Food Security and Climate Change

Submitted by Sukaina Bharwani | published 25th Mar 2011 | last updated 30th Mar 2011

Agricultural production, including access to food, in many African countries and regions, is projected to be severely compromised by climate variability and change. The area suitable for agriculture, the length of growing seasons and yield potential, particularly along the margins of semi-arid and arid areas, are expected to decrease. This would further adversely affect food security on the continent. In some countries, yields from rain-fed agriculture could be reduced by up to 50% by 2020. Many of these countries already experience malnutrition, with 25% or more of children under 5 moderately or severely underweight. The positive impact of increasing concentrations of carbon dioxide that speeds up plant growth, experienced in temperate regions such as Europe, is not expected to benefit Africa. Fires, pests and pathogen outbreaks, controlled in part by climate variables, will have an additional negative impact on food production.

Local food supplies are projected to be negatively affected by decreasing fisheries resources in large lakes due to rising water temperatures, which may be exacerbated by continued over-fishing.

Wild foods, that many poor households rely on, particularly when there are few other food sources, are expected to change in their distribution. In a study in sub-Saharan African, of the 5,000 plants species examined, it is predicted that 81%–97% of the plant species’ suitable habitats will decrease in size or shift due to climate change. By 2085, between 25% and 42% of the species’ habitats are expected to be lost altogether. The implications of these changes are particularly great among communities that use these plants as food sources or for plant-based medicines.

Extreme events, such as droughts and floods, impact on crop and livestock productivity as well as impacting on access to food. If infrastructure is impacted by heat stress on roads or through increasing flood events that destroy bridges, roads and railways, distribution of food is hampered. Destroyed infrastructure, from floods, also impedes people’s access to markets to sell or purchase food.

Food utilization, a key component of food security, refers to the use of food and how a person is able to secure the nutrients and quality of food needed. As climate changes, so the types of seed cultivars and varieties that can be grown change so that they are more appropriately suited to the climate. This has implications for what people eat. For example, in southern Africa maize is the staple crop. However, sorghum fairs better if there is less rainfall. Yet, many people prefer to eat maize than sorghum and so continue to plant maize despite poor yields. If other produce that is easier to grow in a different climate becomes cheaper, people may change their food basket or it could result in people spending a greater percentage of their income on food if prices increase. In addition, people with certain diseases require improved nutrients to help fight disease, such as in the case of HIV/AIDS. Changing food security linked to climate change, can therefore impact on nutrition security of ill household members.

Gina Ziervogel