The Dominican Republic is located on the island of Hispaniola (La
Isla Espa�ola), which it shares with Haiti to the west. The
388-kilometer border between the two was established in a series of
treaties, the most recent of which was the 1936 Protocol of Revision of
the Frontier Treaty (Tratado Fronterizo) of 1929. The country is shaped
in the form of an irregular triangle. The short side of the triangle is
388 kilometers long, while the two long sides form 1,575 kilometers of
coastline along the Atlantic Ocean, the Caribbean Sea, and the Mona
Passage. The total area of the country is approximately 48,442 square
kilometers. Although it boasts the highest elevations in the Antilles,
it also has a saltwater lake below sea level.
Natural Regions
The mountains and valleys of the Dominican Republic divide the
country into the northern, the central, and the southwestern regions.
The northern region, bordering the Atlantic Ocean, consists of the
Atlantic coastal plain, the Cordillera Septentrional (or Northern
Mountain Range), the Valle del Cibao (Cibao Valley), and the Saman�
Peninsula. The Atlantic coastal plain is a narrow strip that extends
from the northwestern coast at Monte Cristi to Nagua, northwest of the
Saman� Peninsula. The Cordillera Septentrional is south of, and runs
parallel to, the coastal plain. Its highest peaks rise to an elevation
of over 1,000 meters. The Valle del Cibao lies south of the Cordillera
Septentrional. It extends 240 kilometers from the northwest coast to the
Bah�a de Saman� in the east and ranges in width from 15 to 45
kilometers. To the west of the ridge lies the Valle de Santiago and to
the east is the Valle de la Vega Real. The Saman� Peninsula is an
eastward extension of the northern region, separated from the Cordillera
Septentrional by an area of swampy lowlands. The peninsula is
mountainous; its highest elevations reach 600 meters.
The central region is dominated by the Cordillera Central (Central
Range); it runs eastward from the Haitian border and turns southward at
the Valle de Constanza (or Constanza Valley) to end in the Caribbean
Sea. This southward branch is known as the Sierra de Ocoa. The
Cordillera Central is 2,000 meters high near the Haitian border and
reaches a height of 3,087 meters at Pico Duarte, the highest point in
the country. An eastern branch of the Cordillera Central extends through
the Sierra de Yamas� to the Cordillera Oriental (Eastern Range). The
main peaks of these two mountain groups are not higher than 880 meters.
The Cordillera Oriental is also known as the Sierra de Seibo.
Another significant feature of the central region is the Caribbean
coastal plain, which lies south of the foothills of the Sierra de Yamas�
and the Cordillera Oriental. It extends 240 kilometers from the mouth of
the Ocoa River to the extreme eastern end of the island. The Caribbean
coastal plain is 10 to 40 kilometers wide and consists of a series of
limestone terraces that gradually rise to a height of 100 to 120 meters
at the northern edge of the coastal plains at the foothills of the
Cordillera Oriental. Finally, the central region includes the Valle de
San Juan in the western part of the country; the valley extends 100
kilometers from the Haitian border to the Bah�a de Ocoa.
The southwestern region lies south of the Valle de San Juan. It
encompasses the Sierra de Neiba, which extends 100 kilometers from the
Haitian border to the Yaque del Sur River. The main peaks are roughly
2,000 meters high, while other peaks range from 1,000 to 1,500 meters.
On the eastern side of the Yaque del Sur lies the Sierra de Mart�n Garc�a,
which extends twenty-five kilometers from the river to the Llanura de
Azua (Plain of Azua).
The Hoya de Enriquillo, a structural basin that lies south of the
Sierra de Neiba, is also within the southwestern region. The basin
extends ninety-five kilometers from the Haitian border to the Bah�a de
Neiba and twenty kilometers from the Sierra de Neiba to the Sierra de
Baoruco. The Sierra de Baoruco extends seventy kilometers from the
Haitian border to the Caribbean Sea. Its three major peaks surpass 2,000
meters in height. TheProcurrente de Barahona (Cape of Barahona) extends
southward from the Sierra de Baoruco and consists of a series of
terraces.
<>Rivers
The Dominican Republic has seven major drainage basins. Five of these
rise in the Cordillera Central and a sixth, in the Sierra de Yamas�.
The seventh drainage system flows into the Lago Enriquillo (Lake
Enriquillo) from the Sierra de Neiba to the north and from the Sierra de
Baoruco to the south. In general, other rivers are either short or
intermittent.
The Yaque del Norte is the most significant river in the country.
Some 296 kilometers long, with a basin area of 7,044 square kilometers,
it rises near Pico Duarte at an altitude of 2,580 meters in the
Cordillera Central. It empties into the Bah�a de Monte Cristi on the
northwest coast, where it forms a delta. The Yaque del Sur is the most
important river on the southern coast. It rises at an altitude of 2,707
meters in the southern slopes of the Cordillera Central. Its upper
course through the mountains constitutes 75 percent of its total length
of some 183 kilometers. The basin area is 4,972 square kilometers. The
river forms a delta near its mouth in the Bah�a de Neiba.
The Lago Enriquillo lies in the western part of the Hoya de
Enriquillo. Its drainage basin includes ten minor river systems and
covers an area of more than 3,000 square kilometers. The northern rivers
of the system rise in the Sierra de Neiba and are perennial, while the
southern rivers rise in the Sierra de Baoruco and are intermittent,
flowing only after heavy rainfall. The Lago Enriquillo itself covers
some 265 square kilometers. Its water level varies because of the high
evaporation rate, yet on the average it is forty meters below sea level.
The water in the lake is saline.
Dominican Republic - Climate
The Dominican Republic has primarily a tropical climate, with more
diurnal and local variations in temperature than seasonal ones, and with
seasonal variability in the abundance of rainfall. The average annual
temperature is 25� C, ranging from 18� C at an altitude of over 1,200
meters to 28� C at an altitude of 10 meters. Highs of 40� C are common
in protected valleys, as are lows of zero in mountainous areas. In
general, August is the hottest month, and January and February are the
coldest ones.
Seasons, however, vary more as a function of rainfall than of
temperature. Along the northern coast, the rainy season lasts from
November through January. In the rest of the country, it runs from May
through November; May is the wettest month. The dry season lasts from
November through April; March is the driest month. The average annual
rainfall for the country as a whole is 150 centimeters. This varies,
however, from region to region, and ranges from 35 centimeters in the
Valle de Neiba to 274 centimeters in the Cordillera Oriental. In
general, the western part of the country, including the interior
valleys, receives the least rain.
Tropical cyclones--such as tropical depressions, tropical storms, and
hurricanes--occur on the average of once every two years in the
Dominican Republic. Over 65 percent of the storms strike the southern
part of the country, especially along the Hoya de Enriquillo. The season
for cyclones lasts from the beginning of June to the end of November;
some cyclones occur in May and December, but most take place in
September and October. Hurricanes usually occur from August through
October. They may produce winds greater than 200 kilometers per hour and
rainfall greater than 50 centimeters in a twenty-four-hour period.
