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Malawi is listed as a Low-Income Food-Deficit Country (LIFDC) by the United Nations (UN), with high levels of poverty, malnutrition, and undernutrition. The maize grown in the Central Region of Malawi represents approximately a quarter of the total Malawian population's calorie intake, is a large source of local income, and a significant contributor to the country's Gross Domestic Product (GDP). While maize has been shown to be more resilient to climatic changes than many other grain crops, the 2 predominantly rain-fed maize grown in Central Malawi has experienced many shocks from severe weather events in the past. Using the ensemble mean of 20 Regional Climate Models (RCMs), this study shows that temperatures in Central Malawi are projected to increase from the 1971-2000 baseline by between 1.4 and 1.6°C by 2035 and 1.9 and 2.5°C by 2055 under Representative Concentration Pathways (RCPs) 4.5 and 8.5 respectively, but precipitation projections are more uncertain. Using the UN Food and Agriculture Organization's (FAO) AquaCrop model, this study assesses the impact of future warming and three precipitation scenarios on two cultivars of maize planted on three separate dates in Central Malawi's summer planting season. The results indicate that if precipitation levels follow the ensemble average or maximum projection, then moving to a later planting date and a slower-developing cultivar may result in increasing yields compared to the baseline scenario. However, under a minimum precipitation projection, the results are less positive, with decreasing yields seen for both cultivars and all planting dates. The uncertainty around future precipitation therefore poses a significant risk of maladaptation and highlights the need for more robust precipitation projections in the area before climate model outputs are used as a primary driver for decision-making in Central Malawi's maize cultivation.

Malawi is one of the poorest countries in the world, with high levels of malnutrition and little domestic mycotoxin regulation. Domestically grown maize is the largest single source of calories in the country and a large contributor to the economy. This research uses Regional Climate Models (RCMs) to determine the climatic conditions in the three regions of Malawi (Northern, Central and Southern) in 2035 (2020–2049) and 2055 (2040–2069) as compared to the baseline climate of 1971–2000. This climatic data is then used as inputs to the Food and Agriculture Organization's (FAO) AquaCrop model to assess the impact on the growth cycle of two maize varieties grown in each region and sown at three different times during the planting season. Finally, AFLA-maize, a mechanistic model, is applied to determine the impact of these projected changes on the aflatoxin B1 (AFB1) contamination risk. We find that Malawi's climate is projected to get warmer (by 1–2.5°C) and drier (reduction of 0–4% in annual rainfall levels) in all regions, although some uncertainty remains around the changes in precipitation levels. These climatic changes are expected to shorten the growing season for maize, bringing the harvest date forward by between 10 and 25 days for the short-development variety and between 25 and 65 days for the long-development variety. These changes are also projected to make the pre-harvest conditions for Malawian maize more favorable for AFB1 contamination and risk maps for the studied conditions were drawn. Exceedances of EU safety thresholds are expected to be possible in all regions, with the risk of contamination moving northwards in a warming climate.

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