What’s Behind the Harmattan?

During the winter months of the northern hemisphere, the atmospheric circulation patterns shift, pushing warm, moist air away from the inter-tropical convergence zone towards the Gulf of Guinea. This leaves a dry, dusty current—the Harmattan—dominant across most of West Africa. While it can make the air clear, the visibility comes at a cost.

The Drying Effect of Harmattan

With their origins in the high altitudes, Harmattan air masses are characterized by stark temperature fluctuations—cool at night and exceedingly hot during the day. This phenomenon creates a stable atmosphere that allows for intensified winds, especially during early mornings. This result is a hazardous combination for dry, easily erodible soils, particularly in regions like the Bodélé Depression, recognized as a major source of desert dust particles.

Health Implications of Harmattan Winds

As it sweeps across populated areas, the Harmattan carries more than just dust; it transports microbes and parasites that can exacerbate various health conditions. Respiratory problems such as bronchitis, pneumonia, and asthma are on the rise due to degraded air quality. The connection between the Harmattan and infectious diseases like influenza and tuberculosis (TB) is particularly alarming, with studies showing that the exposure to these dry, dust-laden winds can lead to higher rates of infant mortality—up to 24% in recent years, as fine dust particle concentrations have surged.

Combating the Harmattan Threat

To combat the effect of Harmattan winds, robust research and monitoring systems are being implemented. European programs like Copernicus are aiding in the documentation and prediction of dust plumes. As the Harmattan season draws to a close in April, air quality in the region typically deteriorates, exacerbating respiratory issues during subsequent heatwaves.