Zimbabweans, or 16 per cent of the population, would need food aid by next March.
The drought has also reduced power generation at hydroelectricity plants after water levels at dams fell, forcing mines to reduce output in neighbouring Zambia, Africa’s second-biggest copper producer.
In west Africa, a lack of rainfall across Ghana’s cocoa belt has raised fears that the world’s second-largest grower could face another poor crop.
In Ethiopia, 4.5 million people need food aid because of El Nino and long-term climate change, according to UN agencies.
Mixed results
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However, El Nino typically brings increased rains to Africa’s east. Enhanced rainfall will boost farming, even though farmers need to be aware of the prevalence of diseases as high moisture levels may cause post-harvest losses.
Recent El Nino events brought floods to Kenya in 1997-98 and 2006-07, resulting in losses of lives, harvests and livestock, as well as infrastructure damage and outbreaks of hunger and disease.