Seasonal Variability of Climatic Parameters and Impacts on Food Crop Yields in the Western Plateau Region of Togo

Togolese agriculture is vulnerable to climate variability. In this context, this study aims to analyze the seasonal variability of climatic parameters and its effects on food production in the western Plateaux region. To achieve this, climatic data (from stations in Agou-Gare, Adéta, Amou, Badou, Kouma Konda, and Atakpamé) and agricultural data (yields, production, and areas of maize, rice, cowpea, cassava, and yam) from 1991 to 2020 were processed using RStudio 4.4.0. A methodology integrating both daily rainfall and changes in available soil water (ASW) was used to determine the rainy seasons and their durations. Seasonal rainfall totals were used to analyze spatial variability. Finally, an ordinary least squares (OLS) regression model with a threshold of 10% was used to assess the effect of climate parameters on food production. The results reveal a transition from a bimodal rainfall regime to a monomodal regime, characterised by a dry season of 4–5 months and a rainy season of 7–8 months. This transition is accompanied by an increase in temperatures ranging from 24.69 °C to 34.7 °C. The results also reveal an uncertain start to the long rainy season (early or late), an extension of the short season and dry spells lasting between 11 and 34 days that affect crops. Finally, spatial variability in precipitation remains significant during the long rainy season. Agroclimatic analysis reveals that maximum temperature positively influences cowpea yields (p = 0.0079) but negatively influences cassava (p = 0.00013) and rice (p = 0.050) yields. These results could inform the development of effective adaptation strategies tailored to this environment, helping to maintain and increase food production in the context of climate change.