The intensifying Harmattan winds of Northern Ghana : implications for agriculture

Abstract

The Harmattan is a dry, dust-laden continental wind in West Africa which has its origin from the Sahara Desert. The season of Harmattan in Ghana takes place between November and March and traditionally, it has been considered a highly predictable seasonal event with very little analytical importance in the context of agricultural risk management. However, recent climatic and community reports in Northern Ghana suggest that the extent and duration of the Harmattan winds is rising with their longer persistence, higher dust concentrations, low humidity, and higher temperatures during dry periods. This creates an analytical research gap of the influence of the wind-driven, slow-onset climatic stressors on agricultural productivity in climate-sensitive regions. This paper discusses the growing intensity of the Harmattan winds in Northern Ghana and the impacts this has on agriculture, especially the Guinea and Sudan savannah regions where the system of rain-fed smallholder agriculture prevails. The study relies on the qualitative analysis based on climatic data provided by the Ghana Meteorological Agency (GMet), agricultural and institutional reports by national and international institutions, and peer-reviewed climate studies. Harmattan indicators are interpreted according to the time interval 2010- 2025. The existing reports show that there is obvious indication of increased duration of the Harmattan season, frequent temperature-humidity changes, and prolonged dust exposure. These atmospheric alterations are linked to soil moisture loss by winds, topsoil erosion during pre-planting, crop desiccation that does not depend on the rainfall failure, increasing irrigation expenses, and degradation of pastures. The analysis also reveals that the effects of the harmattan are analytically distinct, and these are not drought, but rather other physical processes and affect farming systems even when there are no extreme rainfall deficits. This paper will add to the literature on climate-agriculture by redefining the relationship between climatic risk and agriculture, instead of the narrow focus on rainfall-based models. The study also gives emphasis on the necessity of changing the mindset of the farmers, policy makers and early warning systems in Northern Ghana from rain-based to Harmattan related indicators including wind intensity, humidity suppression, dust exposure and evapotranspiration stress. It is necessary to incorporate them in agriculture planning and climate policy to increase the resilience of smallholder farmers in dryland areas, which are vulnerable to climate change.