Caribbean Islands Table of Contents
Grenada and its largely uninhabited outlying territories are the most southerly of the Windward Islands (see fig. 1). The Grenadine Islands chain consists of some 600 islets; those south of the Martinique Channel belong to Grenada, while those north of the channel are part of the nation of St. Vincent and the Grenadines. Located about 160 kilometers north of Venezuela, at approximately 12° north latitude and 61° west longitude, Grenada and its territories occupy a total area of 433 square kilometers. Grenada, known as the Spice Isle because of its production of nutmeg and mace, is the largest at 310 square kilometers, or about the size of Detroit. The island is oval in shape and framed by a jagged southern coastline; its maximum width is thirty-four kilometers, and its maximum length is nineteen kilometers. St. George's, the capital and the nation's most important harbor, is favorably situated near a lagoon on the southwestern coast. Of all the islands belonging to Grenada, only two are of consequence: Carriacou, with a population of a few thousand, and its neighbor Petit Martinique, roughly 40 kilometers northeast of Grenada and populated by some 700 inhabitants (see fig. 12).
Part of the volcanic chain in the Lesser Antilles arc, Grenada and its possessions generally vary in elevation from under 300 meters to over 600 meters above sea level. Grenada is more rugged and densely foliated than its outlying possessions, but other geographical conditions are more similar. Grenada's landmass rises from a narrow, coastal plain in a generally north-south trending axis of ridges and narrow valleys. Mount St. Catherine is the highest peak at 840 meters.
Although many of the rocks and soils are of volcanic origin, the volcanic cones dotting Grenada are long dormant. Some of the drainage features on Grenada remain from its volcanic past. There are a few crater lakes, the largest of which is Grand Etang. The swift upper reaches of rivers, which occasionally overflow and cause flooding and landslides, generally cut deeply into the conic slopes. By contrast, many of the water courses in the lowlands tend to be sluggish and meandering.
The abundance of water is primarily caused by the tropical, wet climate. Yearly precipitation, largely generated by the warm and moisture-laden northeasterly trade winds, varies from more than 350 centimeters on the windward mountainsides to less than 150 centimeters in the lowlands. The greatest monthly totals are recorded throughout Grenada from June through November, the months when tropical storms and hurricanes are most likely to occur. Rainfall is less pronounced from December through May, when the equatorial low-pressure system moves south. Similarly, the highest humidities, usually close to 80 percent, are recorded during the rainy months, and values from 68 to 78 percent are registered during the drier period. Temperatures averaging 29°C are constant throughout the year, however, with slightly higher readings in the lowlands. Nevertheless, diurnal ranges within a 24-hour period are appreciable: between 26°C and 32°C during the day and between 19°C and 24°C at night.
Data as of November 1987