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P. Sagna et al.
2 Data and Methodology
2.1 The Four Countries Included in the Study
The four countries chosen for this study, Ivory Coast, Benin, Burkina Faso, and
Senegal (Fig. 1), experience climatic similarities and differences. The similarities are
in circulation mechanisms and disturbances; the differences are mainly related to rainfall and temperature. As for surface atmospheric circulation, trade wind and monsoon
circulations have been observed to alternate, contributing different proportions of
wind frequencies. Average flows for the year 2014 illustrate this alternation:
• 13.8% for trade wind and 86.2% for monsoon in Ivory Coast;
• 18.4% for trade wind and 81.6% for monsoon in Benin;
• 40.5% for trade wind and 59.5% for monsoon in Burkina Faso, and
• 58% for trade wind and 42% for monsoon in Senegal.
Precipitation is mainly from squall lines, especially in Senegal and Burkina Faso,
while the proportion from the Intertropical Convergence Zone (ITCZ) is very high
in the south of Ivory Coast and Benin. There are also orographic and thermal factors,
as well as cyclonic disturbances, all of which have impacts on precipitation. Overall,
given the dynamics of precipitation, the southern countries (Ivory Coast and Benin)
have higher levels of rainfall than the northern countries (Burkina Faso and Senegal).
Fig. 1 Countries studied
P. Sagna et al.
2 Data and Methodology
2.1 The Four Countries Included in the Study
The four countries chosen for this study, Ivory Coast, Benin, Burkina Faso, and
Senegal (Fig. 1), experience climatic similarities and differences. The similarities are
in circulation mechanisms and disturbances; the differences are mainly related to rainfall and temperature. As for surface atmospheric circulation, trade wind and monsoon
circulations have been observed to alternate, contributing different proportions of
wind frequencies. Average flows for the year 2014 illustrate this alternation:
• 13.8% for trade wind and 86.2% for monsoon in Ivory Coast;
• 18.4% for trade wind and 81.6% for monsoon in Benin;
• 40.5% for trade wind and 59.5% for monsoon in Burkina Faso, and
• 58% for trade wind and 42% for monsoon in Senegal.
Precipitation is mainly from squall lines, especially in Senegal and Burkina Faso,
while the proportion from the Intertropical Convergence Zone (ITCZ) is very high
in the south of Ivory Coast and Benin. There are also orographic and thermal factors,
as well as cyclonic disturbances, all of which have impacts on precipitation. Overall,
given the dynamics of precipitation, the southern countries (Ivory Coast and Benin)
have higher levels of rainfall than the northern countries (Burkina Faso and Senegal).
Fig. 1 Countries studied