Atlantic Ocean

The ocean between the Americas, Europe and Africa

Overview

The Atlantic Ocean is the second-largest of Earth's five major oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean around Antarctica.

The Atlantic separates the Americas from Europe and Africa. It is an important component of the global ocean circulation system and plays a major role in climate, weather, ecosystems, shipping and international trade.

The Atlantic is also geologically significant because its seafloor contains the Mid-Atlantic Ridge, one of the world's great tectonic features.

Key fact: The Atlantic Ocean covers approximately 106 million km² when its marginal seas are included, although published figures vary according to the boundaries used.

Geography of the Atlantic Ocean

The Atlantic Ocean occupies a long north-south basin between the eastern coastlines of North and South America and the western coastlines of Europe and Africa.

Its shape is approximately an elongated "S", reflecting the geological history of the breakup of the supercontinent Pangaea.

Continents bordering the Atlantic

Important geographical regions

Size and Depth

Property Approximate value
Area Approximately 106 million km² including marginal seas
Average depth Approximately 3,600 m
Deepest region Milwaukee Deep, Puerto Rico Trench
Maximum depth Approximately 8,400 m
Major ridge Mid-Atlantic Ridge

The Atlantic is considerably smaller than the Pacific Ocean, but its enormous north-south extent makes it an important part of global ocean circulation.

The Atlantic Ocean Seafloor

The Atlantic seafloor contains a complex system of ridges, abyssal plains, trenches, fracture zones, seamounts and continental margins.

Major features include:

The Mid-Atlantic Ridge

The Mid-Atlantic Ridge is one of the most important geological features of the Atlantic Ocean.

It is a vast underwater mountain system extending approximately from the Arctic region towards Antarctica.

The ridge marks a divergent plate boundary where tectonic plates move apart and new oceanic crust is formed.

Plate tectonics: The Atlantic Ocean is gradually widening as new oceanic crust forms along the Mid-Atlantic Ridge.

Plate Tectonics and the Atlantic

The present Atlantic Ocean began developing when the continents of the former supercontinent Pangaea started to separate.

North America moved away from Europe, while South America separated from Africa.

New oceanic crust continued to form between these continents, producing the Atlantic basin that exists today.

The Atlantic therefore provides one of the clearest examples of seafloor spreading and continental drift.

The Puerto Rico Trench

The Puerto Rico Trench is located in the western North Atlantic between Puerto Rico and the island of Hispaniola.

It is the deepest part of the Atlantic Ocean and reaches depths of more than 8 kilometres.

The trench is associated with complex tectonic interactions between the North American and Caribbean plates.

Major Seas of the Atlantic

The Atlantic Ocean contains numerous marginal seas, gulfs, bays and straits.

Sea / Gulf Location
North Sea Between Great Britain and continental Europe
Baltic Sea Northern Europe
Mediterranean Sea Between Europe, Africa and Asia
Caribbean Sea Between Central America and the Caribbean islands
Gulf of Mexico Between the United States, Mexico and Cuba
Gulf of Guinea West Africa
Labrador Sea Between Greenland and Canada
Norwegian Sea Between Norway, Iceland and the Faroe Islands
Irish Sea Between Ireland and Great Britain

Islands of the Atlantic Ocean

The Atlantic contains thousands of islands and archipelagos. Some are continental islands, while others are volcanic or coral islands.

Major Atlantic islands and island groups

Iceland

Iceland is one of the most geologically interesting islands in the Atlantic.

The island lies directly across the Mid-Atlantic Ridge and is therefore characterised by volcanic activity, geothermal energy, glaciers and extensive volcanic landscapes.

The Azores

The Azores are a volcanic archipelago located in the central North Atlantic.

Their position near the Mid-Atlantic Ridge makes them an important region for studying Atlantic tectonics and volcanism.

Atlantic Ocean Currents

Ocean currents are fundamental to the Atlantic climate system. They transport heat between the tropics and higher latitudes.

Major currents

The Gulf Stream

The Gulf Stream is a powerful warm ocean current originating in the western North Atlantic.

It transports warm water northwards and contributes to the climate of the North Atlantic region.

Its continuation into the North Atlantic forms part of the broader circulation system that transports heat towards western Europe.

Atlantic Meridional Overturning Circulation

The Atlantic is a major component of the global thermohaline circulation.

The Atlantic Meridional Overturning Circulation, or AMOC, involves the large-scale movement of warm surface water northwards and colder, denser water southwards at depth.

This circulation transports heat and carbon and plays an important role in the climate system.

Climate of the Atlantic Ocean

The Atlantic extends from polar to tropical latitudes and therefore contains a wide variety of ocean climates.

North Atlantic

The North Atlantic contains cold polar waters as well as warm subtropical waters.

Tropical Atlantic

The tropical Atlantic contains warm waters and is an important source of atmospheric moisture.

South Atlantic

The South Atlantic extends from tropical waters to the Southern Ocean surrounding Antarctica.

Atlantic Hurricanes

The tropical North Atlantic is one of the world's major regions for tropical cyclone formation.

These storms are known as hurricanes in the Atlantic and northeastern Pacific.

Hurricanes can produce extremely strong winds, heavy rainfall, storm surges and coastal flooding.

Marine Life

The Atlantic Ocean contains highly diverse marine ecosystems extending from coastal waters to the deepest abyssal regions.

Marine mammals

Fish

Atlantic Coral Reefs

Coral reefs occur in tropical and subtropical regions of the Atlantic, particularly in the Caribbean and western Atlantic.

These ecosystems provide habitats for thousands of marine species and help protect tropical coastlines from wave energy.

Deep-Sea Ecosystems

The deep Atlantic contains extensive abyssal plains, seamounts, cold-water coral ecosystems and hydrothermal environments.

Organisms living in the deep ocean must survive extreme pressure, darkness and low temperatures.

Resources of the Atlantic Ocean

The Atlantic supports major fisheries, shipping routes, offshore energy industries, tourism and marine research.

Major resources

Atlantic Fisheries

Fisheries have supported human communities around the Atlantic for thousands of years.

Important commercial fisheries include cod, herring, tuna, mackerel, sardines, shrimp and various shellfish.

Sustainable management is essential because excessive fishing pressure can reduce fish populations and disrupt marine food webs.

Oil and Gas

Petroleum and natural gas resources occur beneath portions of the Atlantic continental shelves.

Important offshore petroleum regions include areas around the North Sea, Gulf of Mexico, North Atlantic margins, West Africa and parts of South America.

Offshore Wind Energy

The Atlantic coastline has substantial potential for offshore wind power.

Countries bordering the North Atlantic and European Atlantic have developed extensive offshore wind industries, using large wind turbines installed in shallow and deeper continental-shelf waters.

Atlantic Shipping

The Atlantic is one of the world's most important maritime transportation systems.

Major shipping routes connect Europe, North America, South America, Africa and the Caribbean.

Important Atlantic ports include:

Exploration of the Atlantic

The Atlantic has played a central role in human exploration, migration and international trade.

Ancient Mediterranean and European peoples explored portions of the eastern Atlantic long before the age of transatlantic exploration.

Christopher Columbus

Christopher Columbus crossed the Atlantic in 1492 during a voyage sponsored by the Spanish Crown. His voyage initiated a major period of European exploration and colonisation of the Americas.

John Cabot

John Cabot crossed the North Atlantic in 1497 and reached the coast of North America.

Ferdinand Magellan

Magellan's expedition crossed the Atlantic before entering the Pacific through the strait at the southern end of South America.

The Atlantic and the Age of Sail

From the fifteenth century onwards, Atlantic maritime routes became central to global trade.

Ships carried people, goods and resources between Europe, Africa and the Americas, profoundly changing global history.

The Atlantic subsequently became a major centre of industrial shipping and international commerce.

Transatlantic Communications

The Atlantic was also an important obstacle and later a major route for global communications.

Nineteenth-century submarine telegraph cables eventually connected Europe and North America, dramatically reducing the time required to transmit information between the continents.

Atlantic Ocean and Aviation

The development of aviation transformed the Atlantic from a major physical barrier into a heavily travelled air corridor.

Modern aircraft routinely cross the North and South Atlantic, connecting Europe, Africa, North America and South America.

Atlantic Ocean and Science

Scientists study the Atlantic using research ships, satellites, autonomous underwater vehicles, remotely operated vehicles, ocean buoys, sonar and deep-sea instruments.

Major scientific subjects include:

Environmental Issues

The Atlantic faces many environmental pressures associated with climate change, human activity and increasing use of marine resources.

Climate change

Rising ocean temperatures and changing circulation patterns can affect ecosystems, fisheries, sea levels and coastal communities.

Ocean acidification

Increasing atmospheric carbon dioxide causes changes in ocean chemistry that can affect organisms which form calcium-carbonate shells or skeletons.

Plastic pollution

Plastic waste can enter the Atlantic from rivers, cities, shipping, fishing and coastal activities.

Overfishing

Unsustainable fishing can reduce fish populations and disrupt marine food webs.

Habitat destruction

Coastal development, pollution and changes to marine environments can damage wetlands, mangroves, seagrass beds and coral reefs.

The Atlantic and Global Climate

The Atlantic Ocean is a major component of Earth's climate system.

Its currents transport heat from tropical regions towards higher latitudes, while cold deep-water flows return towards the south.

The Atlantic therefore contributes to the redistribution of energy around the planet.

Atlantic Ocean and Europe

The Atlantic has had an enormous influence on the geography, climate, economy and history of Europe.

Countries such as the United Kingdom, Ireland, France, Spain, Portugal, Iceland and Norway have extensive Atlantic maritime connections.

The North Atlantic also influences the climate of western and northern Europe through the transport of warm ocean water.

Atlantic Ocean and Africa

The Atlantic forms the western coastline of Africa.

Important Atlantic regions include the Gulf of Guinea, Benguela Current system, Canary Current system and the southwest African continental margin.

Atlantic fisheries, ports, offshore energy and coastal ecosystems are important to many African countries.

Atlantic Ocean and the Americas

The Atlantic forms the eastern coastline of North and South America.

It connects the Americas with Europe and Africa through major shipping and aviation routes.

The Caribbean Sea and Gulf of Mexico form important marginal seas of the western Atlantic.

The Atlantic Ocean and Space Science

Satellites provide continuous observations of the Atlantic Ocean.

Satellite measurements are used to monitor:

Oceanography therefore combines Earth science, physics, mathematics, engineering, computing and satellite technology.

Quick Facts About the Atlantic Ocean

Feature Information
Name Atlantic Ocean
Approximate area About 106 million km² including marginal seas
Position Between the Americas and Europe/Africa
Largest ocean? No - the Pacific Ocean is larger
Major geological feature Mid-Atlantic Ridge
Deepest region Puerto Rico Trench
Important current Gulf Stream
Major circulation system Atlantic Meridional Overturning Circulation
Major marginal seas Mediterranean, Caribbean, North, Baltic and Norwegian Seas
Major climate phenomenon Atlantic hurricanes
Major economic activities Shipping, fisheries, offshore energy and tourism

Conclusion

The Atlantic Ocean is one of the most important geographical features on Earth. It separates the Americas from Europe and Africa while simultaneously connecting these continents through ocean circulation, trade, transportation and human history.

Its Mid-Atlantic Ridge provides a spectacular example of seafloor spreading and plate tectonics, while its powerful currents influence climates far beyond the ocean itself.

The Atlantic also contains highly productive fisheries, extensive marine ecosystems, deep ocean basins, island groups, coral reefs and important offshore energy resources.

From the Arctic waters of the North Atlantic to the Southern Ocean, the Atlantic is a fundamental component of the Earth's physical, biological and climatic systems.