**1. Introduction**

The world population is expected to grow by more than one-third, that is, 2.3 billion people, between the years 2009 and 2050. This growth is slower than the one seen in the past four decades, where the population grew by more than 90% (3.3 billion people). Nearly all the predicted growth is to take place in the developing world, predominantly in Africa. The fastest growth (+114%) is forecasted for sub-Saharan Africa and the slowest growth (+13%) for East and Southeast Asia [1].

Food security exists when all people in a society have adequate food for an active, healthy life at all times [2]. As a broad term, 'food security' is defined by: (1) the availability of safe and nutritious food and (2) a guaranteed capability to procure and acquire food of good quality in a socially acceptable way. Food insecurity on the other hand occurs when basic healthy food is not easily accessible, and poor households struggle to secure enough food for their nutritional needs [3]. Food insecurity has been identified as a global crisis [4].

Food insecurity is a major challenge in African countries where the rate at which the population grows far exceeds both the quantity and quality of food required to sustain the population (**Figure 1**). It is reported that 204 million of the 814 million undernourished people in the world live in sub-Saharan Africa [3]. The root causes of hunger are poverty and poor food distribution. The majority of poor households in sub-Saharan Africa are struggling to access high national and healthy food. Food insecurity and hunger in sub-Saharan Africa are caused by agricultural policy uncertain such as land reform and expropriation land without compensation. Increased food requirements from a growing world population will only escalate existing food

**Figure 1.** *Population projections. Source: [1].*

security problems. The United Nations estimates that by 2050, 86% of the world's population living in extreme poverty will be concentrated in sub-Saharan Africa [1]. And in order to ensure food security in the future, current food production levels will need to be increased by at least 70% [1].

Projected climate change and unexpected extreme weather events will worsen the fragile agricultural systems, negatively affecting the natural resource base, particularly in places prone to soil degradation, water scarcity and desertification [5]. The sub-Saharan Africa is well known for relying heavy on rainfed agriculture, however, due to threats posed by extreme climatic events, high climate variability and change, the majority of the climate sensitive sectors are struggling to cope and adapt to challenges posed this natural vagaries. The general effect of climate change on agriculture will differ between different geographic regions, and it will still be difficult for farmers to plan and manage production while preventing crop losses or outbreaks of pests and diseases.
