Caribbean Seasuboceanic basin of the western Atlantic Ocean, lying between latitudes to and 22° N and longitudes 89° to and 60° W. It is approximately 1,063,000 square miles (2,754753,000 square kilometreskm) in extent. To the south it is bounded by the coasts of Venezuela, Colombia, and Panama; to the west by Costa Rica, Nicaragua, Honduras, Guatemala, Belize, and the Yucatán Peninsula of Mexico; to the north by the Greater Antilles islands of Cuba, Hispaniola, Jamaica, and Puerto Rico; and to the east by the Lesser Antilles chain, consisting of the island arc that extends from the Virgin Islands in the northeast to Trinidad, off the Venezuelan coast, in the southeast. Within the boundaries of the Caribbean itself, Jamaica, to the south of Cuba, is the largest of a number of islands.

Together with the Gulf of Mexico, the Caribbean Sea has been erroneously termed the American Mediterranean—owing Mediterranean, owing to the fact that, like the Mediterranean Sea, it is located between two continental landmasses. In neither hydrology nor climate, however, does the Caribbean resemble the Mediterranean. The preferred oceanographic term for the Caribbean is the Antillean-Caribbean Sea, which, together with the Gulf of Mexico, forms the Central American Sea. The Caribbean’s greatest known depth is Cayman Trench (Bartlett Deep) between Cuba and Jamaica, at approximately 25,216 feet (7,686 metres) below sea level.

Physical features

The geologic age of the Caribbean is not known with certainty. As part of the Central American Sea, it is presumed to have been connected with the Mediterranean during Paleozoic times (from about 570 to 245 i.e., about 540 to 250 million years ago) and then gradually to have separated from it as the Atlantic Ocean was formed. The ancient sediments overlying the seafloor of the Caribbean, as well as of the Gulf of Mexico, are called the Carib beds. They are about a half mile (about one kilometre) in thickness, with the upper strata representing sediments from the Mesozoic and Cenozoic eras (i.e., from 245 about 250 million years ago to the present) and the lower strata presumably representing sediments of the Paleozoic and Mesozoic eras. Three phases of sedimentation have been identified. During the first phase and second phases the basin was free of deformation, as it also was during the second phase, when the Carib beds were deposited. The Central American Sea apparently became separated from the Atlantic before the end of the first phase. Near the end of the second phase, gentle warping and faulting occurred, forming the Aves and Beata ridges. Forces producing the Panamanian isthmus and the Antillean arc were vertical, resulting in no ultimate horizontal movement. The Carib sediment beds tend to arch in the middle of the basins and to dip as landmasses are approached. The younger Cenozoic beds (formed during the last 66.4 65 million years) are generally horizontal, having been laid down after the deformations occurred. Connections were established with the Pacific Ocean during the Cretaceous Period (from about 144 to 66.4 65 million years ago) but were broken when the land bridges that permitted mammals to cross between North and South America were formed in the Miocene and Pliocene epochs (23.7 about 25 to 1.6 8 million years ago).

The existing sediment cover of the seabed consists of red clay in the deep basins and trenches, globigerina ooze (a calcareous marine deposit) on the rises, and pteropod ooze on the ridges and continental slopes. Clay minerals appear to have been washed down by the Amazon or and Orinoco rivers, as well as by the Magdalena River in Colombia. Coral reefs fringe most of the islands.



Subsurface water enters the Caribbean Sea across two sills. These sills are located below the Anegada Passage, which runs between the Virgin Islands and the Lesser Antilles, and the Windward Passage, which runs stretches between Cuba and Hispaniola. The sill depth of Anegada Passage is between 6,400 to and 7,700 feet (1,950 and 2,350 metres), whereas that of the Windward Passage is from between 5,250 to and 5,350 feet (1,600 and 1,630 metres).


North Atlantic Deep Water deep water enters the Caribbean beneath the Windward Passage and is characterized by its rich oxygen content and by a salinity of slightly less than 35 parts per thousand. From there it divides to fill the Yucatán, Cayman, and Colombian basins at depths near 6,500 feet (2,000 metres). This Caribbean Bottom Water bottom water also enters the Venezuelan Basin, thus introducing high-oxygen water at depths of between 5,900 and to 9,800 feet (1,800 to 3,000 metres). Subantarctic Intermediate Water intermediate water (i.e., water differing in several characteristics from the surface and bottom layers of water that it separates) enters the Caribbean below the Anegada Passage at depths of between 1,600 to 3,300 feet (500 to 1,000 metres). Above this water, the subtropical undercurrent and surface water both enter. The shallow sill depths of the Antillean arc block the entry of Antarctic Bottom Waterbottom water, so that the bottom temperature of the Caribbean Sea is close to 39° F (4° C39 °F (4 °C), as compared with the Atlantic bottom temperature of less than 36° F (2° C36 °F (2 °C).

Surface currents, bearing both high- and low-salinity water depending on the source, enter the Caribbean mainly through the channels and passages of the southern Antilles. These waters are then forced by the trade winds through the narrow Yucatán Channel into the Gulf of Mexico. The wind-driven surface water piles up accumulates in the Yucatán Basin and the Gulf of Mexico, where it results in a higher average sea level than in the Atlantic, forming a hydrostatic head that is believed to constitute the main driving force of the Gulf Stream. Of the water passing through the Yucatán Channel each second, only about one-fourth of it represents the deeper Subantarctic Intermediate Waterintermediate water. The remainder is the surface water that passed over the Antillean arc at depths of less than 2,600 feet (800 metres).


The climate of the Caribbean generally is tropical, but there are great local variations, depending on mountain altitudeelevation, water currents, and the trade winds. Rainfall varies from about 10 inches (250 millimetres25 cm) per year on the island of Bonaire off the coast of Venezuela to some 350 inches a year (900 cm) annually in parts of Dominica. The Northeast Trade Winds northeast trade winds dominate the region with an average velocity of 10 to 20 miles (16 to 32 km) per hour. Tropical storms reaching a hurricane velocity of more than 75 miles (120 km) per hour are seasonally common in the northern Caribbean as well as in the Gulf of Mexico; they are almost nonexistent in the far south. The hurricane season is from June to November, but hurricanes occur most frequently in September. The yearly average is about eight such storms. The Caribbean has fewer hurricanes than either the western Pacific (where these storms are called typhoons) or the Gulf of Mexico. Most hurricanes form in the eastern Atlantic near the Cape Verde Islands and follow the path of the trade winds into the Caribbean and the Gulf of Mexico, although the exact path of any hurricane is unpredictable. In 1963 Hurricane Flora one of the deadliest hurricanes on record, Flora, caused the loss of more than 7,000 lives and extensive property damage in the Caribbean alone. Such storms also have been a major cause of crop failure in the region.

Economic aspects





Tourism is an important part of the Caribbean economy, serving primarily the huge populations of the United States and Canada to the north and Brazil and Argentina to the south. Communications Connections by air and sea between the Caribbean and North America are far generally more developed than is are interisland communicationconnections. With its generally typically sunny climate and recreational resources, the Caribbean has become one of the world’s principal winter vacation resort areas.

Trade and transportation


Study and exploration



The invention of scuba equipment, the development of research submarines, and the establishment of marine research laboratories in a number of countries in the Caribbean region led to a rapid increase in the level of scientific activity following World War II. Since the signing of the Law of the Sea Treaty in the early 1980s, no part of the Caribbean remains outside the extended mineral, fishing, and territorial zones of the sea’s bordering countries. Explosive human population growth and the overexploitation of marine resources have stimulated international cooperation in pollution research, fisheries management, the monitoring of endangered species, and the establishment of marine parks and reserves in the basinin the second half of the 20th century. One of the more-recent areas of research has focused on coral "bleaching" events, including those in 1995 and 1998 off the coast of Belize (on the largest coral barrier reef in the Northern Hemisphere) and in 2005 on the reefs near Puerto Rico and the Virgin Islands. Coral bleaching occurs when the animals that constitute the reef expel associated algae in response to changes in water chemistry (temperature, salinity, acidity, or increases in silt or pollution). The process ultimately kills those animals. One of the leading hypotheses for this phenomenon has been that Caribbean waters have increased in temperature, perhaps as a result of global climate change.