Web Page Research & Design

Minnha Tran and Paris Rogers

Climate

Land of Wood and Water

Jamaica’s climate is determined as tropical maritime which is influenced by the sea and the temperature rarely changes, although the mountains cause regional varitions.  The island lies between, “the subtropical high-pressure and equatorial low-pressure belts of the Alantic Ocean, so the northeast trade winds are dominant throughout the year.” (Encyclopedia Brittanica)  It also has a hot and humid interior that effects such regions as Liguanea and the southern part of the island, which is in a rain shadow. (Water Resources Authority)

 

 The Encyclopedia Brittiannica tells us that Jamaica, “during the winter months, from December to March, cold winds known locally as "northers" reach the island through the wide, open trough of the North American plains.” (Encyclopedia Britannica)

            

Water Resources Authority states that the, “Long term mean annual rainfall over the Island is about 1,980 mm (78 in.).  Daily mean temperatures range from a seasonal low of 26 ° C in February to a high of 28 ° C in August. Daily sunshine hours are fairly constant throughout the year, averaging about 8.2 hours in the southern plains.”  (See fig A) (WRA)

            

The northeast trade winds cause rainfall on the island to fall on the northern slopes.  The Department of Geoography states, “Annual rainfall on the northeastern slopes of the Blue Mountain Range is generally 3,000 to 5,000 mm, whereas in the south coastal plains of St. Catherine and Clarendon less than 1,500 mm/yr (59 in.).” (Dept of Geography and Geology West Indies)

  

Patterns of annual rainfall in Jamaica are unique with the maximun of rain during the month of October and the minimum in May and their dry season lasts from December to April. (Water Resources Authority)

 

 The Geology Department of the West Indies tells us that Jamaica is regularly affected by the tropical storms and hurricanes from the period of July to November and some other influences that affect Jamaica are: “the warm waters of the Caribbean Sea, as well as the synoptic weather systems, primarily the Azores– Bermuda high-pressure system, surface mid and upper level troughs, frontal systems, easterly waves, tropical depressions, tropical storms, hurricanes and infrequently the inter-tropical convergence zone.” (Dept of Geography and Geology West Indies)

            

 We find that Jamaica falls under the tropical/dry tropical maritime climate and that the temperature of Jamaica never really changes except in the mountains.  The island lies on both high sub-tropical and low equatorial pressure belts with an annual rainfall of 78 inches. Sunshine is constant during the year averaging about 8.2 hours.  Jamaica is also regularly affected by tropical storms and hurricanes.

Fig A

Maps courtesy of WRA