TITLE:
Agroclimatological Characteristics of Rainy Seasons in Southwestern Burkina Faso during the 1970-2013 Period
AUTHORS:
Boubacar Ibrahim, Moussa Waongo, Moussa Sidibe, Safietou Sanfo, Boubacar Barry
KEYWORDS:
Climate Variability, Rainy Season, Dry Spell, Hot Spell, Burkina Faso
JOURNAL NAME:
Atmospheric and Climate Sciences,
Vol.12 No.2,
April
1,
2022
ABSTRACT: The different drought phases observed during the 1970-2010 period have underlined important weaknesses of West African
agricultural systems. The droughts resulted in important decreases in crop
production, triggering a significant deficit in food availability. Many studies
have identified changes in rain events seasonal patterns as the key drivers of
agricultural production failure during these
drought phases. In this study, seven agriculturally-relevant intra-seasonal rainfall characteristics (i.e.,
annual rainfall amount, onset and cessation of the rainy season, dry spells,
extreme rain events, hot spells, and strong winds) and associated constraints
to crop growth are described for the main cereals (maize, millet, and sorghum)
in southwestern Burkina Faso. These characteristics are calculated or
determined using daily climate data from a local network of 16 weather stations
spanning the 1970-2013
period. A computation of the intensity and the occurrence of these phenomena
during the rainy seasons helped to draw the rainy seasons’ nomenclature.
Findings suggest that the rainy seasons during the drought phases are
characterized by low annual rainfall amount, late onset, early cessation and
more frequent long dry spells (>7 days). Furthermore, the long dry spells mostly occurred during the most
sensitive phases of crop development: germination at the beginning of the rainy
season and flowering at the end of the rainy season. Also, the intensity and
the probability of occurrence of the other extreme events (hot spells and
strong winds) during rainy seasons are very high in the establishment phase. Thus,
adaptation strategies to mitigate these unfavorable climate conditions include a selection of short-cycle
crop varieties combined with supplementary irrigation systems during long dry
spells.