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Abstract

Southern Africa has been identified as one of the hotspot areas of climate extremes
increasing, at the same time many communities in the region are dependent on rain-fed
agriculture, which is vulnerable to these rainfall and temperature extremes. The aimof this
study is to understand changes in extreme indices during the agricultural season under
climate change and how that affect the modeling of maize suitability in Southern Africa.
We analyze the changes in rainfall and its extreme indices (consecutive dry days, heavy
rain events and prolonged rainfall events), and temperature and its extreme indices (hot
night temperatures, hot day temperatures and frequency of very hot days) from the past
(1986–2014) to the future (2036–2064) and integrate these into a maize suitability model.
Temperature extremes are projected to increase in both duration and intensity, particularly
in the eastern parts of the region. Also, consecutive dry days are projected to increase
over larger areas during the agricultural season, while rainfall will be less in sums, heavier
in intensity and less prolonged in duration. Including extreme climate indices in maize
suitabilitymodeling improves the efficiency of themaize suitabilitymodel and showsmore
severe changes in maize suitability over Southern Africa than using season-long climatic
variables. We conclude that changes in climate extremes will increase and complicate
the livelihood-climate nexus in Southern Africa in the future, and therefore, a set of
comprehensive adaptation options for the agricultural sector are needed. These include
the use of heat, drought and high-intensity rainfall tolerant maize varieties, irrigation
and/or soil water conservation techniques, and in some cases switching from maize to
other crops.