Pacific Ocean also called the Great, because it is the largest on the planet. The ocean covers almost the same area as all other oceans combined (Fig. 17). On its area - 178.6 million km 2 - all the continents would be freely located and at the same time there would be room for one more Africa.

Northern pacific border conventionally drawn through the Bering Strait from the coast of Eurasia to the coast of North America. In the south, the ocean washes the coast of Australia and reaches the coast of Antarctica. Here its boundaries are drawn conditionally, along the meridians. The Pacific Ocean lies in almost all geographic zones of the Earth, with the exception of the Arctic.

The central regions of the ocean lie in the equatorial belt, and the equator itself divides the ocean into approximately two equal parts. Therefore, to the north and south of the equator, the nature of the Pacific Ocean is similar. At the same time, in the western and eastern parts of the same geographical zone, the nature of the ocean differs markedly (Fig. 18). These differences are due, in particular, to sea currents.

Differences in nature the western and eastern parts of the ocean are also determined by the outlines of the coastline of the continents. In Eurasia, it is very dissected and has numerous bays, islands and marginal seas. These bays and seas often cut deep into the land. Therefore, the western part of the Pacific Ocean is more influenced by the continents than the eastern part.

The Pacific Ocean washes coasts of Eurasia, Australia, Northern and South America. And although they are at a distance of many thousands of kilometers from each other, the waters of the Pacific Ocean not only separate the continents and states, but also connect them. After all, the most important transport routes linking the countries of Asia, Australia and America run across the ocean. material from the site

The diversity of the nature of the Pacific Ocean is primarily due to its geographical position.

On this page, material on the topics:

• Pacific Message Brief Grade 2

• Position of the Pacific Ocean in relation to other oceans

• Geographic position of the Pacific Ocean Post

• The position of the ocean in relation to the continents

• Pacific Report for Grade 2

Questions about this item:

The Great, or Pacific, Ocean is the greatest ocean on Earth. It accounts for about half (49%) of the area and more than half (53%) of the volume of the waters of the World Ocean, and the surface area is equal to almost a third of the entire surface of the Earth as a whole. In terms of the number (about 10 thousand) and the total area (more than 3.5 million km2) of islands, it ranks first among the rest of the oceans of the Earth.

In the northwest and west, the Pacific Ocean is bounded by the shores of Eurasia and Australia, in the northeast and east by the shores of North and South America. The border with the Arctic Ocean is drawn through the Bering Strait along the Arctic Circle. The southern border of the Pacific Ocean (as well as the Atlantic and Indian) is considered the northern coast of Antarctica. When identifying the Southern (Antarctic) Ocean, its northern boundary is drawn along the waters of the World Ocean, depending on the change in the regime of surface waters from temperate latitudes to Antarctic. It runs approximately between 48 and 60°S. (Fig. 3).

Rice. 3. The boundaries of the oceans

Borders with other oceans south of Australia and South America are also conditionally drawn along the water surface: with the Indian Ocean - from Cape South East Point approximately along 147 ° E, from Atlantic Ocean- from Cape Horn to the Antarctic Peninsula. In addition to a wide connection with other oceans in the south, there is communication between the Pacific and the northern part of the Indian Ocean through the interisland seas and the straits of the Sunda archipelago.

The area of ​​the Pacific Ocean from the Bering Strait to the coast of Antarctica is 178 million km2, the volume of water is 710 million km3.

The northern and western (Eurasian) shores of the Pacific Ocean are dissected by seas (there are more than 20 of them), bays and straits that separate large peninsulas, islands and entire archipelagos of continental and volcanic origin. The coasts of Eastern Australia, the southern part of North America and especially South America are usually straight and difficult to access from the ocean. With a huge surface area and linear dimensions (more than 19 thousand km from west to east and about 16 thousand km from north to south), the Pacific Ocean is characterized by a weak development of the continental margin (only 10% of the bottom area) and a relatively small number of shelf seas.

Within the intertropical space, the Pacific Ocean is characterized by accumulations of volcanic and coral islands.

Introduction

Pacific Ocean- the largest and oldest of all oceans. Its area is 178.6 million km2. It can freely accommodate all the continents and islands combined, which is why it is sometimes called the Great. The name "Pacific" is associated with the name of F. Magellan, who made a round-the-world trip and sailed across the Pacific Ocean under favorable weather conditions.

This ocean is really great: it occupies 1/3 of the surface of the entire planet and almost 1/2 of the area of ​​the World Ocean. The ocean has an oval shape, it is especially wide at the equator.

The peoples inhabiting the Pacific shores and islands have long sailed the ocean and mastered its riches. Information about the ocean was accumulated as a result of the voyages of F. Magellan, J. Cook. The beginning of its wide study was laid in the 19th century by the first round-the-world Russian expedition of I.F. Kruzenshtern. A special international organization for the study of the Pacific Ocean has now been established. Behind last years new data on its nature have been obtained, the depth has been determined, currents, bottom relief, biological resources of the ocean.

Geographical position

Great or Pacific Ocean - the greatest ocean of the Earth. It accounts for about half (49%) of the area and more than half (53%) of the volume of the waters of the World Ocean, and the surface area is equal to almost a third of the entire surface of the Earth as a whole. In terms of the number (about 10 thousand) and the total area (more than 3.5 million km 2) of islands, it ranks first among the rest of the oceans of the Earth.

In the northwest and west, the Pacific Ocean is bounded by the shores of Eurasia and Australia, in the northeast and east by the shores of North and South America. The border with the Arctic Ocean is drawn through the Bering Strait along the Arctic Circle. The southern border of the Pacific Ocean (as well as the Atlantic and Indian) is considered the northern coast of Antarctica. When identifying the Southern (Antarctic) Ocean, its northern boundary is drawn along the waters of the World Ocean, depending on the change in the regime of surface waters from temperate latitudes to Antarctic. It runs approximately between 48 and 60°S.

ocean borders

Borders with other oceans south of Australia and South America are also conditionally drawn along the water surface: with the Indian Ocean - from Cape South East Point at about 147 ° E, with the Atlantic Ocean - from Cape Horn to the Antarctic Peninsula. In addition to a wide connection with other oceans in the south, there is communication between the Pacific and the northern part of the Indian Ocean through the interisland seas and the straits of the Sunda archipelago.

The area of ​​the Pacific Ocean from the Bering Strait to the coast of Antarctica is 178 million km2, the volume of water is 710 million km3.

The northern and western (Eurasian) shores of the Pacific Ocean are dissected by seas (there are more than 20 of them), bays and straits that separate large peninsulas, islands and entire archipelagos of continental and volcanic origin. The coasts of Eastern Australia, the southern part of North America and especially South America are usually straight and difficult to access from the ocean. With a huge surface area and linear dimensions (more than 19 thousand km from west to east and about 16 thousand km from north to south), the Pacific Ocean is characterized by a weak development of the continental margin (only 10% of the bottom area) and a relatively small number of shelf seas.

Within the intertropical space, the Pacific Ocean is characterized by accumulations of volcanic and coral islands.

The relief of the ocean floor

There are still different points of view on the question of the time of the formation of the Pacific Ocean in its modern form, but, obviously, by the end of the Paleozoic era, a vast reservoir already existed on the site of its basin, as well as the ancient pro-continent Pangea, located approximately symmetrically with respect to the equator . At the same time, the formation of the future Tethys Ocean began in the form of a huge bay, the development of which and the invasion of Pangea subsequently led to its disintegration and the formation of modern continents and oceans.

The bed of the modern Pacific Ocean is formed by a system of lithospheric plates bounded from the ocean by mid-ocean ridges, which are part of the global system of mid-ocean ridges of the World Ocean. These are the East Pacific Rise and the South Pacific Ridge, which, reaching a width of up to 2,000 km in places, join together in the southern part of the ocean and continue to the west, into the Indian Ocean. The East Pacific Ridge, extending to the northeast, to the coast of North America, in the Gulf of California region, connects with the system of continental rift faults of the California Valley, the Yosemite Trench and the San Andreas Fault. The median ridges of the Pacific Ocean, in contrast to the ridges of other oceans, do not have a clearly defined axial rift zone, but are characterized by intense seismicity and volcanism with a predominance of ejecta of ultrabasic rocks, i.e., they have features of a zone of intensive renewal of the oceanic lithosphere. Throughout the entire length of the median ridges and adjacent parts of the plates are crossed by deep transverse faults, which are also characterized by the development of modern and, especially, ancient intra-plate volcanism. Located between the median ridges and bounded by deep-sea trenches and transitional zones, the vast bed of the Pacific Ocean has a complexly dissected surface, consisting of a large number of basins with a depth of 5000 to 7000 m or more, the bottom of which is composed of oceanic crust covered with deep-sea clays, limestones and silts of organic origin. . The relief of the bottom of the basins is predominantly hilly. The deepest basins (about 7000 m or more): Central, West Mariana, Philippine, South, Northeast, East Caroline.

Basins, archipelagos and islands

The basins are separated from each other or crossed by arched uplifts or blocky ridges, on which volcanic structures are planted, often crowned with coral structures within the intertropical space. Their peaks protrude above the water in the form of small islands, often grouped into linearly elongated archipelagos. Some of them are still active volcanoes, spewing basaltic lava flows. But for the most part, these are already extinct volcanoes built on coral reefs. Some of these volcanic mountains are located at a depth of 200 to 2000 m. Their peaks are leveled by abrasion; the position deep under water is obviously associated with the lowering of the bottom. Formations of this type are called guyots.

Of particular interest among the archipelagos of the Central Pacific Ocean are the Hawaiian Islands. They form a chain 2500 km long, stretched north and south of the Tropic of the North, and are the peaks of huge volcanogenic massifs rising from the ocean floor along a powerful deep fault. Their visible height is from 1000 to 4200 m, and the underwater one is approximately 5000 m. internal structure And appearance The Hawaiian Islands are a typical example of oceanic intraplate volcanism.

The Hawaiian Islands are the northern edge of the huge island group of the central Pacific Ocean, collectively called "Polynesia". The continuation of this group up to about 10°S. are the islands of Central and Southern Polynesia (Samoa, Cook, Society, Tabuai, Marquesas, etc.). These archipelagos, as a rule, are elongated from the northwest to the southeast, along the lines of transform faults. Most of them are of volcanic origin and are composed of strata of basaltic lava. Some are crowned with wide and gentle volcanic cones 1000-2000 m high. The smallest islands in most cases are coral buildings. Numerous clusters of small islands, located mainly north of the equator, in the western part of the Pacific lithospheric plate, have similar features: the Mariana, Caroline, Marshall and Palau islands, as well as the Gilbert archipelago, which partially enters the southern hemisphere. These groups of small islands are collectively known as Micronesia. All of them are of coral or volcanic origin, are mountainous and rise hundreds of meters above sea level. The coasts are surrounded by surface and underwater coral reefs, which greatly impede navigation. Many small islands are atolls. Near some of the islands there are deep ocean trenches, and to the west of the Mariana Archipelago there is a deep-water trench of the same name, which belongs to the transition zone between the ocean and the Eurasian mainland.

In the part of the Pacific Ocean bed adjacent to the American continents, small isolated volcanic islands are usually scattered: Juan Fernandez, Cocos, Easter, etc. The largest and most interesting group is the Galapagos Islands, located near the equator near the coast of South America. This is an archipelago of 16 large and many small volcanic islands with peaks of extinct and active volcanoes up to 1700 m high.

The transitional zones from the ocean to the continents are distinguished by the structure of the ocean floor and the features of tectonic processes both in the geological past and at the present time. They encircle the Pacific Ocean in the west, north and east. In different parts of the ocean, the processes of formation of these zones proceed differently and lead to different results, but everywhere they are very active both in the geological past and at the present time.

From the side of the ocean floor, the transition zones are limited by arcs of deep-sea trenches, in the direction of which the lithospheric plates move and the oceanic lithosphere sinks under the continents. Within the transition zones, the structure of the ocean floor and marginal seas is dominated by transitional types of the earth's crust, and oceanic types of volcanism are replaced by mixed effusive-explosive volcanism of subduction zones. Here we are talking about the so-called "Pacific Ring of Fire", which encircles the Pacific Ocean and is characterized by high seismicity, numerous manifestations of paleovolcanism and volcanic landforms, as well as the existence within its limits of more than 75% of the planet's currently active volcanoes. Basically, this is a mixed effusive-explosive volcanism of medium composition.

The southern region of the Pacific transitional zone northeast of Australia is distinguished by great complexity. It extends from Kalimantan to New Guinea and further south to 20°S, fringing the Sohul-Queensland shelf of Australia from the north. This whole section of the transition zone is a complex combination of deep-sea trenches with depths of 6000 m or more, submarine ridges and island arcs, separated by basins or areas of shallow water.

Off the east coast of Australia, between New Guinea and New Caledonia, lies the Coral Sea. From the east, it is limited by a system of deep-water trenches and island arcs (New Hebrides, etc.). The depths of the basin of the Coral and other seas of this transitional area (the Fiji Sea and especially the Tasman Sea) reach 5000-9000 m, their bottom is composed of an oceanic or transitional type of crust.

The hydrological regime of the northern part of this area favors the development of corals, which are especially common in the Coral Sea. On the Australian side, it is limited by a unique natural structure - the Great Barrier Reef, which stretches along the continental shelf for 2300 km and in the southern part reaches a width of 150 km. It consists of individual islands and entire archipelagos, built of coral limestone and surrounded by underwater reefs of living and dead coral polyps. Narrow channels crossing the Great Barrier Reef lead to the so-called Great Lagoon, the depth of which does not exceed 50 m.

The transitional zone of the eastern part of the Pacific Ocean, facing the continents of North and South America, differs significantly from its western margin. There are no marginal seas or island arcs. From the south of Alaska to Central America stretches a strip of a narrow shelf with mainland islands. Along the western coast of Central America, as well as from the equator along the margins of South America, there is a system of deep-sea trenches - the Central American, Peruvian and Chilean (Atakama) with maximum depths of more than 6000 and 8000 m, respectively. Obviously, the process of formation of this part of the ocean and neighboring continents proceeded in interaction deep-sea trenches and continental lithospheric plates that existed at that time. North America moved over and closed the trenches on its way to the west, and the South American Plate moved the Atacama Trench to the west. In both cases, as a result of the interaction of oceanic and continental structures, there was a collapse into folds, uplift of the marginal parts of both continents and the formation of powerful suture zones - the North American Cordilleras and the Andes of South America. Each of these structural zones is characterized by intense seismicity and manifestation of mixed types of volcanism. OKLeontiev found it possible to compare them with the underwater ridges of the island arcs of the western transitional zone of the Pacific Ocean.

Climate and hydrological conditions

The Pacific Ocean extends between 60° north and south latitude. In the north, it is almost closed by the land of Eurasia and North America, separated from each other only by the shallow Bering Strait with the smallest width of 86 km, connecting the Bering Sea of ​​the Pacific Ocean with the Chukchi Sea, which is part of the Arctic Ocean.

Eurasia and North America extend south as far as the Tropic of the North in the form of vast massive landmasses, which are the centers of the formation of continental air, capable of influencing the climate and hydrological conditions of neighboring parts of the ocean. South of the Tropic of the North, the land acquires a fragmentary character; to the coast of Antarctica, its large land areas are only Australia in the southwest of the ocean and South America in the east, especially its extended part between the equator and 20 ° S. latitude. South of 40°S The Pacific Ocean, together with the Indian and Atlantic, merge into a single water surface, not interrupted by large areas of land, over which oceanic air of temperate latitudes is formed, and where Antarctic air masses freely penetrate.

The Pacific Ocean reaches its greatest width (almost 20 thousand km) within the tropical equatorial space, i.e. in that part of it, where during the year the thermal energy of the sun is most intensively and regularly supplied. In this regard, the Pacific Ocean receives more solar heat during the year than other parts of the World Ocean. And since the distribution of heat in the atmosphere and on the water surface depends not only on the direct distribution of solar radiation, but also on air exchange between land and water surface and water exchange between different parts of the World Ocean, it is quite clear that the thermal equator over the Pacific Ocean is shifted to the north. hemisphere and runs approximately between 5 and 10 ° N, and the northern part of the Pacific Ocean is generally warmer than the southern.

pressure systems

Let us consider the main baric systems that determine the meteorological conditions (wind activity, precipitation, air temperature), as well as the hydrological regime of surface waters (systems of currents, temperature of surface and subsurface waters, salinity) of the Pacific Ocean during the year. First of all, this is the near-equatorial depression (calm zone), somewhat extended towards the northern hemisphere. This is especially pronounced in the summer of the northern hemisphere, when an extensive and deep baric depression with a center in the Indus River basin is established over the strongly heated Eurasia. In the direction of this depression, streams of humid, unstable air rush from the subtropical centers. high pressure both northern and southern hemispheres. Most of the northern half of the Pacific Ocean at this time is occupied by the North Pacific maximum, along the southern and eastern periphery of which monsoons blow towards Eurasia. They are associated with heavy rainfall, the amount of which increases towards the south. The second monsoon flow moves from the southern hemisphere, from the side of the tropical high pressure zone. In the northwest, there is a weakened western transfer towards North America.

IN southern hemisphere, where it is winter at this time, strong westerly winds, carrying air from temperate latitudes, cover the waters of all three oceans south of the 40 ° S parallel. almost to the coast of Antarctica, where they are replaced by east and southeast winds blowing from the mainland. Western transfer operates in these latitudes of the southern hemisphere and in summer time but with less force. Winter conditions in these latitudes are characterized by heavy precipitation, storm winds, and high waves. With a large number of icebergs and floating sea ​​ice travel in this part of the world ocean threatens with great dangers. It is not for nothing that navigators have long called these latitudes the “roaring forties”.

At the corresponding latitudes in the northern hemisphere, the western transport is also the dominant atmospheric process, but due to the fact that this part of the Pacific Ocean is closed by land from the north, west and east, in winter there is a slightly different meteorological situation than in the southern hemisphere. With the western transport, cold and dry continental air enters the ocean from the side of Eurasia. It is involved in the closed system of the Aleutian Low, which is formed over the northern part of the Pacific Ocean, is transformed and carried to the coast of North America by southwestern winds, leaving abundant precipitation in the coastal zone and on the slopes of the Cordilleras of Alaska and Canada.

Wind systems, water exchange, features of the topography of the ocean floor, the position of the continents and the outlines of their coasts affect the formation of the surface currents of the ocean, and they, in turn, determine many features of the hydrological regime. In the Pacific Ocean, with its vast dimensions, within the intratropical space, there is a powerful system of currents generated by the trade winds of the northern and southern hemispheres. In accordance with the direction of movement of the trade winds along the margins of the North Pacific and South Pacific Ocean maxima facing the equator, these currents move from east to west, reaching a width of more than 2000 km. The North Trade Wind flows from the shores of Central America to the Philippine Islands, where it divides into two branches. The southern part spreads over the interisland seas and partly feeds the surface inter-trade countercurrent that runs along the equator and to the north of it, advancing towards the Central American Isthmus. The northern, more powerful branch of the North Trade Wind Current goes to the island of Taiwan, and then enters the East China Sea, skirting the Japanese islands from the east, gives rise to a powerful system of warm currents in the northern part of the Pacific Ocean: this is the Kuroshio Current, or the Japanese Current, moving at a speed of 25 to 80 cm/s. Near the island of Kyushu, the Kuroshio forks, and one of the branches enters the Sea of ​​Japan under the name of the Tsushima Current, the other goes out into the ocean and follows the eastern coast of Japan, until at 40 ° N. latitude. it is not pushed to the east by the cold Kuril-Kamchatka countercurrent, or Oyashio. The continuation of Kuroshio to the east is called the Kuroshio Drift, and then the North Pacific Current, which is directed to the coast of North America at a speed of 25-50 cm / s. In the eastern part of the Pacific Ocean, north of the 40th parallel, the North Pacific Current branches into the warm Alaska Current, heading towards the shores of South Alaska, and the cold California Current. The latter, following along the shores of the mainland, flows south of the tropic into the North Equatorial Current, closing the northern circulation of the Pacific Ocean.

Most of the Pacific Ocean north of the equator is dominated by high surface water temperatures. This is facilitated by the large width of the ocean in the intertropical space, as well as the system of currents that carry the warm waters of the Northern Equatorial Current to the north along the coasts of Eurasia and neighboring islands.

The Northern Tradewind current carries water with a temperature of 25 ... 29 ° C all year round. The high temperature of surface waters (up to approximately 700 m depth) persists within Kuroshio to almost 40°N. (27 ... 28 °С in August and up to 20 °С in February), as well as within the North Pacific Current (18 ... 23 °С in August and 7 ... 16 °С in February). A significant cooling effect on the northeast of Eurasia up to the north of the Japanese islands is exerted by the cold Kamchatka-Kuril Current, which originates in the Bering Sea, which in winter is intensified by cold waters coming from the Sea of ​​Okhotsk. From year to year, its power varies greatly depending on the severity of winters in the Bering and Okhotsk Seas. Area Kuril Islands and the islands of Hokkaido, one of the few islands in the North Pacific with ice in winter. At 40° N when meeting with the Kuroshio current, the Kuril current plunges to a depth and flows into the North Pacific. In general, the temperature of the waters of the northern part of the Pacific Ocean is higher than in the southern part at the same latitudes (5 ... 8 ° C in August in the Bering Strait). This is partly due to limited water exchange with the Arctic Ocean due to the threshold at the Bering Strait.

The Southern Equatorial Current moves along the equator from the shores of South America to the west and even enters the northern hemisphere up to about 5°N. In the area of ​​the Moluccas, it branches: the bulk of the water, together with the North Equatorial Current, enters the system of the Intertrade Countercurrent, and the other branch penetrates into the Coral Sea and, moving along the coast of Australia, forms a warm East Australian current, which flows into the current off the coast of Tasmania. Western winds. The temperature of surface waters in the South Equatorial Current is 22...28 °С, in the East Australian in winter from north to south it varies from 20 to 11 °С, in summer - from 26 to 15 °С.

Pacific Ocean in more, than other parts of the World Ocean, is the scene of the birth of the atmospheric process, known as tropical cyclones or hurricanes. These are vortices of small diameter (no more than 300-400 km) and high speed (30-50 km/h). They form within the tropical convergence zone of the trade winds, as a rule, during the summer and autumn of the northern hemisphere and move first in accordance with the direction of the prevailing winds, from west to east, and then along the continents to the north and south. For the formation and development of hurricanes, a vast expanse of water is required, heated from the surface to at least 26 ° C, and atmospheric energy, which would impart translational motion to the formed atmospheric cyclone. The features of the Pacific Ocean (its dimensions, in particular, the width within the intratropical space, and the maximum surface water temperatures for the World Ocean) create conditions over its water area that contribute to the origin and development of tropical cyclones.

The passage of tropical cyclones is accompanied by catastrophic phenomena: destructive winds, strong waves on the high seas, heavy rains, flooding of the plains on adjacent land, floods and destruction leading to severe disasters and loss of life. Moving along the coasts of the continents, the most powerful hurricanes go beyond the intratropical space, transforming into extratropical cyclones, sometimes reaching great strength.

The main area of ​​origin of tropical cyclones in the Pacific Ocean is south of the Tropic of the North, east of the Philippine Islands. Moving initially to the west and northwest, they reach the shores of Southeast China (in Asian countries, these eddies bear the Chinese name "typhoon") and move along the continent, deviating towards the Japanese and Kuril Islands.

The branches of these hurricanes, deviating to the west south of the tropic, penetrate into the interisland seas of the Sunda archipelago, into the northern part of the Indian Ocean and cause destruction in the lowlands of Indochina and Bengal. Hurricanes originating in the southern hemisphere north of the Southern Tropic move towards the coasts of Northwest Australia. There they carry the local name "BILLY-BILLY". Another center of tropical hurricane origin in the Pacific Ocean is located off the western coast of Central America, between northern tropic and the equator. From there, hurricanes rush to the coastal islands and coasts of California.

In the first years of the new millennium, an increase in the frequency of tropical cyclones (typhoons) near the Asian and North American coasts of the Pacific Ocean, as well as an increase in their power, was noted. This applies not only to the Pacific, but also to other oceans of the Earth. This phenomenon may be one of the consequences of global warming. The increased warming of the surface waters of the oceans in tropical latitudes also enhances atmospheric energy, which ensures the forward movement, speed of movement and the destructive power of hurricanes.

Animal and plant world

More than half of the living matter of the entire World Ocean of the Earth is concentrated in the waters of the Pacific Ocean. This applies to both plants and animals. The organic world as a whole is distinguished by species richness, antiquity, and a high degree of endemism.

The fauna, totaling up to 100 thousand species, is characterized by mammals that live mainly in temperate and high latitudes.A representative of toothed whales, the sperm whale, has a mass distribution, and several species of striped whales from toothless whales. Their fishing is strictly limited. Separate genera of the eared seal family (sea lions) and fur seals are found in the south and north of the ocean. Northern fur seals are valuable fur-bearing animals, the trade of which is strictly controlled. In the northern waters of the Pacific Ocean, there are also very rare sea lions (from eared seals) and walrus, which has a circumpolar range, but is now on the verge of extinction.

The fish fauna is very rich. In tropical waters there are at least 2000 species, in the northwestern seas - about 800 species. The Pacific Ocean accounts for almost half of the world's fish catch. The main fishing areas are the northern and central parts of the ocean. The main commercial families are salmon, herring, cod, anchovies, etc.

The predominant mass of living organisms inhabiting the Pacific Ocean (as well as other parts of the World Ocean) are invertebrates that live at different levels of ocean waters and at the bottom of shallow waters: these are protozoa, coelenterates, arthropods (crabs, shrimps), mollusks (oysters, squids , octopuses), echinoderms, etc. They serve as food for mammals, fish, seabirds, but also constitute an essential component of marine fisheries and are objects of aquaculture.

Pacific Ocean thanks to high temperatures its surface waters in tropical latitudes, is especially rich various types corals, including those with a calcareous skeleton. In no other ocean is there such an abundance and variety of coral structures of various types as in the Pacific.

The basis of plankton is made up of unicellular representatives of the animal and plant world. There are almost 380 species in the phytoplankton of the Pacific Ocean.

The greatest wealth of the organic world is typical for areas where the so-called upwelling is observed (the rise to the surface of deep waters rich in minerals) or mixing of waters with different temperatures occurs, which creates favorable conditions for the nutrition and development of phyto- and zooplankton, which feed on fish and other animals of the nekton. In the Pacific, upwelling areas are concentrated along the coasts of Peru and in divergence zones in subtropical latitudes, where there are areas of intensive fishing and other trades.

whale sperm whale

eared seal

Anchovy

Sea lion

"El Niño"

Against the background of normal, annually recurring conditions, the Pacific Ocean is characterized by a phenomenon that disrupts the usual rhythm of circulation and hydrological processes and is not observed in other parts of the World Ocean. It manifests itself at intervals of 3 to 7 years and entails a violation of the usual environmental conditions within the intertropical space of the Pacific Ocean, affecting the life of living organisms, including the population of the coastal regions of the land. It consists in the following: at the end of November or in December, i.e. shortly before Christmas (why the phenomenon received the popular name "El Niño", which means "Holy Child"), for reasons that have not yet been elucidated, there is a weakening of the southern trade wind and, consequently, a weakening of the South Trade Wind and the influx of relatively cold waters to the shores of South America and to the west of it. At the same time, winds usually unusual for these latitudes begin to blow from the northwest towards the southern hemisphere, carrying relatively warm waters to the southeast, intensifying the Equatorial countercurrent. This disrupts the upwelling phenomenon both in the zone of intratropical divergence and off the coast of South America, which, in turn, leads to the death of plankton, and then the death of fish and other animals that feed on it.

The El Niño phenomenon has been regularly observed since the second half of the 19th century. It has been established that in many cases it was accompanied by a violation of environmental conditions not only in the ocean, but also on vast areas of adjacent land: an anomalous increase in precipitation in the arid regions of South America and, conversely, droughts in the island and coastal regions of Southeast Asia and Australia. The consequences of El Niño on 1982-1983 and 1997-1998 are considered especially severe, when this unfavorable phenomenon lasted for several months.

As you know, about 70% of our planet is covered with water. A larger volume is occupied by the largest water body - the Pacific Ocean. Its geographical position is quite interesting. Let's get to know him in more detail.

Pacific Ocean: geographical location

The Pacific Ocean is considered the most unique natural object on our planet due to its features and size. What is the difference geographical position the Pacific Ocean? It is located in all hemispheres of our planet:

In the west - between Australia and Eurasia.

In the east - between South and North America.

In the south - washes Antarctica.

The size of the Pacific Ocean is one third of the entire surface of the Earth. It occupies half of the world's oceans.

External Description

The Pacific Ocean has oval elongated coastlines from northwest to southeast and wide outlines in tropical zones. The straightness of the coast can be seen near the American coast, and the dissection - near the Eurasian land.

The largest ocean includes the marginal seas of Asia. The waters of the Pacific conceal a large number of islands and archipelagos.

Scales

The description of the geographical location of the Pacific Ocean always traditionally begins with its scale. To be precise, Pacifica's waters occupy 49.5% of the planet's water surface, which means that it contains 53% of the total water volume. From west to east, the water surface stretches for 19 thousand km, and from north to south - more than 16 thousand. Most ocean waters are located in the southern latitudes, and a minority - in the northern part of the Earth.

History

The Pacific Ocean is interesting for its history. The geographical position at all latitudes for a long time did not give scientists the opportunity to check where the deepest place of Pacifica is located.

In 1951, an expedition of British scientific researchers on board the Challenger calculated the maximum depth of the Pacific Ocean. According to calculations made using an echo sounder, it was 10,863 meters. But after 6 years, these data were refuted by a Soviet group of scientists. The research ship Vityaz, headed by Alexander Dmitrievich Dobrovolsky, recorded the maximum depth of the Challenger Abyss at 11,034 meters. As of today, the correct figure is 10,994 meters corrected by +/- 40 meters.

What is the geographic location of the Pacific Ocean

The difference between the Pacific and other oceans is obvious. The Pacific Ocean, whose geographical position is very wide, borders on the Arctic Ocean, where the Bering Strait plays the role of a boundary. The boundary with the Atlantic Ocean is visible from Cape Horn (68°04'W) to the Antarctic Peninsula. Geographical position of the Pacific and Indian Oceansalso intersects. The border of two water bodies runs north of Australia - between the Strait of Malacca and the Andaman Sea; along the south coast of Sumatra and about. Java, between the boundaries of the Savu and Bali seas to the western part of the Arafura Sea.

The Pacific Ocean, whose geographical position is so interesting, is recognizable by the circulation of the atmosphere and water, and by the nature of the topography of its bottom.

Seas

The bays, straits and seas of the Pacific Ocean make up almost 32 million square kilometers. km, which is 18% of its total area. Most of the seas are concentrated in its western part, off the Eurasian coast: the Sea of ​​Japan, the Sea of ​​Okhotsk, the Yellow Sea, the Philippine Sea, the Bering Sea, and the East China Sea. Many Pacific seas wash the shores of Australia: Solomon, Fiji, Coral, New Guinea, Tasmanovo. Cold Antarctica also has seas that are subordinate to the Pacific Ocean: Ross, Amundsen, Durville, Somov, Bellingshausen. The shores of South and North America do not have seas, but they are washed by the Pacific bays: Panama, Alaska, California.

Pacific Ocean: the geographical position of the islands

The Pacific is rich in islands, and in this competition it has no equal among other oceans. Several thousand small plots of land in Oceania were formed as a result of volcanic eruptions. Many of them were overgrown with corals, after which they sank into the water, leaving behind atolls and reefs. In the Pacific Ocean there are several of the largest islands in the world: Kalimantan and New Guinea. Asia also has islands large sizes: Kuriles, Sakhalin, Commander, Japanese, Philippine, Sunda, Hainan, Taiwan and others. In Antarctica there are the Shetland Islands and the Land of Alexander the First, the Palmer archipelago. Off the coast of South and North America - Aleutian, Vancouver, Tierra del Fuego, Queen Charlotte Islands and others.

mysterious ocean

The world's oceans contain the waters of four oceans. But only one of them exists at once in all latitudes of the world, and his name is Quiet. Its scale, size, depth and the presence of seas, archipelagos, islands make the expanse of water mysterious and special. Many secrets hide in the depths of the ocean, which we have yet to learn...

TOPIC 1. PACIFIC OCEAN

LESSON 59 GEOGRAPHICAL POSITION. BOTTOM RELIEF. CLIMATE AND WATER

Target:

deepen and systematize students' knowledge about the features of nature. the oceans; to form the ability to determine the geographical position of the Pacific Ocean, to explain the features of its nature; improve skills in working with thematic maps of the atlas;

develop the ability to implement methods of rational learning activities: draw up a purposeful description of the object according to a standard plan;

educate cognitive activity, interest in the study of the topic, independence; to form a value attitude to the natural resources of the World Ocean, ecological consciousness.

Equipment: physical map of the world, atlases, textbooks, contour maps, computer, multimedia projector, multimedia presentation.

Lesson type: assimilation of new knowledge

Expected results: students will be able to name the characteristic features of the geographical location and nature of the Pacific Ocean; find and show on the map known geographical objects - seas, bays, straits, currents; give examples of bottom relief forms, currents, islands.

DURING THE CLASSES

I. ORGANIZATIONAL MOMENT

II. UPDATING OF BASIC KNOWLEDGE AND SKILLS

Reception "Blitsoprosk"

What are the parts of the world's oceans?

What is the ratio of the areas of the oceans to each other?

What is the largest ocean?

· What features of the structure of the earth's crust and bottom topography are characteristic of all oceans?

III. MOTIVATION OF LEARNING AND COGNITIVE ACTIVITIES

Reception "Problem question"

Despite the unity of the waters of the World Ocean, its components have certain natural features that you should find out in the following lessons.

The first object of our study is the Pacific Ocean.

Among all the oceans of the Earth, this ocean has every right to be called a unique geographical feature.

What do you think is the uniqueness of the Pacific Ocean?

(Student answers.)

Indeed, this is a unique geographical object of our planet. On its area - 178.7 million km2 - all the continents would freely fit, and at the same time there would be room for one more Africa! It is the largest, deepest and most ancient among the oceans of the Earth.

However, the list of facts about its natural features does not end there.

Today our work will be directed to the study of the geographical position, bottom topography, climate and waters of the Earth's greatest ocean.

IV. STUDY NEW MATERIAL

1. Familiarization with the plan for the study of the oceans

(See Lesson Supplementary Resources.)

2. Geographical location and dimensions

Working with the World Ocean map, physical card of the Pacific Ocean, a plan of the characteristics of the geographical position of the ocean, a multimedia presentation.

Tasks

1) Using the maps of the atlas, determine the features of the geographical position of the Pacific Ocean.

2) Make an assumption about the nature of the ocean.

Geographical position of the Pacific Ocean
Performance plan	Features of the geographical location
Area, million km2
position relative to the equator, prime meridian, continents and other oceans	Located in all four hemispheres of the Earth. The equator divides the Pacific Ocean into approximately two equal parts, the nature of which is similar. The widest part is located between the tropics. It extends from west to east for 19 thousand km (almost half of the earth's equator!), And from north to south - for 16 thousand km. Washes the shores of North and South America, Antarctica, Australia and Eurasia. The border with the Arctic Ocean passes through the Bering Strait. The borders with the Atlantic and Indian Oceans are drawn along conditional meridians
Coastline features: seas, bays, straits, islands	The coastline of North and South America is relatively even, and strongly indented near the coast of Eurasia. There are many marginal seas here. There are a significant number of archipelagos and individual islands in the ocean. In the north and west they form island arcs. The largest cluster of islands in the world - Oceania - is concentrated in the central and eastern parts of the ocean

Conclusion 1. The position of the ocean in almost all geographic zones of the Earth, with the exception of the northernmost one, predetermines the extraordinary diversity of its nature.

3. Bottom relief

Working with a physical map of the Pacific Ocean, the map "The structure of the bottom of the Pacific Ocean"

Tasks. Compare the maps and identify patterns in the placement of the main landforms of the bottom of the Pacific Ocean.

A significant part of the Pacific Ocean lies on one lithospheric plate, which interacts with other plates. The zones of their interaction are adjacent to deep-sea trenches (the deepest one is Mariana, 11022 m) and island arcs. Connected to the system of deep-sea trenches and mountain structures on the continents and islands that surround the ocean is an almost continuous chain of active volcanoes that form the Pacific Ring of Fire. In this zone, terrestrial and underwater earthquakes often occur, causing tsunamis.

The relief of the bottom of the Pacific Ocean is complex. The continental shelf in the ocean is about 10% of its total area, it is largest in the western part, the continental slope is steep, dissected by canyons. The ocean floor makes up more than 65% of the bottom area. It is crossed by numerous underwater mountain ranges (Skhidnotikhookansk, Pivdennotikhookansk uplifts), which distribute the bed into several basins (the North-Eastern one). At the bottom of the basins there are many mountains of volcanic origin.

Conclusion 2. The relief of the bottom of the Pacific Ocean is complex: at the bottom of the ocean there are large basins separated by oceanic uplifts. A characteristic feature is extremely intense seismic phenomena and volcanism.

4. Climate and water

Working with thematic maps

Tasks

1) Using a climatic map and a map of climatic zones, establish air temperature indicators, types of atmospheric circulation, climatic zones in which the Pacific Ocean is located.

2) Using the maps "Water temperature" and "Water salinity", set the temperature and salinity indicators of the surface waters of the Pacific Ocean. Explain the reasons for the distribution of these indicators.

The overwhelming part of the Pacific Ocean lies in the equatorial, subequatorial and tropical zones. The air temperature in these areas ranges from +16 °С to +24 °С. In the north of the ocean in winter, it drops below 0 ° C, and near the coast of Antarctica, negative temperatures will outweigh almost a whole year. Trade winds dominate the ocean in tropical latitudes, westerly winds dominate in temperate latitudes, and monsoons form off the coast of Eurasia.

In temperate latitudes, storms often occur, caused by strong westerly winds.

The location of the Pacific Ocean in almost all climatic zones of the Earth is the reason for the formation of all types of surface water masses, except for the Arctic ones. Due to the large area of ​​the ocean between the tropics, the average temperatures of its surface waters are higher than in other oceans (+19.1 °C). The salinity of surface waters ranges from 30 to 35 ‰. There is little floating ice in the north of the Pacific Ocean, in contrast to the southern part, where icebergs form near the coast of Antarctica.

The flow systems form two rings. Northern: Northern Tradewind, Kuroshio, North Pacific, California; South - South Tradewind, East Australian, Peruvian, for the West Winds.

Conclusion 3. The vast size of the Pacific Ocean has caused significant differences in its climate. This led to the presence in it of almost all types of water masses. The indicators of temperature and salinity of surface waters have a predominantly zonal distribution.

V. CONSOLIDATION OF THE STUDYED MATERIAL

Practical work 12

Tasks. Designate on the contour map of the sea: Bering, Okhotsk, Japanese, Yellow,< Східнокитайське, Южнокитайская, Филиппинское, Коралловое, Фиджи, Тасманово; заливы: Аляска, Калифорнийский; острова: Алеутские, Курильские, Японские, Филиппинские, Новая Гвинея, Новая Зеландия, Гавайские, Соломоновы, Тонга; полуострова: Аляска, Камчатка, Калифорния; желоба: Марианский, Алеутський, Чілійський; котловины: Восточная, Южная.

VI. SUMMARY OF THE LESSON, REFLECTION

The teacher reminds students of their assumptions about the uniqueness of the Pacific Ocean. Can you add more evidence to the list?

VII. HOMEWORK

1. Work out the corresponding paragraph of the textbook.

2. Leading (to individual students): write a message about environmental problems Pacific Ocean, coastal and water protected areas.