A study using 31 climate models projects more frequent and longer droughts in Africa’s Mediterranean region, southern Africa and Madagascar as the world warms, while central Africa shows the opposite pattern. The authors caution that models disagree over changes in intensity. These are projections under different scenarios, not observations of events that have already occurred.
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Drought patterns differ across Africa
The researchers compared simulations from 31 climate models at several levels of global warming. Their drought index combines rainfall with the atmosphere’s demand for moisture, so a dry signal is not simply a count of rainless days. Mediterranean Africa, southern Africa and Madagascar generally show more frequent and longer droughts in the projections; central Africa shows a contrasting decrease. The pattern varies in magnitude across emissions scenarios and warming levels.[1]
Climate models disagree on intensity
The paper also examines how the moisture budget changes during drought. Different processes matter in different regions: the analysis links southern Africa’s drying in part to lower evaporation, while circulation changes contribute in Madagascar. Model disagreement is substantial, especially for drought intensity, and accounts for a large share of projection uncertainty. Population and economic exposure estimates depend on scenarios and should not be read as losses already measured. The results describe possible futures rather than a single forecast for every locality.[1]
Drought signals emerge at different times
The researchers also estimated when a projected change becomes distinguishable from natural variability. Their analysis found that signals in drought frequency and intensity can emerge earlier than the signal in duration. Differences between climate models account for more than 60 percent of projection uncertainty in some assessments, so the timing should not be read as a precise date for every place.[1]
