Smallholder farmers in Burkina Faso are increasingly challenged by the uncertainty and variability of weather that climate change causes , . Since crops are predominantly rainfed, they depend on water availability from precipitation and are prone to drought. However, the length and intensity of the rainy season is becoming increasingly unpredictable and the use of irrigation facilities remains limited due to high costs of initial investment, problems regarding the maintenance of the equipment and harsh environmental conditions . Currently, only 0.5 % of the total national crop land and 27 % of the estimated irrigation potential of 233 500 ha are irrigated , . Especially in northern Burkina Faso, soils are poor in nutrients, sandy and shallow, which makes them vulnerable to drying, erosion and flooding .
Crop land exposure to drought
Currently, the high uncertainty of projections regarding water availability (Figure 9) translates into high uncertainty of drought projections (Figure 10). According to the median over all models employed for this analysis, the national crop land area exposed to at least one drought per year will hardly change in response to global warming. However, there are models that project a strong increase in drought exposure. Under RCP6.0, the likely range of drought exposure of the national crop land area per year widens from 0.07–3.8 % in 2000 to 0.04–16.0 % in 2080. The very likely range widens from 0.01–12.0 % in 2000 to 0.01–29.0 % in 2080. This means that some models project up to a fourfold increase in drought exposure over this time period, while others project no change.
Crop yield projections
Climate change will have a negative impact on yields of maize, millet and sorghum (Figure 11). While maize is sensitive to hot temperatures above 35 °C, millet and sorghum tolerate hot temperatures and dry periods better . Still, model results indicate a negative yield trend for all three crops under both RCPs with a stronger decrease under RCP6.0. Compared to the year 2000, amounts are projected to decline by 12.0 % for maize and 7.5 % for millet and sorghum by 2080 under RCP6.0. Under RCP2.6, yields of maize are projected to decline by 8.4 % and yields of millet and sorghum by 5.2 %, whereas yields of cow peas and rice are projected to gain from climate change. Under RCP6.0, projections show an increase in yield by 16.2 % for cow peas and 27.0 % for rice by 2080 relative to the year 2000. An explanation for the positive results under RCP6.0 is that cow peas and rice are so-called C3 plants, which follow a different metabolic pathway than maize, millet and sorghum (C4 plants), and benefit more from the CO2 fertilisation effect under higher concentration pathways. Yields of groundnuts are projected to decrease under RCP2.6 and slightly increase under RCP6.0. The decrease under RCP2.6 can be explained by non-temperature related parameters such as changes in precipitation, while the increase under RCP6.0 can be explained by the CO2 fertilisation effect.
Overall, adaptation strategies such as switching to improved varieties in climate change sensitive crops should be considered, yet carefully weighed against adverse outcomes, such as a resulting decline of agro-biodiversity and loss of local crop types.
 B. Barbier, H. Yacouba, H. Karambiri, M. Zoromé, and B. Somé, “Human Vulnerability to Climate Variability in the Sahel: Farmers’ Adaptation Strategies in Northern Burkina Faso,” Environ. Manage., vol. 43, no. 5, pp. 790–803, 2009.
 B. Sarr et al., “Adapting to Climate Variability and Change in Smallholder Farming Communities: A Case Study From Burkina Faso, Chad and Niger (CVCADAPT),” J. Agric. Ext. Rural Dev., vol. 7, no. 1, pp. 16–27, 2015.
 J. Wanvoeke, J. P. Venot, C. De Fraiture, and M. Zwarteveen, “Smallholder Drip Irrigation in Burkina Faso: The Role of Development Brokers,” J. Dev. Stud., vol. 52, no. 7, pp. 1019–1033, 2016.
 R. E. Namara and H. Sally, “Proceedings of the Workshop on Irrigation in West Africa: Current Status and a View to the Future,” Colombo, Sri Lanka, 2014.
 USAID, “Country Profile: Property Rights and Resource Governance in Burkina Faso,” Washington, D.C., 2017.
 USAID, “Climate Risks in Food for Peace Geographies: Burkina Faso,” Washington, D.C., 2017.
 USAID, “Climate Risk in Food for Peace Geographies: Kenya,” Washington, D.C., 2019.