GEO Haiti 2010

State of the Environment Report 2010
The country receives annually a volume of 40
billion m 3 of water, of which 60% of it returns
into the water cycle through evaporation
(GEORGES, 2008). In spite of an average annual
rainfall of nearly 1,400 mm, the pluviometry
however presents high variations to the extent
that some regions receive amounts exceeding
4,000 mm while others only 350 mm over the
same period.
Rainfall also shows a defined temporal variation
as a result of trade winds, northern, eastern and
local winds which are often blowing in opposite
directions. The resulting rainfall pattern, very
unequal from the seasonal point of view, has
divided the year into two rainy seasons and
two dry seasons. The first ones run from March
to May and from August to October, while the
others run from November to February and
from June to July.
The following figures 8-11 provide interesting
information on rainfall and monthly
temperature at national scale. Figure 8 shows
that at the beginning of the rainy season (April-
May), the heaviest rainfall affects the entire
country (60 mm and 400 mm), especially in the
south, followed by the central region receiving
between 200 mm and 400 mm of water in the
month of May. The Artibonite region receives
the least amount of rainfall, more precisely,
the plains of Gonaïves (between 0 to 20 mm
of water). However, the average monthly
temperatures between March and May vary
according to region and altitude, between
12 °C and 28 °C. Average temperatures between
25 °C and 28 °C are recorded in the coastal
regions, the Gonaïves plain and in the west.
The lowest average temperatures, between
12 °C and 20 °C, are recorded in the mountainous
regions, the Massif de la Hotte, the Massif de
Selle, the Matheux Mountain range and Morne
Bonhomme.
During the rainy season which runs from August
to October, rainfall is more abundant than in the
March to May period. In fact, there is between
120 mm and 400 mm of rainfall in October. In the
Figure 8: Average monthly rainfall and
temperature from March to May
Source: Élabore par CATHALAC avec des données du Wordclim (1961-1990)
Source: Wordclim, 1961-1990)
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