Excerpts from the Oxfam report “Suffering the Science: Climate Change, People and Poverty”:
As a consequence of climate change, there has already been significant change in the types of crop that people grow, because in the tropics it takes only 1°C of average temperature change to begin to alter the suitability of some key crops. Reduced crop yields become all the more grave when combined with large population growth and low economic prospects, which threaten disaster for many countries.
One study combines all these factors to predict which African countries will be hardest hit by climate change in the future: it puts Mozambique, the Democratic Republic of Congo (DRC), and Tanzania at the top of that list by 2030.
Poor farmers often have to gamble when deciding what might be better crops to shift to. In countries where rainfall patterns and cyclical dry spells are becoming increasingly unpredictable and extreme, even the ‘common farming sense’ of swapping from one crop to another to find a successful one can backfire.
Unfair shares
Across the world, the effect of climatic changes on agriculture will be grossly unbalanced. Essentially, the further a person lives from the Equator, the better their prospects of being fed – and that’s not just because the richer and less populated countries tend to lie in the higher latitudes of the Northern hemisphere, where precipitation will increase and winters will get warmer.
Wheat production should rise considerably in northern Europe and Canada. Meanwhile on the Indo-Gangetic plain, where 15 per cent of the world’s wheat is grown, production will shrink by more than half by 2050. This change alone will threaten the food security of 200 million people. The Mediterranean countries and some parts of the USA are similarly threatened.
Adapting to these changes will be easier in sophisticated and richer agricultural economies. According to one forecast, US agricultural profits will rise overall by $1.3 billion, or 4 per cent, per annum because of climate change, though some states, including California, will see substantial declines.32 Meanwhile sub-Saharan Africa will lose $2 billion per annum as the viability of just one crop – maize – declines.
Government scientists in South Africa are now advising that countries in the region should prepare to see a 50 per cent drop in productivity of all cereals by 2080.
Broadly, the current scientific predictions on the hunger threat can be summarised as follows:
- South Asia (the world’s most populous region), Southern Africa, and the sub-Saharan region will see severe threats to food supply, mainly because of the threat to their staple crops, although there are other hazards of higher temperatures and shifting rainfall patterns…
- The livelihoods of millions of African pastoralists, responsible for some of the world’s most efficient and ecologically-friendly meat and dairy production, are under serious threat.
- In the mixed cultivation areas of Africa where pastoralists and agriculturalists exist side by side, ‘season failures’ are expected to extend from one year in six to one in three.
- Disturbing new research is emerging on how a degree or two of temperature rise makes outdoor labour very difficult, and in some cases impossible and even life-threatening, during the hottest months of the year, which are the harvest season for some crops…
- All low-lying coastal areas and islands are at risk because of sea- level rises and storms, as are populations where seafood is a protein source or a means of livelihood. Climate change is modifying the distribution and productivity of fisheries and altering food webs…
Maize
Maize – or corn as it is known in some countries – is one of the world’s four most important food crops. It is the staple food for more than a quarter of a billion East Africans, and is also a hugely important animal feed across the world. Maize is particularly vulnerable to heat changes and to ‘water stress’.
As one crop scientist puts it, ‘When you look at the graph, under even small average heat rises, the [production] line for maize just goes straight down.’
Drought damages maize especially at its seedling stage, when the farmer will find the leaves ‘rolled’ and the plant looking tired. There may be a decreased yield or no maize ears at all. A severe problem may mean no crop that year.
In one of the best-documented heat waves of modern times, the 2003 event in western Europe, when temperatures rose up to 6ºC above average, maize production dropped by 20 per cent in France, and by up to 36 per cent in parts of Italy.47 Other staples such as wheat were badly affected as well.
Even under milder scenarios, the viability of maize as a staple crop is under serious challenge in a range of Southern African countries, including Mozambique, Tanzania, and Zambia. The suitability of maize as a crop is forecast to drop by 15 per cent or more by 2020 in much of sub-Saharan Africa and in most of India. One estimate puts the loss to Africa at $2 billion a year.
Crop substitution – not so simple
There are alternative crops that may survive better. For example, millet and sorghum are suited to cultivation in parts of Southern Africa as temperatures rise and rainfall decreases. With the aid of Oxfam and government agencies, farmers are already trying different species in a number of countries. Some populations could, for example, substitute cassava or yam for carbohydrates…
However, the social costs of trying to adapt whole agricultural systems to new crops, or the mass moving of entire farming populations, are considerable. It will take ‘a pretty radical upheaval’, says one expert…
Export crops
Crops of course are not grown just for general consumption in the country of origin, but are also grown for export. Due to climate change effects, cash crops – which are crucial to many equatorial countries – are likely to suffer, so affecting income generation.
Sign up for free AllAfrica Newsletters
Get the latest in African news delivered straight to your inbox
The regions most suitable for coffee production will shift; coffee yields and quality are likely to change with small temperature increases (1– 2°C). Such intensively grown crops are likely to be affected by more diseases and pests.
Tea production, which employs 500,000 people in Kenya, with perhaps two million more people dependent on their income, is also highly sensitive to changes in heat and water.
The locust bean tree
The bright red flower and protein-rich seeds of the locust bean tree are valued by people across West and Central Africa, from Senegal and Guinea to Congo and Chad.
The fruit pulp and seeds are rich in sugars, amino acids, and vitamins. They are good food for both humans and animals. The trees also provide fuel, building materials, and medicine. Even the twigs are used as toothbrushes. The broad branches of this beautiful tree also provide shade for growing vegetables and play an important role in soil ecology.
But drought in recent decades has caused the locust bean tree to retreat swiftly from the northern parts of the Sahel countries. Moussa Ouedraogo, a scientist at the Centre National de Semences Forestières in Burkina Faso, has run studies of the locust bean tree in the field. He says that urgent action is needed to develop improved seeds so that the tree can adapt to the coming climate change.
