsurface countercurrent that passes under the South Passat. Speed 70-150 cm/sec.
Cold:
Californian- the western branch of the North Pacific Current, flows along the western coasts of the United States and Mexico. Speed - 1-2 km/h, temperature 15-26°C.
Antarctic Circumpolar (or Western Winds Current)— circles the entire globe between 40° and 50° S. latitude. Speed 0.4-0.9 km/h, temperature 12-15 °C. This current is often called the "Roaring Forties", as powerful storms rage here. The Peruvian Current branches off from it in the Pacific Ocean.
Peruvian Current (or Humboldt Current)- flows from south to north from the coast of Antarctica along the western coast of Chile and Peru. Speed 0.9 km/h, temperature 15-20 °C.
Underwater world of the Pacific Ocean
The flora and fauna of the underwater world in the Pacific Ocean is the richest and most diverse. Almost 50% of all living organisms in the World Ocean live here. The most densely populated area is considered to be the area near the Great Balier Reef.
All ocean wildlife is located according to climatic zones - in the north and south it is scarcer than in the tropics, but the total number of each species of animal or plant is greater here.
The Pacific Ocean produces more than half of the world's seafood catch. Of the commercial species, the most popular are salmon (95% of the world catch), mackerel, anchovies, sardines, horse mackerel, and halibut. There is limited whale fishing: baleen whales and sperm whales.
The richness of the underwater world is eloquently demonstrated by the following figures:
- more than 850 species of algae;
- more than 100 thousand species of animals (of which over 3800 species of fish);
- about 200 species of animals living at a depth of more than 7 thousand km;
- more than 6 thousand species of mollusks.
The Pacific Ocean is home to the largest number of endemics (animals that are found only here): dugongs, fur seals, sea otters, sea lions, sea cucumbers, polychaetes, leopard sharks.
The nature of the Pacific Ocean has only been studied about 10 percent. Every year scientists discover more and more new species of animals and plants. For example, in 2005 alone, more than 2,500 new species of mollusks and more than 100 species of crustaceans were discovered.
Pacific exploration
According to scientific research, the Pacific Ocean is the oldest on the planet. Its formation began in the Cretaceous period of the Mesozoic, that is, more than 140 million years ago. The exploration of the ocean began long before the advent of writing. People who lived on the shores of the greatest water area have been using the gifts of the ocean for thousands of years ago. Thus, Thor Heyerdahl's expedition on the Kon-Tiki balsa raft confirmed the scientist's theory that the islands of Polynesia could have been populated by people from South America who were able to cross the Pacific Ocean on the same rafts.
For Europeans, the history of ocean exploration is officially dated from September 15, 1513. On this day, traveler Vasco Nunez de Balboa first saw the expanse of water stretching to the horizon, and dubbed it the South Sea.
According to legend, the ocean received its name from F. Magellan himself. During his trip around the world, the great Portuguese for the first time circled South America and found himself in the ocean. Having sailed along it for more than 17 thousand kilometers and without experiencing a single storm during all this time, Magellan christened the ocean the Pacific. It was only later research that proved him wrong. The Pacific Ocean is actually one of the most turbulent oceans. It is here that the largest tsunamis occur, and typhoons, hurricanes and storms occur here more often than in other oceans.
From then on, active exploration of the largest ocean on the planet began. We list only the most significant discoveries:
1589 - A. Ortelius publishes the world's first detailed map of the ocean.
1642-1644 - the ocean conquers A. Tasman and opens a new continent - Australia.
1769-1779 - three voyages around the world by D. Cook and exploration of the southern part of the ocean.
1785 - voyage of J. La Perouse, exploration of the southern and northern parts of the ocean. The mysterious disappearance of the expedition in 1788 still haunts the minds of researchers.
1787-1794 - the journey of A. Malaspina, who compiled a detailed map of the west coast of America.
1725-1741 - two Kamchatka expeditions led by V.I. Bering and A. Chirikov, study of the northern and northwestern parts of the ocean.
1819-1821 - trip around the world by F. Bellingshausen and M. Lazarev, discovery of Antarctica and islands in the southern part of the ocean.
1872-1876 - the world's first scientific expedition to study the Pacific Ocean was organized on the corvette Challenger (England). Maps of depths and bottom relief were compiled, and a collection of ocean flora and fauna was collected.
1949-1979 - 65 scientific voyages of the ship "Vityaz" under the flag of the USSR Academy of Sciences (measuring the depth of the Mariana Trench and detailed maps underwater terrain).
1960 - first dive to the bottom of the Mariana Trench.
1973 - creation of the Pacific Oceanological Institute (Vladivostok)
Since the 90s of the twentieth century, a comprehensive study of the Pacific Ocean has begun, which combines and systematizes all the data obtained. Currently, the priority areas are geophysics, geochemistry, geology and commercial use of the ocean floor.
Since the discovery of the Challenger Deep in 1875, only three people have descended to the very bottom of the Mariana Trench. The last dive took place on March 12, 2012. And the brave diver was none other than the famous film director James Cameron.
Many representatives of the fauna of the Pacific Ocean are characterized by gigantism: giant mussels and oysters, the tridacna clam (300 kg).
There are over 25 thousand islands in the Pacific Ocean, more than in all other oceans combined. Here is also the oldest island on the planet - Kauai, whose age is estimated at 6 million years.
More than 80% of tsunamis are “born” in the Pacific Ocean. The reason for this is large number underwater volcanoes.
The Pacific Ocean is full of secrets. There are many mystical places here: the Devil's Sea (near Japan), where ships and planes disappear; the bloodthirsty island of Palmyra, where everyone who remains there perishes; Easter Island with its mysterious idols; Truk Lagoon, where the largest military equipment cemetery is located. And in 2011, a sign island was discovered near Australia - Sandy Island. It appears and disappears, as evidenced by numerous expeditions and Google satellite photos.
The so-called Garbage Continent was discovered in the north of the ocean. This is a large garbage heap containing over 100 million tons of plastic waste.
The largest and most ancient of all oceans. Its area is 178.6 million km2. It can easily accommodate all the continents combined, which is why it is sometimes called the Great. The name “Pacific” is associated with the name of F., who traveled around the world and sailed through the Pacific Ocean under favorable conditions.
This ocean is truly great: it occupies 1/3 of the surface of the entire planet and almost 1/2 of the area. The ocean has an oval shape, and it is especially wide.
The peoples inhabiting the Pacific coasts and islands have been sailing the ocean for a long time and exploring its riches. Information about the ocean was accumulated as a result of the voyages of F. Magellan, J. . The beginning of its wide study was laid in the 19th century by the first round-the-world Russian expedition of I.F. . Currently, a special one has been created for the study of the Pacific Ocean. In recent years, new data have been obtained about its nature, its depth has been determined, currents and the topography of the bottom and ocean have been studied.
The southern part of the ocean from the shores of the Tuamotu Islands to the shores is an area of calm and stable. It was for this calm and silence that Magellan and his companions called the Pacific Ocean. But west of the Tuamotu Islands the picture changes dramatically. Calm weather is rare here; stormy winds usually blow, often turning into... These are the so-called southern squalls, especially fierce in December. Tropical cyclones are less frequent but more intense. They arrive at the beginning of autumn from, at the northern tip they turn into warm westerly winds.
The tropical waters of the Pacific Ocean are clean, transparent and have medium salinity. Their deep dark blue color amazed observers. But sometimes the waters here turn green. This is due to the development of marine life. The equatorial part of the ocean has favorable weather conditions. The temperature over the sea is about 25°C and remains almost unchanged throughout the year. Winds of moderate strength blow here. At times there is complete calm. The sky is clear, the nights are very dark. The balance is especially stable in the island zone. In the calm belt there are frequent heavy but short-lived showers, mainly in the afternoon. Hurricanes are extremely rare here.
The warm waters of the ocean contribute to the work of corals, of which there are many. The Great Reef stretches along the eastern coast of Australia. This is the largest “ridge” created by organisms.
The western part of the ocean is under the influence of the monsoons with their sudden vagaries. Terrible hurricanes arise here and... They are especially ferocious in the northern hemisphere between 5 and 30°. Typhoons are frequent from July to October, with up to four per month in August. They originate in the area of the Caroline and Mariana Islands and then “make raids” on the shores, and. Since the western tropical part of the ocean is hot and rainy, the islands of Fiji, the New Hebrides, and New Hebrides are not without reason considered one of the most unhealthy places on the globe.
The northern regions of the ocean are similar to the southern ones, only as if in a mirror image: circular rotation of the waters, but if in the southern part it is counterclockwise, then in the northern part it is clockwise; unstable weather in the west, where typhoons enter further north; cross currents: North Passat and South Passat; in the north of the ocean there is little floating ice, since the Bering Strait is very narrow and protects the Pacific Ocean from the influence of the Arctic Ocean. This distinguishes the north of the ocean from its south.
The Pacific Ocean is the deepest. Its average depth is 3980 meters, and its maximum reaches 11022 m. The ocean coast is in a seismic zone, as it is the boundary and place of interaction with other lithospheric plates. This interaction is accompanied by terrestrial and underwater and.
Bottom relief: East Pacific Rise, Northeast, Northwestern, Central, Eastern, Southern and other basins, deep-sea trenches: Aleutian, Kurile, Mariana, Philippine, Peruvian and others.
Inhabitants: a large number of unicellular and multicellular microorganisms; fish (pollock, herring, salmon, cod, sea bass, beluga, chum salmon, pink salmon, sockeye salmon, chinook salmon and many others); seals, seals; crabs, shrimp, oysters, squid, octopus.
: 30-36.5 ‰.
Currents: warm - , North Pacific, Alaskan, South Trade Wind, East Australian; cold - Californian, Kuril, Peruvian, Western winds.
Additional information: The Pacific Ocean is the largest in the world; crossed it for the first time in 1519, the ocean was called “Pacific”, because during the entire three months of the journey they did not encounter a single storm; The Pacific Ocean is usually divided into northern and southern regions, the border of which runs along the equator.
General information about the Pacific Ocean
It is believed that the first person to visit the Pacific Ocean on a ship was Magellan . In 1520, he circumnavigated South America and saw new expanses of water. Since during the entire journey Magellan's team did not encounter a single storm, the new ocean was named " Quiet".
But even earlier, in 1513, the Spaniard Vasco Nunez de Balboa headed south from Colombia to a place where he was told there was rich country with a big sea. Having reached the ocean, the conquistador saw an endless expanse of water stretching to the west, and called it " South Sea".
Animal world
The ocean is famous for its rich flora and fauna. It is home to about 100 thousand species of animals. Such diversity is not found in any other ocean. For example, the second largest ocean by area is inhabited by “only” 30 thousand species of animals.
There are several places in the Pacific Ocean where the depth exceeds 10 km. This is the famous Kermadec and Tonga depressions. Scientists were able to describe 20 species.
Half of all seafood consumed by humans is caught in the Pacific Ocean. Among the 3 thousand species of fish, industrial-scale fishing is open for herring, mackerel, etc.
Climate
The large extent of the ocean from north to south quite logically explains the diversity of climatic zones - from equatorial to Antarctic. The most extensive zone is the equatorial one. Throughout the year, the temperature here does not drop below 20 degrees. Temperature fluctuations throughout the year are so small that we can safely say that it is always +25 there. There is a lot of precipitation, more than 3,000 mm. per year. Very frequent cyclones are typical.
The amount of precipitation is greater than the amount of water evaporating. Rivers that bring more than 30 thousand m³ into the ocean annually fresh water, make surface waters less saline than other oceans.
Relief of the bottom and islands of the Pacific Ocean
The bottom topography is extremely varied. Located in the east East Pacific Rise, where the terrain is relatively flat. In the center there are basins and deep-sea trenches. The average depth is 4,000 m, and in some places exceeding 7 km. The bottom of the center of the ocean is covered with products of volcanic activity with increased content copper, nickel and cobalt. The thickness of such deposits is separate areas may be 3 km. The age of these rocks begins with the Jurassic and Cretaceous periods.
At the bottom there are several long chains of seamounts formed as a result of the action of volcanoes: d ora of the Emperor, Louisville and the Hawaiian islands. There are about 25,000 in the Pacific Ocean. This is more than in all other oceans combined. Most of them are located south of the equator.
Islands are classified into 4 types:
- Continental Islands. Very closely related to the continents. Includes New Guinea, the islands of New Zealand and the Philippines;
- High Islands. Appeared as a result of underwater volcanic eruptions. Many of the modern high islands have active volcanoes. For example Bougainville, Hawaii and Solomon Islands;
- Coral raised platforms;
The last two types of islands are huge colonies of coral polyps, forming and.
- This ocean is so huge that its maximum width is equal to half the earth's equator, i.e. more than 17 thousand km.
- Animal world large and varied. Even now, new animals unknown to science are regularly discovered there. So, in 2005, a group of scientists discovered about 1000 species of decapod cancer, two and a half thousand mollusks and more than a hundred crustaceans.
- The deepest point on the planet is in the Pacific Ocean at. Its depth exceeds 11 km.
- The tallest mountain in the world is located in the Hawaiian Islands. It's called Muana Kea and is extinct. The height from base to top is about 10,000 m.
- Located on the ocean floor Pacific Volcanic Ring of Fire, which is a chain located along the perimeter of the entire ocean.
Contents of the article
PACIFIC OCEAN, the largest body of water in the world, the area of which is estimated at 178.62 million km 2, which is several million square kilometers more than the earth's land area and more than twice the area of the Atlantic Ocean. The width of the Pacific Ocean from Panama to the eastern coast of Mindanao is 17,200 km, and the length from north to south, from the Bering Strait to Antarctica is 15,450 km. It extends from the western coasts of North and South America to the eastern coasts of Asia and Australia. From the north, the Pacific Ocean is almost completely closed by land, connecting with the Arctic Ocean through the narrow Bering Strait (minimum width 86 km). In the south it reaches the shores of Antarctica, and in the east its border with the Atlantic Ocean is located at 67° west. – meridian of Cape Horn; in the west, the border of the South Pacific Ocean with the Indian Ocean is drawn at 147° E, corresponding to the position of Cape South-East in the south of Tasmania.
Regionalization of the Pacific Ocean.
Usually the Pacific Ocean is divided into two regions - North and South, bordering along the equator. Some experts prefer to draw the boundary along the axis of the equatorial countercurrent, i.e. approximately 5°N. Previously, the Pacific Ocean was more often divided into three parts: northern, central and southern, the boundaries between which were the Northern and Southern Tropics.
Individual areas of the ocean located between islands or land protrusions have their own names. The largest water areas of the Pacific basin include the Bering Sea in the north; Gulf of Alaska in the northeast; the Gulf of California and Tehuantepec in the east, off the coast of Mexico; the Gulf of Fonseca off the coast of El Salvador, Honduras and Nicaragua and somewhat to the south - the Gulf of Panama. There are only a few small bays off the west coast of South America, such as Guayaquil off the coast of Ecuador.
In the western and southwestern Pacific Ocean, numerous large islands separate the main waters from many interisland seas, such as the Tasman Sea southeast of Australia and the Coral Sea off its northeastern coast; Arafura Sea and Gulf of Carpentaria north of Australia; the Banda Sea north of Timor; the Flores Sea north of the island of the same name; Java Sea north of Java Island; Gulf of Thailand between the Malacca and Indochina peninsulas; Bac Bo Bay (Tonkin) off the coast of Vietnam and China; Makassar Strait between the islands of Kalimantan and Sulawesi; the Molucca and Sulawesi seas, respectively, to the east and north of Sulawesi Island; finally, the Philippine Sea east of the Philippine Islands.
A special area in the southwest of the northern half of the Pacific Ocean is the Sulu Sea within the southwestern part of the Philippine archipelago, where there are also many small bays, bays and semi-enclosed seas (for example, the Sibuyan, Mindanao, Visayan Seas, Manila Bay, Lamon and Leite). The East China and Yellow Seas are located off the eastern coast of China; the latter forms two bays in the north: Bohaiwan and West Korean. The Japanese islands are separated from the Korean Peninsula by the Korea Strait. In the same northwestern part of the Pacific Ocean, several more seas stand out: the Inland Sea of Japan among the southern Japanese islands; the Sea of Japan to their west; to the north is the Sea of Okhotsk, which is connected to the Sea of Japan by the Tatar Strait. Even further north, immediately south of the Chukotka Peninsula, is the Gulf of Anadyr.
The greatest difficulties are caused by drawing the border between the Quiet and Indian Oceans in the Malay Archipelago region. None of the proposed boundaries could satisfy botanists, zoologists, geologists and oceanographers at the same time. Some scientists consider the so-called dividing line. the Wallace Line passing through the Makassar Strait. Others propose drawing the border through the Gulf of Thailand, the southern part of the South China Sea and the Java Sea.
Characteristics of the coast.
The shores of the Pacific Ocean vary so much from place to place that it is difficult to single out any common features. With the exception of the far south, the Pacific coast is framed by a ring of dormant or sporadically active volcanoes known as the “Ring of Fire.” Most of the coastline is formed by high mountains, so that the absolute surface elevations change sharply at a close distance from the coast. All this indicates the presence of a tectonically unstable zone along the periphery of the Pacific Ocean, the slightest movements within which cause strong earthquakes.
In the east, the steep slopes of the mountains approach the very shore of the Pacific Ocean or are separated from it by a narrow strip of coastal plain; This structure is typical for the entire coastal zone, from the Aleutian Islands and the Gulf of Alaska to Cape Horn. Only in the far north does the Bering Sea have low-lying shores.
In North America, isolated depressions and passes occur in the coastal mountain ranges, but in South America the majestic chain of the Andes forms an almost continuous barrier along the entire length of the continent. The coastline here is quite flat, and bays and peninsulas are rare. In the north, the bays of Puget Sound and San Francisco and the Strait of Georgia are most deeply cut into the land. On most of the South American coastline, the coastline is flattened and almost nowhere forms bays and bays, with the exception of the Gulf of Guayaquil. However, in the far north and far south of the Pacific Ocean there are areas that are very similar in structure - the Alexandra Archipelago (southern Alaska) and the Chonos Archipelago (off the coast of southern Chile). Both areas are characterized by numerous islands, large and small, with steep shores, fjords and fjord-like straits that form secluded bays. The rest of the Pacific coast of North and South America, despite its great length, offers only limited opportunities for navigation, since there are very few convenient natural harbors there, and the coast is often separated by a mountain barrier from the interior of the mainland. In Central and South America, mountains impede communication between west and east, isolating a narrow strip of the Pacific coast. In the north Pacific Ocean, the Bering Sea is frozen for most of the winter, and the coast of northern Chile is a desert for a considerable length; this area is famous for its deposits of copper ore and sodium nitrate. The areas located in the far north and far south of the American coast - the Gulf of Alaska and the area around Cape Horn - have gained a bad reputation for their stormy and foggy weather.
The west coast of the Pacific Ocean is significantly different from the east; The coasts of Asia have many bays and bays, in many places forming a continuous chain. There are numerous protrusions of different sizes: from such large peninsulas as Kamchatka, Korean, Liaodong, Shandong, Leizhoubandao, Indochina, to countless capes separating small bays. There are also mountains along the Asian coast, but they are not very high and are usually somewhat distant from the coast. More importantly, they do not form continuous chains and do not act as a barrier isolating coastal areas, as is observed in east coast ocean. In the west, many large rivers flow into the ocean: Anadyr, Penzhina, Amur, Yalujiang (Amnokkan), Yellow River, Yangtze, Xijiang, Yuanjiang (Hongha - Red), Mekong, Chao Phraya (Menam). Many of these rivers have formed vast deltas where large populations live. The Yellow River carries so much sediment into the sea that its deposits formed a bridge between the shore and a large island, thus creating the Shandong Peninsula.
Another difference between the east and west coasts of the Pacific Ocean is that the west coast is lined with a huge number of islands of varying sizes, often mountainous and volcanic. These islands include the Aleutian, Commander, Kuril, Japanese, Ryukyu, Taiwan, Philippine islands (their total number exceeds 7,000); finally, between Australia and the Malacca Peninsula there is a huge cluster of islands, comparable in area to the mainland, on which Indonesia is located. All of these islands have mountainous terrain and are part of the Ring of Fire that surrounds the Pacific Ocean.
Only a few large rivers of the American continent flow into the Pacific Ocean - mountain ranges prevent this. The exception is some rivers in North America - Yukon, Kuskokwim, Fraser, Columbia, Sacramento, San Joaquin, Colorado.
Bottom relief.
The Pacific Ocean Trench has a fairly constant depth throughout its entire area - approx. 3900–4300 m. The most notable elements of the relief are deep-sea depressions and trenches; elevations and ridges are less pronounced. Two uplifts stretch from the coast of South America: the Galapagos in the north and the Chilean, which stretches from the central regions of Chile to approximately 38° S. latitude. Both of these rises connect and continue south towards Antarctica. As another example, mention can be made of the rather extensive underwater plateau over which the Fiji and Solomon islands rise. Deep-sea trenches are often located close to the coast and parallel to it, the formation of which is associated with the belt of volcanic mountains framing the Pacific Ocean. The most famous include the deep-sea Challenger Basin (11,033 m) southwest of Guam; Galatea (10,539 m), Cape Johnson (10,497 m), Emden (10,399 m), three Snell basins (named after the Dutch ship) with depths from 10,068 to 10,130 m and the Planet basin (9,788 m) near the Philippine Islands; Ramapo (10,375 m) south of Japan. The Tuscarora depression (8513 m), which is part of the Kuril-Kamchatka Trench, was discovered in 1874.
A characteristic feature of the Pacific Ocean floor are numerous underwater mountains - the so-called. guyots; their flat tops are located at a depth of 1.5 km or more. It is generally accepted that these are volcanoes that previously rose above sea level and were subsequently washed away by waves. To explain the fact that they are now at great depth, we have to assume that this part of the Pacific Trench is experiencing subsidence.
The bed of the Pacific Ocean is composed of red clays, blue silts and crushed fragments of corals; Some large areas of the bottom are covered with globigerina, diatoms, pteropods and radiolarians. IN bottom sediments Manganese nodules and shark teeth are found. There are a lot of coral reefs, but they are common only in shallow waters.
The salinity of water in the Pacific Ocean is not very high and ranges from 30 to 35‰. Temperature fluctuations are also quite significant depending on latitudinal position and depth; surface layer temperatures in the equatorial belt (between 10° N and 10° S) are approx. 27°C; at great depths and in the extreme north and south of the ocean, the temperature is only slightly above the freezing point of sea water.
Currents, tides, tsunamis.
The main currents in the northern part of the Pacific Ocean include the warm Kuroshio or Japan Current, which turns into the North Pacific (these currents play the same role in the Pacific Ocean as the Gulf Stream and North Atlantic Current system in Atlantic Ocean); cold California Current; Northern Trade Wind (Equatorial) Current and cold Kamchatka (Kuril) Current. In the southern part of the ocean there are warm currents: the East Australian and South Passat (Equatorial); cold currents of the Western Winds and the Peruvian. In the Northern Hemisphere, these main current systems move clockwise, and in the Southern Hemisphere, counterclockwise. Tides are generally low for the Pacific Ocean; the exception is Cook Inlet in Alaska, which is famous for its exceptionally large rise of water during high tides and is second in this regard only to the Bay of Fundy in the northwest Atlantic Ocean.
When earthquakes or large landslides occur on the seabed, waves called tsunamis occur. These waves travel enormous distances, sometimes more than 16 thousand km. In the open ocean they are small in height and long in extent, but when approaching land, especially in narrow and shallow bays, their height can increase to 50 m.
History of the study.
Navigation in the Pacific Ocean began long before the beginning of recorded human history. However, there is evidence that the first European to see the Pacific Ocean was the Portuguese Vasco Balboa; in 1513 the ocean opened before him from the Darien Mountains in Panama. In the history of Pacific Ocean exploration there are such famous names, like Ferdinand Magellan, Abel Tasman, Francis Drake, Charles Darwin, Vitus Bering, James Cook and George Vancouver. Later, scientific expeditions on the British ship Challenger (1872–1876) and then on the Tuscarora ships played a major role. "Planet" And "Discovery".
However, not all sailors who crossed the Pacific Ocean did so intentionally and not all were well equipped for such a voyage. It could well be that the winds and ocean currents picked up primitive boats or rafts and carried them to distant shores. In 1946, the Norwegian anthropologist Thor Heyerdahl put forward a theory according to which Polynesia was settled by settlers from South America who lived in Peru in pre-Inca times. To confirm his theory, Heyerdahl and five companions sailed almost 7 thousand km across the Pacific Ocean on a primitive raft made of balsa logs. However, although his voyage of 101 days proved the possibility of such a journey in the past, most oceanographers still do not accept Heyerdahl's theories.
In 1961, a discovery was made indicating the possibility of even more amazing contacts between the inhabitants of the opposite shores of the Pacific Ocean. In Ecuador, in a primitive burial at the Valdivia site, a fragment of ceramics was discovered, strikingly similar in design and technology to the ceramics of the Japanese islands. Other ceramic items belonging to these two spatially separated cultures were also found and also have noticeable similarities. Judging by archaeological data, this transoceanic contact between cultures located at a distance of approximately 13 thousand km occurred ca. 3000 BC.
