If the rains fail, so could the cocoa beans

Yesterday many of us overindulged in chocolate, but Easter is not the only time we munch our way through mounds of cocoa-based treats. Globally, chocolate consumption is on the rise and the majority of this demand is met by cocoa farmers in southern West Africa. Now there are concerns that pollution in the region could interfere with the West African monsoon, potentially drying up the world’s main supply of cocoa beans. Like many other cities in southern West Africa, Abidjan on the Côte d’Ivoire, is growing fast, and with the expansion comes increasing air pollution. So will these extra particulates and gases change the weather? Already scientists have shown that the increased emissions of sulphates over India has led to more sunlight being reflected back up to space. Consequently land in India has remained cooler, reducing the land-sea contrast in temperature, resulting in diminished Indian monsoon rainfall in recent years. Could West Africa be about to suffer a similar fate? The West African monsoon, which brings moist air from the Gulf of Guinea during northern hemisphere summer, is already very variable already, but scientists are now concerned that the extra pollution might really mess it up. This summer an EU funded project – Dynamics-Aerosols-Chemistry-Cloud Interaction in West Africa – is flying scientists into the clouds to take measurements across the region, and assess what impact pollution is having on the monsoon. If emissions from cities like Abidjan are damping down the West African monsoon then chocoholics may have to pay significantly more for their favourite sweet treat, until the skies are cleaned and optimal chocolate-weather returns.