Geography of Guyana

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Geography of Guyana
Guyana rel 1991.gif
Continent South America
Region3Caribbean
Coordinates 5°00′N59°00′W / 5.000°N 59.000°W / 5.000; -59.000
Area Ranked 83rd
  Total214,969 km2 (83,000 sq mi)
  Land91.57%
  Water8.43%
Coastline459 km (285 mi)
Borderstotal length 2,933 km (1,822 mi)
Highest point Mount Roraima
2,835 metres (9,301 ft)
Lowest point Caribbean Sea
0 metres (0 ft)
Longest river Essequibo River
1,010 km (630 mi)
Largest lake Mainstay Lake
19,500 km (12,100 mi)
Exclusive economic zone137,765 km2 (53,191 sq mi)

The Geography of Guyana comprises the physical characteristics of the country in Northern South America and part of Caribbean South America, bordering the North Atlantic Ocean, between Suriname and Venezuela, with a land area of approximately 214,969 square kilometres. The country is situated between 1 and 9 north latitude and between 56 and 62 west longitude. With a 459 km (285 mi)-long Atlantic coastline on the northeast, Guyana is bounded by Venezuela on the west, Brazil on the west and south, and Suriname on the east. The land comprises three main geographical zones: the coastal plain, the white sand belt and the interior highlands.

Contents

Description

The coastal plain, which occupies about 5 percent of the country's area, is home to more than 90 percent of its inhabitants. The plain ranges from 26 to 77 kilometers wide and extends from the Corentyne River in the east to the Venezuelan border in the northwest.

The coastal plain is made up largely of alluvial mud swept out to sea by the Amazon River, carried north by ocean currents, and deposited on the Guyanese shores. A rich clay of great fertility, this mud overlays the white sands and clays formed from the erosion of the interior bedrock and carried seaward by the rivers of Guyana. Because much of the coastal plain floods at high tide, efforts to dam and drain this area have gone on since the 18th century.

Guyana has no well-defined shoreline or sandy beaches. Approaching the ocean, the land gradually loses elevation until it includes many areas of marsh and swamp. Seaward from the vegetation line is a region of mud flats, shallow brown water, and sandbars. Off New Amsterdam, these mud flats extend almost 25 kilometres (16 mi). The sandbars and shallow water are a major impediment to shipping, and incoming vessels must partially unload their cargoes offshore in order to reach the docks at Georgetown and New Amsterdam.

A line of swamps forms a barrier between the white sandy hills of the interior and the coastal plain. These swamps, formed when water was prevented from flowing onto coastal croplands by a series of dams, serve as reservoirs during periods of drought.

The white sand belt lies south of the coastal zone. This area is 150 to 250 kilometers wide and consists of low sandy hills interspersed with rocky outcroppings. The white sands support a dense hardwood forest. These sands cannot support crops, and if the trees are removed erosion is rapid and severe. Most of Guyana's reserves of bauxite, gold, and diamonds are found in this region.

The largest of Guyana's three geographical regions is the interior highlands, a series of plateaus, flat-topped mountains, and savannahs that extend from the white sand belt to the country's southern borders. The Pacaraima Mountains dominate the western part of the interior highlands. In this region are found some of the oldest sedimentary rocks in the Western Hemisphere. Mount Roraima, on the Venezuelan border, is part of the Pakaraima range and, at 2,762 meters, is Guyana's tallest peak. Farther south lies the Kaieteur Plateau, a broad, rocky area about 600 meters in elevation; the 1,000-meter high Kanuku Mountains; and the low Acarai Mountains situated on the southern border with Brazil.

Much of the interior highlands consist of grassland. The largest expanse of grassland, the Rupununi Savannah, covers about 15,000 square kilometers in southern Guyana. This savannah also extends far into Venezuela and Brazil. The part in Guyana is split into northern and southern regions by the Kanuku Mountains. The sparse grasses of the savannah in general support only grazing, although Amerindian groups cultivate a few areas along the Rupununi River and in the foothills of the Kanuku Mountains. The country of Guyana consists of four main natural regions: The hilly sand and clay region, the interior Savannah, the forested highlands and the low coastal plains.

Hydrology

Map of the Essequibo drainage basin Essequiborivermap.png
Map of the Essequibo drainage basin


Guyana is a water-rich country. Numerous rivers flow into the Atlantic Ocean, generally in a northward direction. A number of rivers in the western part of the country, however, flow eastward into the Essequibo River, draining the Kaieteur Plateau. The Essequibo, the country's major river, runs from the Brazilian border in the south to a wide delta west of Georgetown. The rivers of eastern Guyana cut across the coastal zone, making east-west travel difficult, but they also provide limited water access to the interior.

Waterfalls generally limit water transport to the lower reaches of each river. Some of the waterfalls are spectacular; for example, Kaieteur Falls on the Potaro River drops 251 metres, more than four times the height of Niagara Falls. Other enormous waterfalls are King Edward VIII Falls (256 m), Kumerau Falls (190 m), Oshi Falls (160 – 210 m). In the country are known to exist more than 200 rapids and more than 70 large waterfalls. Many waterfalls are little known and most are not measured yet, it is possible that there are waterfalls in excess of 300 m tall.

Drainage throughout most of Guyana is poor and river flow sluggish because the average gradient of the main rivers is only one meter every five kilometers. Swamps and areas of periodic flooding are found in all but the mountainous regions, and all new land projects require extensive drainage networks before they are suitable for agricultural use. The average square kilometer on a sugar plantation, for example, has six kilometers of irrigation canals, eighteen kilometers of large drains, and eighteen kilometers of small drains. These canals occupy nearly one-eighth of the surface area of the average sugarcane field. Some of the larger estates have more than 550 kilometers of canals; Guyana itself has a total of more than 8,000 kilometers. Even Georgetown is below sea level and must depend on dikes for protection from the Demerara River and the Atlantic Ocean.

Climate

Guyana map of Koppen climate classification. Koppen-Geiger Map GUY present.svg
Guyana map of Köppen climate classification.
A few scattered fires (red dots) in northern South America: Venezuela (left), Guyana (right) and Brazil (bottom center) NSAmerica2.A2002363.1420.500m.jpg
A few scattered fires (red dots) in northern South America: Venezuela (left), Guyana (right) and Brazil (bottom center)

Lying near the equator, Guyana has a tropical climate, and temperatures do not vary much throughout the year. The year has two wet seasons, from December to early February and from late April to mid-August.

Although the temperature never gets dangerously high, the combination of heat and humidity can at times seem oppressive. The entire area is under the influence of the northeast trade winds, and during the midday and afternoon sea breezes bring relief to the coast. Guyana lies south of the path of Caribbean hurricanes and none is known to have hit the country.

Temperatures in Georgetown are quite constant, with an average high of 32 °C (89.6 °F) and an average low of 24 °C (75.2 °F) in the hottest month (July), and an average range of 29 to 23 °C (84.2 to 73.4 °F) in February, the coolest month. The highest temperature ever recorded in the capital was 37.7 °C (99.9 °F) and the lowest 16.6 °C (61.9 °F). Humidity averages 70 percent year-round. Locations in the interior, away from the moderating influence of the ocean, experience slightly wider variations in daily temperature, and readings between 13 °C (55.4 °F) and 39 °C (102.2 °F) have been recorded. Humidity in the interior is also slightly lower, averaging around 60 percent.

Rainfall is heaviest in the northwest and lightest in the southeast and interior. Annual averages on the coast near the Venezuelan border are near 2,500 millimetres (98.4 in), farther east at New Amsterdam, between 2,000 and 1,500 millimetres (78.7 and 59.1 in) in southern Guyana's Rupununi Savannah. Areas on the northeast sides of mountains that catch the trade winds average as much as 3,500 millimetres (137.8 in) of precipitation annually. Although rain falls throughout the year, about 50 percent of the annual total arrives in the summer rainy season that extends from May to the end of July along the coast and from April through September farther inland. Coastal areas have a second rainy season from November through January. Rain generally falls in heavy afternoon showers or thunderstorms. Overcast days are rare; most days include four to eight hours of sunshine from morning through early afternoon.

Characteristics

Geographic coordinates: 5°00′N59°00′W / 5.000°N 59.000°W / 5.000; -59.000

Economic activity map of Guyana Guyana econ 1973.jpg
Economic activity map of Guyana

Area

Land boundaries

Coastline

Maritime claims

  • Territorial sea: 12 nmi (22.2 km; 13.8 mi)
  • Exclusive economic zone: 137,765 km2 (53,191 sq mi) and 200 nmi (370.4 km; 230.2 mi)
  • Continental shelf: 200  nmi (370.4 km; 230.2 mi) or to the outer edge of the continental margin

Terrain

Mostly rolling highlands; low coastal plain; savanna in south.

Elevation extremes

Natural resources

Bauxite, gold, diamonds, hardwood timber, shrimp, fish.

Vegetation map of Guyana Guyana veg 1973.jpg
Vegetation map of Guyana

Land use

Irrigated land

Total renewable water resources

Freshwater withdrawal (domestic/industrial/agricultural)

Natural hazards

Environment, current issues

Environment - international agreements

Party to: Biodiversity, Climate Change, Desertification, Endangered Species, Hazardous Wastes, Law of the Sea, Ozone Layer Protection, Ship Pollution, Tropical Timber 83, Tropical Timber 94

Extreme points

See also

Related Research Articles

The transport sector comprises the physical infrastructure, docks and vehicle, terminals, fleets, ancillary equipment and service delivery of all the various modes of transport operating in Guyana. The transport services, transport agencies providing these services, the organizations and people who plan, build, maintain, and operate the system, and the policies that mold its development.

Geography of Suriname

Suriname is located in the northern part of South America and is part of Caribbean South America, bordering the North Atlantic Ocean, between French Guiana and Guyana. It is mostly covered by tropical rainforest, containing a great diversity of flora and fauna that, for the most part, are increasingly threatened by new development. There is a relatively small population, most of which live along the coast.

Geography of Venezuela

Venezuela is a country in South America, bordering the Caribbean Sea and the North Atlantic Ocean, between Colombia and Guyana. It is situated on major sea and air routes linking North and South America. Located at the northernmost end of South America, Venezuela has a total area of 916,445 km2 (353,841 sq mi) and a land area of 882,050 km2 (340,560 sq mi). It is the 32nd largest country, about twice the size of California. Shaped roughly like an inverted triangle, the country has a 2,800 km (1,700 mi) long coastline. It is bound on the north by the Caribbean Sea and the Atlantic Ocean, on the east by Guyana, on the south by Brazil, and on the west by Colombia. It has the 55th largest Exclusive Economic Zone of 471,507 km2 (182,050 sq mi). Its maritime territory borders Trinidad and Tobago, Dominica, the Dominican Republic, Grenada, St. Kitts and Nevis, St. Vincent and the Grenadines, France, the United Kingdom, the Netherlands, and the United States.

Guiana Shield Precambrian geological formation in northeast South America, and one of three cratons of the South American Plate

The Guiana Shield is one of the three cratons of the South American Plate. It is a 1.7 billion-year-old Precambrian geological formation in northeast South America that forms a portion of the northern coast. The higher elevations on the shield are called the Guiana Highlands, which is where the table-like mountains called tepuis are found. The Guiana Highlands are also the source of some of the world's most well-known waterfalls such as Angel Falls, Kaieteur Falls and Kuquenan Falls.

Essequibo River

The Essequibo River is the largest river in Guyana, and the largest river between the Orinoco and Amazon. Rising in the Acarai Mountains near the Brazil–Guyana border, the Essequibo flows to the north for 1,014 kilometres (630 mi) through forest and savanna into the Atlantic Ocean. With a total drainage basin of 151,000 square kilometres (58,000 sq mi) and an average discharge of 4,531 cubic metres per second (160,000 cu ft/s).

Lethem, Guyana Town and regional capital in Upper Takutu-Upper Essequibo, Guyana

Lethem is a town in Guyana, located in the Upper Takutu-Upper Essequibo region. It is the regional capital of Upper Takutu-Upper Essequibo.

Rupununi River in Guyana

The Rupununi is a region in the south-west of Guyana, bordering the Brazilian Amazon. The Rupununi river, also known by the local indigenous peoples as Raponani, flows through the Rupununi region. The name Rupununi originates from the word rapon in the Makushi language, in which it means the black-bellied whistling duck found along the river.

Acarai Mountains

The Acarai Mountains are a wet, forested highland region of low mountains located in the southern part of Guyana. This range lies along the common border between Guyana and Brazil. The Acarai Mountains is one of four mountain ranges in Guyana, the others being the Imataka, Kanuku and Pakaraima mountains. The headwaters of the Essequibo River, the longest river in Guyana, and the Courantyne River, have their sources in this range. The actual source of the Essequibo was discovered in 2013 by a Guyanese-German team. The mountain range was first mentioned in 1821 by A.H. Brué as Sierra do Acaray.

Pacaraima Mountains

The Pacaraima or Pakaraima Mountains are a mountain range primarily in southwestern Guyana, and into northern Brazil and eastern Venezuela.

Kanuku Mountains Mountain range in Guyana

The Kanuku Mountains are a group of mountains in Guyana, located in the Upper Takutu-Upper Essequibo region. The name means 'forest' in the Wapishana language, a reference to the rich diversity of wildlife found there. The Eastern Kanuku Mountains and the Western Kanuku Mountains are separated by the Rupununi River. In 2011, the mountains were designated National Protected Area.

Rupununi savannah

The Rupununi savannah is a savanna plain in Guyana, in the Upper Takutu-Upper Essequibo region. It is an ecoregion of the Tropical and subtropical grasslands, savannas, and shrublands Biome.

Guayana Region, Venezuela Administrative region of eastern Venezuela

The Guayana Region is an administrative region of eastern Venezuela.

Long-tailed potoo Species of bird

The long-tailed potoo is a species of bird in the Nyctibiidae family. It is found in Brazil, Venezuela, Guyana, Colombia, Ecuador, Peru, Bolivia, and Paraguay; also in Argentina in the extreme northeast. Its natural habitat is subtropical or tropical moist lowland forests.

Guyana Country in South America

Guyana, officially the Co‑operative Republic of Guyana, is a country on the northern mainland of South America and the capital city is Georgetown. Guyana is bordered by the Atlantic Ocean to the north, Brazil to the south and southwest, Venezuela to the west, and Suriname to the east. With 215,000 square kilometres (83,000 sq mi), Guyana is the third-smallest sovereign state by area in mainland South America after Uruguay and Suriname; it is also the second-least populous sovereign state in South America after Suriname.

Kamarang River

Kamarang River is a river in Venezuela and Guyana, and a part of the Essequibo River basin.

The North Rupununi District in located in south-west Guyana consisting of a mixture of forest, savannah and wetlands ecosystems and is considered one of the most diverse areas in South America. Located on the eastern margin of the larger savannah system which extends into Brazil and is separated by the Ireng and Takutu rivers that come together to form the Rio Branco. The Guyana Rupununi system is divided into the North and South Rupununi by the Kanuku Mountains.

Surama Amerindian village in Upper Takutu-Upper Essequibo, Guyana

Surama is an Amerindian village in the North Rupununi area and the Upper Takutu-Upper Essequibo Region of Guyana, with a population of 274 people as of 2012.

Guianan Highlands moist forests

The Guayanan Highlands moist forests (NT0124) is an ecoregion in the south of Venezuela and the north of Brazil and in Guyana, Suriname, French Guiana. It is in the Amazon biome. It encompasses an upland region with diverse fauna and flora, which contains dramatic tepuis, or sandstone table mountains. The region has been inaccessible in the past and is generally fairly intact, apart from the north and northeast where large scale agriculture, ranching and mining operations are steadily encroaching on the ecosystem. New roads are opening the interior to logging, and planned dams will have a drastic impact on the riparian zones.

Guianan moist forests

The Guianan moist forests (NT0125) is an ecoregion in the east of Venezuela, north of Brazil and the Guyanas. It is in the Amazon biome. The climate is hot and humid, with two rainy seasons each year. As of 1996 the tropical rainforest habitat was relatively intact, although there were mounting threats from illegal logging and gold mining.

St. Ignatius, Guyana Amerindian village in Upper Takutu-Upper Essequibo, Guyana

St. Ignatius is an Amerindian village in the Upper Takutu-Upper Essequibo region of Guyana, near the regional capital Lethem and the border of Brazil. It was originally a mission founded by Jesuit priests to serve the Amerindians in the Rupununi savannah.

References