Preliminary information:
Total Area:
It extends from the Arctic in the north to Antarctica in the south, bounded by Asia and Australia in the west, and the Americas in the east. At 169.2 million square kilometres (65.3 million square miles) in area, this largest division of the World Ocean – and, in turn, the hydrosphere – covers about 46% of the Earth's water surface and about 32% of its total surface area, making it larger than all of the Earth's land area combined.
Area comparative:
bout 15 times the size of the US; covers about 28% of the global surface; larger than the total land area of the world.
Coastline: 135,663 km
Geographic coordinates: 0 00 N, 160 00 W
Depth:
The lowest point on earth—the Mariana Trench—lies 10,911 metres (35,797 ft) below sea level. Its average depth is 4,280 metres (14,000 ft). Because of the depth of the Pacific Ocean, tsunamis (huge waves created by earthquakes) can reach speeds of 750 kilometers an hour, the same velocity as a jet airplane.
Prelude:
The Pacific Ocean is the largest of the Earth's oceanic divisions. Its name is derived from the Latin name Mare Pacificum, "peaceful sea", bestowed upon it by the Portuguese explorer Ferdinand Magellan. It extends from the Arctic in the north to Antarctica in the south, bounded by Asia and Australia in the west, and the Americas in the east. At 169.2 million square kilometres (65.3 million square miles) in area, this largest division of the World Ocean – and, in turn, the hydrosphere – covers about 46% of the Earth's water surface and about 32% of its total surface area, making it larger than all of the Earth's land area combined. The equator subdivides it into the North Pacific Ocean and South Pacific Ocean, with two exceptions: the Galápagos and Gilbert Islands are deemed wholly within the South Pacific. The Mariana Trench in the western North Pacific is the deepest point in the Pacific and in the world, reaching a depth of 10,911 metres (35,798 ft).
The ocean encompasses almost a third of the Earth's surface, having an area of 179.7 million square kilometres (69.4 million sq mi and 161 million cubic mi) significantly larger than Earth's entire landmass, with room for another Africa to spare. Extending approximately 15,500 kilometres (9,600 mi) from the Bering Sea in the Arctic to the icy margins of Antarctica's Ross Sea in the south (although the Antarctic regions of the Pacific are sometimes described as part of the circumpolar Southern Ocean), the Pacific reaches its greatest east-west width at about 5°N latitude, where it stretches approximately 19,800 kilometres (12,300 mi) from Indonesia to the coast of Colombia and Peru - halfway across the world, and more than five times the diameter of the Moon. The western limit of the ocean is often placed at the Strait of Malacca. The lowest point on earth—the Mariana Trench—lies 10,911 metres (35,797 ft) below sea level. Its average depth is 4,280 metres (14,000 ft).
The Pacific contains about 25,000 islands (more than the total number in the rest of the world's oceans combined), the majority of which are found south of the equator. Including partially submerged islands, the figure is substantially higher.
The Pacific Ocean is currently shrinking from plate tectonics, while the Atlantic Ocean is increasing in size, by roughly an inch per year (2-3 cm/yr) on 3 sides, roughly averaging 0.2 square miles (0.5 km2) a year.
Along the Pacific Ocean's irregular western margins lie many seas, the largest of which are the Celebes Sea, Coral Sea, East China Sea, Philippine Sea, Sea of Japan, South China Sea, Sulu Sea, Tasman Sea, and Yellow Sea. The Strait of Malacca joins the Pacific and the Indian Oceans on the west, and Drake Passage and the Straits of Magellan link the Pacific with the Atlantic Ocean on the east. To the north, the Bering Strait connects the Pacific with the Arctic Ocean.
As the Pacific straddles the ± 180° meridian, the West Pacific (or western Pacific, near Asia) is in the Eastern Hemisphere, while the East Pacific (or eastern Pacific, near the Americas) is in the Western Hemisphere.
For most of Magellan's voyage from the Strait of Magellan to the Philippines, the explorer indeed found the ocean peaceful. However, the Pacific is not always peaceful. Many tropical cyclones (typhoons, the equivalent of Atlantic hurricanes), batter the islands of the Pacific. The lands around the Pacific rim are full of volcanoes and often affected by earthquakes. Tsunamis, caused by underwater earthquakes, have devastated many islands and destroyed entire towns.
Geology:
The andesite line is the most significant regional distinction in the Pacific. It separates the deeper, mafic igneous rock of the Central Pacific Basin from the partially submerged continental areas of felsic igneous rock on its margins. The andesite line follows the western edge of the islands off California and passes south of the Aleutian arc, along the eastern edge of the Kamchatka Peninsula, the Kuril Islands, Japan, the Mariana Islands, the Solomon Islands, and New Zealand's North Island. The dissimilarity continues northeastward along the western edge of the Andes Cordillera along South America to Mexico, returning then to the islands off California. Indonesia, the Philippines, Japan, New Guinea, and New Zealand—all eastward extensions of the continental blocks of Asia, Australia and Zealandia—lie outside the Andesite Line.
Within the closed loop of the Andesite Line are most of the deep troughs, submerged volcanic mountains, and oceanic volcanic islands that characterize the Pacific basin. Here basaltic lavas gently flow out of rifts to build huge dome-shaped volcanic mountains whose eroded summits form island arcs, chains, and clusters. Outside the Andesite Line, volcanism is of the explosive type, and the Pacific Ring of Fire is the world's foremost belt of explosive volcanism. The Ring of Fire is named after the several hundred active volcanoes that sit above the various subduction zones.
The Pacific Ocean is the only ocean which is almost totally bounded by subduction zones. Only the Antarctic and Australian coasts have no nearby subduction zones.
Bottom Terrain:
The ocean floor in the eastern Pacific is dominated by the East Pacific Rise, which is a part of the worldwide Mid-Ocean Ridge system. About 3,000 km (1,800 mi) across, the rise stands about 3 km (2 mi) above the adjacent ocean floor. The western part of the Pacific Ocean floor consists of mountain arcs that rise above the sea as island groups, such as the Solomon Islands and New Zealand, and deep trenches, such as the Mariana Trench, the Philippine Trench, and the Tonga Trench. Most of the deep trenches lie adjacent to the outer margins of the wide western Pacific continental shelf.
Total Area:
It extends from the Arctic in the north to Antarctica in the south, bounded by Asia and Australia in the west, and the Americas in the east. At 169.2 million square kilometres (65.3 million square miles) in area, this largest division of the World Ocean – and, in turn, the hydrosphere – covers about 46% of the Earth's water surface and about 32% of its total surface area, making it larger than all of the Earth's land area combined.
Area comparative:
bout 15 times the size of the US; covers about 28% of the global surface; larger than the total land area of the world.
Coastline: 135,663 km
Geographic coordinates: 0 00 N, 160 00 W
Depth:
The lowest point on earth—the Mariana Trench—lies 10,911 metres (35,797 ft) below sea level. Its average depth is 4,280 metres (14,000 ft). Because of the depth of the Pacific Ocean, tsunamis (huge waves created by earthquakes) can reach speeds of 750 kilometers an hour, the same velocity as a jet airplane.
Prelude:
The Pacific Ocean is the largest of the Earth's oceanic divisions. Its name is derived from the Latin name Mare Pacificum, "peaceful sea", bestowed upon it by the Portuguese explorer Ferdinand Magellan. It extends from the Arctic in the north to Antarctica in the south, bounded by Asia and Australia in the west, and the Americas in the east. At 169.2 million square kilometres (65.3 million square miles) in area, this largest division of the World Ocean – and, in turn, the hydrosphere – covers about 46% of the Earth's water surface and about 32% of its total surface area, making it larger than all of the Earth's land area combined. The equator subdivides it into the North Pacific Ocean and South Pacific Ocean, with two exceptions: the Galápagos and Gilbert Islands are deemed wholly within the South Pacific. The Mariana Trench in the western North Pacific is the deepest point in the Pacific and in the world, reaching a depth of 10,911 metres (35,798 ft).
The ocean encompasses almost a third of the Earth's surface, having an area of 179.7 million square kilometres (69.4 million sq mi and 161 million cubic mi) significantly larger than Earth's entire landmass, with room for another Africa to spare. Extending approximately 15,500 kilometres (9,600 mi) from the Bering Sea in the Arctic to the icy margins of Antarctica's Ross Sea in the south (although the Antarctic regions of the Pacific are sometimes described as part of the circumpolar Southern Ocean), the Pacific reaches its greatest east-west width at about 5°N latitude, where it stretches approximately 19,800 kilometres (12,300 mi) from Indonesia to the coast of Colombia and Peru - halfway across the world, and more than five times the diameter of the Moon. The western limit of the ocean is often placed at the Strait of Malacca. The lowest point on earth—the Mariana Trench—lies 10,911 metres (35,797 ft) below sea level. Its average depth is 4,280 metres (14,000 ft).
The Pacific contains about 25,000 islands (more than the total number in the rest of the world's oceans combined), the majority of which are found south of the equator. Including partially submerged islands, the figure is substantially higher.
The Pacific Ocean is currently shrinking from plate tectonics, while the Atlantic Ocean is increasing in size, by roughly an inch per year (2-3 cm/yr) on 3 sides, roughly averaging 0.2 square miles (0.5 km2) a year.
Along the Pacific Ocean's irregular western margins lie many seas, the largest of which are the Celebes Sea, Coral Sea, East China Sea, Philippine Sea, Sea of Japan, South China Sea, Sulu Sea, Tasman Sea, and Yellow Sea. The Strait of Malacca joins the Pacific and the Indian Oceans on the west, and Drake Passage and the Straits of Magellan link the Pacific with the Atlantic Ocean on the east. To the north, the Bering Strait connects the Pacific with the Arctic Ocean.
As the Pacific straddles the ± 180° meridian, the West Pacific (or western Pacific, near Asia) is in the Eastern Hemisphere, while the East Pacific (or eastern Pacific, near the Americas) is in the Western Hemisphere.
For most of Magellan's voyage from the Strait of Magellan to the Philippines, the explorer indeed found the ocean peaceful. However, the Pacific is not always peaceful. Many tropical cyclones (typhoons, the equivalent of Atlantic hurricanes), batter the islands of the Pacific. The lands around the Pacific rim are full of volcanoes and often affected by earthquakes. Tsunamis, caused by underwater earthquakes, have devastated many islands and destroyed entire towns.
Geology:
The andesite line is the most significant regional distinction in the Pacific. It separates the deeper, mafic igneous rock of the Central Pacific Basin from the partially submerged continental areas of felsic igneous rock on its margins. The andesite line follows the western edge of the islands off California and passes south of the Aleutian arc, along the eastern edge of the Kamchatka Peninsula, the Kuril Islands, Japan, the Mariana Islands, the Solomon Islands, and New Zealand's North Island. The dissimilarity continues northeastward along the western edge of the Andes Cordillera along South America to Mexico, returning then to the islands off California. Indonesia, the Philippines, Japan, New Guinea, and New Zealand—all eastward extensions of the continental blocks of Asia, Australia and Zealandia—lie outside the Andesite Line.
Within the closed loop of the Andesite Line are most of the deep troughs, submerged volcanic mountains, and oceanic volcanic islands that characterize the Pacific basin. Here basaltic lavas gently flow out of rifts to build huge dome-shaped volcanic mountains whose eroded summits form island arcs, chains, and clusters. Outside the Andesite Line, volcanism is of the explosive type, and the Pacific Ring of Fire is the world's foremost belt of explosive volcanism. The Ring of Fire is named after the several hundred active volcanoes that sit above the various subduction zones.
The Pacific Ocean is the only ocean which is almost totally bounded by subduction zones. Only the Antarctic and Australian coasts have no nearby subduction zones.
Bottom Terrain:
The ocean floor in the eastern Pacific is dominated by the East Pacific Rise, which is a part of the worldwide Mid-Ocean Ridge system. About 3,000 km (1,800 mi) across, the rise stands about 3 km (2 mi) above the adjacent ocean floor. The western part of the Pacific Ocean floor consists of mountain arcs that rise above the sea as island groups, such as the Solomon Islands and New Zealand, and deep trenches, such as the Mariana Trench, the Philippine Trench, and the Tonga Trench. Most of the deep trenches lie adjacent to the outer margins of the wide western Pacific continental shelf.
Natural hazards:
surrounded by a zone of violent volcanic and earthquake activity sometimes referred to as the "Pacific Ring of Fire"; subject to tropical cyclones (typhoons) in southeast and east Asia from May to December (most frequent from July to October); tropical cyclones (hurricanes) may form south of Mexico and strike Central America and Mexico from June to October (most common in August and September); cyclical El Nino/La Nina phenomenon occurs in the equatorial Pacific, influencing weather in the Western Hemisphere and the western Pacific; ships subject to superstructure icing in extreme north from October to May; persistent fog in the northern Pacific can be a maritime hazard from June to December.
Seamount chains:
The Pacific Ocean contains several long seamount chains, formed by hotspot volcanism. These include the Emperor Seamounts chain and the Louisville seamount chain.
Landmasses:
The largest landmass entirely within the Pacific Ocean is the island of New Guinea— the second largest island in the world. Almost all of the smaller islands of the Pacific lie between 30°N and 30°S, extending from Southeast Asia to Easter Island; the rest of the Pacific Basin is almost entirely submerged. During the Last glacial period, New Guinea was part of Australia so the largest landmass would have been Borneo-Palawan.
The great triangle of Polynesia, connecting Hawaii, Easter Island, and New Zealand, encompasses the island arcs and clusters of the Cook Islands, Marquesas Islands, Samoa, Society, Tokelau, Tonga, Tuamotu, Tuvalu and the Wallis and Futuna islands.
North of the equator and west of the International Date Line are the numerous small islands of Micronesia, including the Caroline Islands, the Marshall Islands and the Mariana Islands.
In the southwestern corner of the Pacific lie the islands of Melanesia, dominated by New Guinea. Other important island groups of Melanesia include the Bismarck Archipelago, Fiji, New Caledonia, the Solomon Islands and Vanuatu.
Islands in the Pacific Ocean are of four basic types: continental islands, high islands, coral reefs, and uplifted coral platforms. Continental islands lie outside the Andesite line and include New Guinea, the islands of New Zealand, and the Philippines. These islands are structurally associated with nearby continents. High islands are of volcanic origin, and many contain active volcanoes. Among these are Bougainville, Hawaii, and the Solomon Islands.
The third and fourth types of islands are both the result of coralline island building. Coral reefs are low-lying structures that have built up on basaltic lava flows under the ocean's surface. One of the most dramatic is the Great Barrier Reef off northeastern Australia. A second island type formed of coral is the uplifted coral platform, which is usually slightly larger than the low coral islands. Examples include Banaba (formerly Ocean Island) and Makatea in the Tuamotu group of French Polynesia.
Climate:
planetary air pressure systems and resultant wind patterns exhibit remarkable uniformity in the south and east; trade winds and westerly winds are well-developed patterns, modified by seasonal fluctuations; tropical cyclones (hurricanes) may form south of Mexico from June to October and affect Mexico and Central America; continental influences cause climatic uniformity to be much less pronounced in the eastern and western regions at the same latitude in the North Pacific Ocean; the western Pacific is monsoonal - a rainy season occurs during the summer months, when moisture-laden winds blow from the ocean over the land, and a dry season during the winter months, when dry winds blow from the Asian landmass back to the ocean; tropical cyclones (typhoons) may strike southeast and east Asia from May to December.
The ocean and the atmosphere are closely linked — a fact that is clearly demonstrated by the global weather phenomena we know as "El Niño" and "La Niña," which arise in the Pacific Ocean.
Ages ago, Peruvian fishermen named the seasonal warming of the waters off their coast, which occurs in December, "El Nino," which is Spanish for "the Christ child." During a normal year, the waters off South America are typically cold and highly productive for fishing. Then in December (which is summer in the Southern Hemisphere), the water normally warms and fishing becomes less productive. Cold water usually returns again in June, when the fishing season begins again there. In some years, however, the water stays warm throughout the year and can cause dramatic weather around the world. The term "El Niño" is now used to refer to this climatic process.
Steady, westward-blowing trade winds cause warm water to pile up in the western Pacific. During El Niño, the trade winds weaken and cannot "contain" this huge pool of warm water. Consequently, warm water extends far eastward. In the United States, the effects of an El Niño winter include warmer than normal temperatures from the Great Lakes to Alaska, wetter than normal conditions across the southern tier of states, some dryness in the Midwest, and cooler than normal temperatures in the Southeast. It can also include a decrease in hurricanes that reach land.
In some ways, La Niña is the opposite of El Niño and is characterized by cooler than normal ocean water surface temperatures in the central tropical Pacific. In the United States, a La Niña winter includes temperatures that are cooler than normal over the Northwest, warmer than normal over the Southeast, drier than normal from Florida to Arizona, and wetter than normal over the Pacific Northwest and parts of the Midwest. La Niña may also bring an increase in hurricanes that reach land in the United States.
According to the NOAA National Weather Service's Climate Prediction Center, it's likely that El Niño conditions will persist through early 2005. Among the expected impacts around the globe are drier-than-average conditions in Indonesia (through early 2005), northern and northeastern Australia (Nov. 2004 – Feb. 2005), and southeastern Africa (Nov. 2004–March 2005). If the warming in the tropic Pacific strengthens and spreads eastward to the South American coast, then wetter-than-average conditions would be expected in coastal sections of Ecuador and northern Peru during the first few months of 2005, and drier-than-average conditions would be expected to develop in the eastern Amazon late this year and spread to northeast Brazil during Feb.–April 2005.
Terrain:
surface currents in the northern Pacific are dominated by a clockwise, warm-water gyre (broad circular system of currents) and in the southern Pacific by a counterclockwise, cool-water gyre; in the northern Pacific, sea ice forms in the Bering Sea and Sea of Okhotsk in winter; in the southern Pacific, sea ice from Antarctica reaches its northernmost extent in October; the ocean floor in the eastern Pacific is dominated by the East Pacific Rise, while the western Pacific is dissected by deep trenches, including the Mariana Trench, which is the world's deepest
Water characteristics:
Water temperatures in the Pacific vary from freezing in the poleward areas to about 30 °C (86 °F) near the equator. Salinity also varies latitudinally. The water near the equator is less salty than that found in the mid-latitudes because of abundant equatorial precipitation throughout the year. Poleward of the temperate latitudes salinity is also low, because little evaporation of seawater takes place in these frigid areas.
The motion of Pacific waters is generally clockwise in the Northern Hemisphere (the North Pacific gyre) and counter-clockwise in the Southern Hemisphere. The North Equatorial Current, driven westward along latitude 15°N by the trade winds, turns north near the Philippines to become the warm Japan or Kuroshio Current.
Turning eastward at about 45°N, the Kuroshio forks and some waters move northward as the Aleutian Current, while the rest turn southward to rejoin the North Equatorial Current. The Aleutian Current branches as it approaches North America and forms the base of a counter-clockwise circulation in the Bering Sea. Its southern arm becomes the chilled slow, south-flowing California Current.
The South Equatorial Current, flowing west along the equator, swings southward east of New Guinea, turns east at about 50°S, and joins the main westerly circulation of the Southern Pacific, which includes the Earth-circling Antarctic Circumpolar Current. As it approaches the Chilean coast, the South Equatorial Current divides; one branch flows around Cape Horn and the other turns north to form the Peru or Humboldt Current.
Natural resources:
oil and gas fields, polymetallic nodules, sand and gravel aggregates, placer deposits, fish.
One of the Pacific Ocean’s greatest assets is fish, including herring, salmon, sardines, snapper, swordfish, tuna, and shellfish. In 1996, over half (60%) of the world’s total fish catch came from the Pacific Ocean. Pearls are harvested along Australia, Japan, Papua New Guinea, Nicaragua, Panama, and the Philippines. Exploitation of offshore oil and gas reserves is playing an ever-increasing role in the energy supplies of Australia, New Zealand, China, the United States, and Peru.
Environment:
surrounded by a zone of violent volcanic and earthquake activity sometimes referred to as the "Pacific Ring of Fire"; subject to tropical cyclones (typhoons) in southeast and east Asia from May to December (most frequent from July to October); tropical cyclones (hurricanes) may form south of Mexico and strike Central America and Mexico from June to October (most common in August and September); cyclical El Nino/La Nina phenomenon occurs in the equatorial Pacific, influencing weather in the Western Hemisphere and the western Pacific; ships subject to superstructure icing in extreme north from October to May; persistent fog in the northern Pacific can be a maritime hazard from June to December.
Seamount chains:
The Pacific Ocean contains several long seamount chains, formed by hotspot volcanism. These include the Emperor Seamounts chain and the Louisville seamount chain.
Landmasses:
The largest landmass entirely within the Pacific Ocean is the island of New Guinea— the second largest island in the world. Almost all of the smaller islands of the Pacific lie between 30°N and 30°S, extending from Southeast Asia to Easter Island; the rest of the Pacific Basin is almost entirely submerged. During the Last glacial period, New Guinea was part of Australia so the largest landmass would have been Borneo-Palawan.
The great triangle of Polynesia, connecting Hawaii, Easter Island, and New Zealand, encompasses the island arcs and clusters of the Cook Islands, Marquesas Islands, Samoa, Society, Tokelau, Tonga, Tuamotu, Tuvalu and the Wallis and Futuna islands.
North of the equator and west of the International Date Line are the numerous small islands of Micronesia, including the Caroline Islands, the Marshall Islands and the Mariana Islands.
In the southwestern corner of the Pacific lie the islands of Melanesia, dominated by New Guinea. Other important island groups of Melanesia include the Bismarck Archipelago, Fiji, New Caledonia, the Solomon Islands and Vanuatu.
Islands in the Pacific Ocean are of four basic types: continental islands, high islands, coral reefs, and uplifted coral platforms. Continental islands lie outside the Andesite line and include New Guinea, the islands of New Zealand, and the Philippines. These islands are structurally associated with nearby continents. High islands are of volcanic origin, and many contain active volcanoes. Among these are Bougainville, Hawaii, and the Solomon Islands.
The third and fourth types of islands are both the result of coralline island building. Coral reefs are low-lying structures that have built up on basaltic lava flows under the ocean's surface. One of the most dramatic is the Great Barrier Reef off northeastern Australia. A second island type formed of coral is the uplifted coral platform, which is usually slightly larger than the low coral islands. Examples include Banaba (formerly Ocean Island) and Makatea in the Tuamotu group of French Polynesia.
Climate:
planetary air pressure systems and resultant wind patterns exhibit remarkable uniformity in the south and east; trade winds and westerly winds are well-developed patterns, modified by seasonal fluctuations; tropical cyclones (hurricanes) may form south of Mexico from June to October and affect Mexico and Central America; continental influences cause climatic uniformity to be much less pronounced in the eastern and western regions at the same latitude in the North Pacific Ocean; the western Pacific is monsoonal - a rainy season occurs during the summer months, when moisture-laden winds blow from the ocean over the land, and a dry season during the winter months, when dry winds blow from the Asian landmass back to the ocean; tropical cyclones (typhoons) may strike southeast and east Asia from May to December.
The ocean and the atmosphere are closely linked — a fact that is clearly demonstrated by the global weather phenomena we know as "El Niño" and "La Niña," which arise in the Pacific Ocean.
Ages ago, Peruvian fishermen named the seasonal warming of the waters off their coast, which occurs in December, "El Nino," which is Spanish for "the Christ child." During a normal year, the waters off South America are typically cold and highly productive for fishing. Then in December (which is summer in the Southern Hemisphere), the water normally warms and fishing becomes less productive. Cold water usually returns again in June, when the fishing season begins again there. In some years, however, the water stays warm throughout the year and can cause dramatic weather around the world. The term "El Niño" is now used to refer to this climatic process.
Steady, westward-blowing trade winds cause warm water to pile up in the western Pacific. During El Niño, the trade winds weaken and cannot "contain" this huge pool of warm water. Consequently, warm water extends far eastward. In the United States, the effects of an El Niño winter include warmer than normal temperatures from the Great Lakes to Alaska, wetter than normal conditions across the southern tier of states, some dryness in the Midwest, and cooler than normal temperatures in the Southeast. It can also include a decrease in hurricanes that reach land.
In some ways, La Niña is the opposite of El Niño and is characterized by cooler than normal ocean water surface temperatures in the central tropical Pacific. In the United States, a La Niña winter includes temperatures that are cooler than normal over the Northwest, warmer than normal over the Southeast, drier than normal from Florida to Arizona, and wetter than normal over the Pacific Northwest and parts of the Midwest. La Niña may also bring an increase in hurricanes that reach land in the United States.
According to the NOAA National Weather Service's Climate Prediction Center, it's likely that El Niño conditions will persist through early 2005. Among the expected impacts around the globe are drier-than-average conditions in Indonesia (through early 2005), northern and northeastern Australia (Nov. 2004 – Feb. 2005), and southeastern Africa (Nov. 2004–March 2005). If the warming in the tropic Pacific strengthens and spreads eastward to the South American coast, then wetter-than-average conditions would be expected in coastal sections of Ecuador and northern Peru during the first few months of 2005, and drier-than-average conditions would be expected to develop in the eastern Amazon late this year and spread to northeast Brazil during Feb.–April 2005.
Terrain:
surface currents in the northern Pacific are dominated by a clockwise, warm-water gyre (broad circular system of currents) and in the southern Pacific by a counterclockwise, cool-water gyre; in the northern Pacific, sea ice forms in the Bering Sea and Sea of Okhotsk in winter; in the southern Pacific, sea ice from Antarctica reaches its northernmost extent in October; the ocean floor in the eastern Pacific is dominated by the East Pacific Rise, while the western Pacific is dissected by deep trenches, including the Mariana Trench, which is the world's deepest
Water characteristics:
Water temperatures in the Pacific vary from freezing in the poleward areas to about 30 °C (86 °F) near the equator. Salinity also varies latitudinally. The water near the equator is less salty than that found in the mid-latitudes because of abundant equatorial precipitation throughout the year. Poleward of the temperate latitudes salinity is also low, because little evaporation of seawater takes place in these frigid areas.
The motion of Pacific waters is generally clockwise in the Northern Hemisphere (the North Pacific gyre) and counter-clockwise in the Southern Hemisphere. The North Equatorial Current, driven westward along latitude 15°N by the trade winds, turns north near the Philippines to become the warm Japan or Kuroshio Current.
Turning eastward at about 45°N, the Kuroshio forks and some waters move northward as the Aleutian Current, while the rest turn southward to rejoin the North Equatorial Current. The Aleutian Current branches as it approaches North America and forms the base of a counter-clockwise circulation in the Bering Sea. Its southern arm becomes the chilled slow, south-flowing California Current.
The South Equatorial Current, flowing west along the equator, swings southward east of New Guinea, turns east at about 50°S, and joins the main westerly circulation of the Southern Pacific, which includes the Earth-circling Antarctic Circumpolar Current. As it approaches the Chilean coast, the South Equatorial Current divides; one branch flows around Cape Horn and the other turns north to form the Peru or Humboldt Current.
Natural resources:
oil and gas fields, polymetallic nodules, sand and gravel aggregates, placer deposits, fish.
One of the Pacific Ocean’s greatest assets is fish, including herring, salmon, sardines, snapper, swordfish, tuna, and shellfish. In 1996, over half (60%) of the world’s total fish catch came from the Pacific Ocean. Pearls are harvested along Australia, Japan, Papua New Guinea, Nicaragua, Panama, and the Philippines. Exploitation of offshore oil and gas reserves is playing an ever-increasing role in the energy supplies of Australia, New Zealand, China, the United States, and Peru.
Environment:
The Pacific Ocean’s endangered marine species include the dugong, sea lion, sea otter, seals, turtles, and whales. Current major environmental issues include oil pollution in the Philippine Sea and South China Sea. In terms of natural hazards, the Pacific Ocean is surrounded by a zone of violent volcanic and earthquake activity (“The Ring of Fire”). Hurricanes may form south of Mexico and strike Central America and Mexico from June to October. The greatest typhoon frequency exists within the triangle from southern Japan to the central Philippines to eastern Micronesia.
Marine pollution: Marine pollution is a generic term for the harmful entry into the ocean of chemicals or particles. The biggest culprit are rivers that empty into the Ocean, and with it the many chemicals used as fertilizers in agriculture as well as waste from livestock and humans. The excess of oxygen depleting chemicals in the water leads to hypoxia and the creation of a dead zone.
Marine debris, also known as marine litter, is a term used to describe human-created waste that has found itself floating in a lake, sea, ocean or waterway. Oceanic debris tends to accumulate at the centre of gyres and coastlines, frequently washing aground where it is known as beach litter.
History and economy:
Important human migrations occurred in the Pacific in prehistoric times, most notably those of the Polynesians from the Asian edge of the ocean to Tahiti and then to Hawaii, New Zealand, and Easter Island.
The ocean was first sighted by Europeans early in the 16th century, first by the Spanish explorer Vasco Núñez de Balboa who crossed the Isthmus of Panama in 1513, and then by Ferdinand Magellan, who sailed the Pacific during his circumnavigation from 1519 to 1522.
A native of Portugal, Magellan renounced his loyalty to that nation after King Emanuel rejected Magellan’s petition for a post within the royal navy. Magellan then left for Spain, which agreed to support Magellan’s claim of a western route to the Spice Islands through a seaway near the southern tip of South America.
On September 20, 1519, Magellan and a crew of 270 men set sail from Spain on their around-the-world voyage in five small vessels including his flagship Trinidad, Concepcion, San Antonio, Victoria, and Santiago. It took the fleet, or at least the three remaining ships in the fleet, 38 days to navigate the strait around South America that was to bear Magellan’s name. During the last week of November, the fleet emerged into what Magellan described as a “beautiful, peaceful ocean.” Thus, it was named the Pacific Ocean (“pacific” meaning “peaceful.”)
Upon entering the Pacific Ocean, Magellan mistakenly thought the Spice Islands were only a short voyage away. Nearly four months later, in March 1521, he and his crew finally reached what is known today as the Philippines. A few weeks later, he was fatally wounded after becoming involved in a dispute between warring Philippine tribes. Only one ship, Victoria, and 18 of Magellan’s original crew members returned to Spain, thereby completing the first circumnavigation of the globe. Although Magellan’s route proved impractical for the spice trade, his voyage has been called the greatest single human achievement on the seas.
In 1564, conquistadors crossed the ocean from Mexico led by Miguel López de Legazpi who sailed to the Philippines and Mariana Islands. For the remainder of the 16th century, Spanish influence was paramount, with ships sailing from Spain to the Philippines, New Guinea, and the Solomon Islands.
During the 17th century, the Dutch, sailing around southern Africa, dominated discovery and trade; Abel Janszoon Tasman discovered Tasmania and New Zealand in 1642. The 18th century marked a burst of exploration by the Russians in Alaska and the Aleutian Islands, the French in Polynesia, and the British in the three voyages of James Cook to the South Pacific and Australia, Hawaii, and the North American Pacific Northwest.
Growing imperialism during the 19th century resulted in the occupation of much of Oceania by European powers, and later, the United States and Japan. Significant contributions to oceanographic knowledge were made by the voyages of HMS Beagle in the 1830s, with Charles Darwin aboard; HMS Challenger during the 1870s; the USS Tuscarora (1873-76); and the German Gazelle (1874-76). Although the United States gained control of the Philippines from Spain in 1898, Japan controlled most of the western Pacific by 1914 and occupied many other islands during World War II. However, by the end of that war, Japan was defeated and the U.S. Pacific Fleet was the virtual master of the ocean. Since the end of World War II, many former colonies in the Pacific have become independent states.
The exploitation of the Pacific's mineral wealth is hampered by the ocean's great depths. In shallow waters of the continental shelves off the coasts of Australia and New Zealand, petroleum and natural gas are extracted, and pearls are harvested along the coasts of Australia, Japan, Papua New Guinea, Nicaragua, Panama, and the Philippines, although in sharply declining volume in some cases. The Pacific's greatest asset is its fish. The shoreline waters of the continents and the more temperate islands yield herring, salmon, sardines, snapper, swordfish, and tuna, as well as shellfish.
Economy – overview: The Pacific Ocean is a major contributor to the world economy and particularly to those nations its waters directly touch. It provides low-cost sea transportation between East and West, extensive fishing grounds, offshore oil and gas fields, minerals, and sand and gravel for the construction industry. In 1996, over 60% of the world's fish catch came from the Pacific Ocean. Exploitation of offshore oil and gas reserves is playing an ever-increasing role in the energy supplies of the US, Australia, NZ, China, and Peru. The high cost of recovering offshore oil and gas, combined with the wide swings in world prices for oil since 1985, has led to fluctuations in new drillings.
Nations & Islands:
Seventeen independent nations are located in the Pacific: Australia, Fiji, Japan, Kiribati, Marshall Islands, Micronesia, Nauru, New Zealand, Palau, Papua New Guinea, the Philippines, Samoa, Solomon Islands, Taiwan, Tonga, Tuvalu, and Vanuatu. The U.S. state of Hawaii is also located here and several island territories and possessions of Australia, Chile, France, Japan, New Zealand, United Kingdom, and the United States.
The largest land mass in this ocean is the continent of Australia, which is about equal in size to the 48 contiguous states of the United States. There are some 25,000 islands in the Pacific Ocean — which is more than the rest of the world's oceans combined. Almost all the smaller islands lie between 30°N and 30°S latitude, extending from Southeast Asia to Easter Island. The rest of the Pacific Basin is almost devoid of land.
Bordering countries and territories :
American Samoa, Australia, Brunei, Cambodia, Canada, Chile, People's Republic of China, Colombia, Cook Islands, Costa Rica, East Timor, El Salvador, Ecuador, Fiji, French Polynesia, Guam, Guatemala, Honduras, Indonesia, Japan, Kiribati, North Korea, South Korea, Malaysia, Marshall Islands, Mexico, Federated States of Micronesia, Nauru, New Caledonia, New Zealand, Nicaragua, Niue, Northern Mariana Islands, Palau, Panama, Papua New Guinea, Peru, Philippines, Pitcairn Islands, Russia, Samoa, Singapore, Solomon Islands, Taiwan, Thailand, Tokelau, Tonga, Tuvalu, United States, Vanuatu, Vietnam, Wallis and Futuna.
Major ports and harbours:
Anchorage, Alaska, United States
Antofagasta, Chile
Arica, Chile
Auckland, New Zealand
Bacolod City, Philippines
Bangkok, Thailand
Batangas, Philippines
Bluff, New Zealand
Brisbane, Queensland, Australia
Buenaventura, Colombia
Busan, South Korea
Cabo San Lucas, Baja California Sur, Mexico
Cagayan de Oro City, Philippines
Callao, Peru
Cebu City, Philippines
Chongjin, North Korea
Dalian, People's Republic of China
Danang, Vietnam
Davao City, Philippines
Ensenada, Baja California, Mexico
Esmeraldas, Ecuador
Guayaquil, Ecuador
Haiphong, Vietnam
Hong Kong, People's Republic of China
Honolulu, Hawaii, United States
Incheon, South Korea
Iloilo, Philippines
Iquique, Chile
Jayapura, Indonesia
Kaohsiung, Republic of China (Taiwan)
Kitimat, British Columbia, Canada
Keelung, Republic of China (Taiwan)
Kobe, Japan
Kuala Terengganu, Malaysia
Laem Chabang, Thailand
Lyttelton, New Zealand
Long Beach, California, United States
Los Angeles, California, United States
Manta, Ecuador
Manzanillo, Colima, Mexico
Mazatlán, Sinaloa, Mexico
Melbourne, Victoria, Australia
Manila, Philippines
Nampho, North Korea
Newcastle, New South Wales, Australia
Oakland, California, United States
Panama City, Panama
Portland, Oregon, United States
Portoviejo, Ecuador
Prince Rupert, British Columbia, Canada
Puerto Chacabuco, Chile
Puerto Montt, Chile
Puerto Vallarta, Jalisco, Mexico
Qingdao, People's Republic of China
Saigon, Vietnam
San Antonio, Chile
San Diego, California, United States
San Francisco, California, United States
Seattle, Washington, United States
Shanghai, People's Republic of China
Shenzhen, People's Republic of China
Singapore
Songkhla, Thailand
Sydney, New South Wales, Australia
Tacoma, Washington, United States
Taichung, Republic of China (Taiwan)
Talcahuano, Chile
Tauranga, New Zealand
Tianjin, People's Republic of China
Tijuana, Baja California, Mexico
Tokyo, Japan
Valparaíso, Chile
Vancouver, British Columbia, Canada
Victoria, British Columbia, Canada
Vladivostok, Russia
Xiamen, People's Republic of China
Yantai, People's Republic of China
Yokohama, Japan
Zamboanga, Philippines
Resources:
http://en.wikipedia.org/wiki/Pacific_Ocean
http://www.ceoe.udel.edu/extreme2004/mission/divelocation/pacific.html
http://geography.about.com/library/cia/blcpacific.htm
Marine pollution: Marine pollution is a generic term for the harmful entry into the ocean of chemicals or particles. The biggest culprit are rivers that empty into the Ocean, and with it the many chemicals used as fertilizers in agriculture as well as waste from livestock and humans. The excess of oxygen depleting chemicals in the water leads to hypoxia and the creation of a dead zone.
Marine debris, also known as marine litter, is a term used to describe human-created waste that has found itself floating in a lake, sea, ocean or waterway. Oceanic debris tends to accumulate at the centre of gyres and coastlines, frequently washing aground where it is known as beach litter.
History and economy:
Important human migrations occurred in the Pacific in prehistoric times, most notably those of the Polynesians from the Asian edge of the ocean to Tahiti and then to Hawaii, New Zealand, and Easter Island.
The ocean was first sighted by Europeans early in the 16th century, first by the Spanish explorer Vasco Núñez de Balboa who crossed the Isthmus of Panama in 1513, and then by Ferdinand Magellan, who sailed the Pacific during his circumnavigation from 1519 to 1522.
A native of Portugal, Magellan renounced his loyalty to that nation after King Emanuel rejected Magellan’s petition for a post within the royal navy. Magellan then left for Spain, which agreed to support Magellan’s claim of a western route to the Spice Islands through a seaway near the southern tip of South America.
On September 20, 1519, Magellan and a crew of 270 men set sail from Spain on their around-the-world voyage in five small vessels including his flagship Trinidad, Concepcion, San Antonio, Victoria, and Santiago. It took the fleet, or at least the three remaining ships in the fleet, 38 days to navigate the strait around South America that was to bear Magellan’s name. During the last week of November, the fleet emerged into what Magellan described as a “beautiful, peaceful ocean.” Thus, it was named the Pacific Ocean (“pacific” meaning “peaceful.”)
Upon entering the Pacific Ocean, Magellan mistakenly thought the Spice Islands were only a short voyage away. Nearly four months later, in March 1521, he and his crew finally reached what is known today as the Philippines. A few weeks later, he was fatally wounded after becoming involved in a dispute between warring Philippine tribes. Only one ship, Victoria, and 18 of Magellan’s original crew members returned to Spain, thereby completing the first circumnavigation of the globe. Although Magellan’s route proved impractical for the spice trade, his voyage has been called the greatest single human achievement on the seas.
In 1564, conquistadors crossed the ocean from Mexico led by Miguel López de Legazpi who sailed to the Philippines and Mariana Islands. For the remainder of the 16th century, Spanish influence was paramount, with ships sailing from Spain to the Philippines, New Guinea, and the Solomon Islands.
During the 17th century, the Dutch, sailing around southern Africa, dominated discovery and trade; Abel Janszoon Tasman discovered Tasmania and New Zealand in 1642. The 18th century marked a burst of exploration by the Russians in Alaska and the Aleutian Islands, the French in Polynesia, and the British in the three voyages of James Cook to the South Pacific and Australia, Hawaii, and the North American Pacific Northwest.
Growing imperialism during the 19th century resulted in the occupation of much of Oceania by European powers, and later, the United States and Japan. Significant contributions to oceanographic knowledge were made by the voyages of HMS Beagle in the 1830s, with Charles Darwin aboard; HMS Challenger during the 1870s; the USS Tuscarora (1873-76); and the German Gazelle (1874-76). Although the United States gained control of the Philippines from Spain in 1898, Japan controlled most of the western Pacific by 1914 and occupied many other islands during World War II. However, by the end of that war, Japan was defeated and the U.S. Pacific Fleet was the virtual master of the ocean. Since the end of World War II, many former colonies in the Pacific have become independent states.
The exploitation of the Pacific's mineral wealth is hampered by the ocean's great depths. In shallow waters of the continental shelves off the coasts of Australia and New Zealand, petroleum and natural gas are extracted, and pearls are harvested along the coasts of Australia, Japan, Papua New Guinea, Nicaragua, Panama, and the Philippines, although in sharply declining volume in some cases. The Pacific's greatest asset is its fish. The shoreline waters of the continents and the more temperate islands yield herring, salmon, sardines, snapper, swordfish, and tuna, as well as shellfish.
Economy – overview: The Pacific Ocean is a major contributor to the world economy and particularly to those nations its waters directly touch. It provides low-cost sea transportation between East and West, extensive fishing grounds, offshore oil and gas fields, minerals, and sand and gravel for the construction industry. In 1996, over 60% of the world's fish catch came from the Pacific Ocean. Exploitation of offshore oil and gas reserves is playing an ever-increasing role in the energy supplies of the US, Australia, NZ, China, and Peru. The high cost of recovering offshore oil and gas, combined with the wide swings in world prices for oil since 1985, has led to fluctuations in new drillings.
Nations & Islands:
Seventeen independent nations are located in the Pacific: Australia, Fiji, Japan, Kiribati, Marshall Islands, Micronesia, Nauru, New Zealand, Palau, Papua New Guinea, the Philippines, Samoa, Solomon Islands, Taiwan, Tonga, Tuvalu, and Vanuatu. The U.S. state of Hawaii is also located here and several island territories and possessions of Australia, Chile, France, Japan, New Zealand, United Kingdom, and the United States.
The largest land mass in this ocean is the continent of Australia, which is about equal in size to the 48 contiguous states of the United States. There are some 25,000 islands in the Pacific Ocean — which is more than the rest of the world's oceans combined. Almost all the smaller islands lie between 30°N and 30°S latitude, extending from Southeast Asia to Easter Island. The rest of the Pacific Basin is almost devoid of land.
Bordering countries and territories :
American Samoa, Australia, Brunei, Cambodia, Canada, Chile, People's Republic of China, Colombia, Cook Islands, Costa Rica, East Timor, El Salvador, Ecuador, Fiji, French Polynesia, Guam, Guatemala, Honduras, Indonesia, Japan, Kiribati, North Korea, South Korea, Malaysia, Marshall Islands, Mexico, Federated States of Micronesia, Nauru, New Caledonia, New Zealand, Nicaragua, Niue, Northern Mariana Islands, Palau, Panama, Papua New Guinea, Peru, Philippines, Pitcairn Islands, Russia, Samoa, Singapore, Solomon Islands, Taiwan, Thailand, Tokelau, Tonga, Tuvalu, United States, Vanuatu, Vietnam, Wallis and Futuna.
Major ports and harbours:
Anchorage, Alaska, United States
Antofagasta, Chile
Arica, Chile
Auckland, New Zealand
Bacolod City, Philippines
Bangkok, Thailand
Batangas, Philippines
Bluff, New Zealand
Brisbane, Queensland, Australia
Buenaventura, Colombia
Busan, South Korea
Cabo San Lucas, Baja California Sur, Mexico
Cagayan de Oro City, Philippines
Callao, Peru
Cebu City, Philippines
Chongjin, North Korea
Dalian, People's Republic of China
Danang, Vietnam
Davao City, Philippines
Ensenada, Baja California, Mexico
Esmeraldas, Ecuador
Guayaquil, Ecuador
Haiphong, Vietnam
Hong Kong, People's Republic of China
Honolulu, Hawaii, United States
Incheon, South Korea
Iloilo, Philippines
Iquique, Chile
Jayapura, Indonesia
Kaohsiung, Republic of China (Taiwan)
Kitimat, British Columbia, Canada
Keelung, Republic of China (Taiwan)
Kobe, Japan
Kuala Terengganu, Malaysia
Laem Chabang, Thailand
Lyttelton, New Zealand
Long Beach, California, United States
Los Angeles, California, United States
Manta, Ecuador
Manzanillo, Colima, Mexico
Mazatlán, Sinaloa, Mexico
Melbourne, Victoria, Australia
Manila, Philippines
Nampho, North Korea
Newcastle, New South Wales, Australia
Oakland, California, United States
Panama City, Panama
Portland, Oregon, United States
Portoviejo, Ecuador
Prince Rupert, British Columbia, Canada
Puerto Chacabuco, Chile
Puerto Montt, Chile
Puerto Vallarta, Jalisco, Mexico
Qingdao, People's Republic of China
Saigon, Vietnam
San Antonio, Chile
San Diego, California, United States
San Francisco, California, United States
Seattle, Washington, United States
Shanghai, People's Republic of China
Shenzhen, People's Republic of China
Singapore
Songkhla, Thailand
Sydney, New South Wales, Australia
Tacoma, Washington, United States
Taichung, Republic of China (Taiwan)
Talcahuano, Chile
Tauranga, New Zealand
Tianjin, People's Republic of China
Tijuana, Baja California, Mexico
Tokyo, Japan
Valparaíso, Chile
Vancouver, British Columbia, Canada
Victoria, British Columbia, Canada
Vladivostok, Russia
Xiamen, People's Republic of China
Yantai, People's Republic of China
Yokohama, Japan
Zamboanga, Philippines
Resources:
http://en.wikipedia.org/wiki/Pacific_Ocean
http://www.ceoe.udel.edu/extreme2004/mission/divelocation/pacific.html
http://geography.about.com/library/cia/blcpacific.htm
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