World leaders must promote effective land use methods to mitigate drought, says Luc Gnacadja of the UN Convention to Combat Desertification.
Severe droughts in Africa are a stark reminder of global unfairness. About 13 million people still struggle to have enough food in the Horn of Africa, and about the same number, most of them children, suffer from hunger in the Sahel region, which stretches across Africa below the Sahara.
Droughts now hit these parts of Sub-Saharan Africa more frequently than the usual ten-year cycle, and more severely. And people living there are the least responsible for this climatic change.
Last year, the response of the international community to the Horn of Africa crisis was catastrophically late and slow. Tens of thousands of people may have been rescued if we had not waited for the food crisis across East Africa to escalate into famine in Somalia.
To make things worse, humanitarian relief eventually leaves communities that depend on agriculture even more vulnerable to the next drought. Food aid disrupts local markets farmers lose income and a major incentive to grow crops when local people can get food for free.
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Now, the latest reports from early warning systems predict a crisis in both the Horn of Africa and Sahel again this year, when they have not yet recovered from the 2010 and 2011 droughts.  The question is, what are we going to do about it?
Protect and thrive
Farmers in the Maradi and Zinder regions of Niger know what to do. During the past 20 years they have protected trees on some five million hectares of farmland. Where they had no trees or only a few per hectare, they now have up to 120. These trees not only improve soil fertility but also provide about a million households with fodder, fruit and firewood.
A recent survey shows that the farmers who preserve trees are able to cope better with drought than other farmers in the same area.  Some of them even produced a modest cereal surplus in 2011.
This is just one example of highly successful sustainable land management on a grassroots level. Another is Yacouba Sawadogo, a farmer in Burkina Faso who featured in the documentary film, The Man Who Stopped the Desert. He has combined tree and crop planting techniques to turn the barren land in his village into a 15 hectare cultivated forest within three decades. 
We should not wait until the next food crisis emerges we need to disseminate this experience and scale it up to national and regional levels.
Drought is predictable. The tools and knowledge farmers need to cope with it are already there. What is missing is the political will and the lack of awareness about existing, sustainable land-use practices.
First steps are local
The first step is to empower local communities and foster farmer-to-farmer communication.
In 2004, the International Fund for Agricultural Development helped to create the first village committee in the Aguie district of the Maradi region in Niger to monitor regreening activities. The initiative is recognised at a national level, prompting the establishment of similar committees in neighbouring villages.
Today, these committees regularly meet to share experience in land management and protect trees from theft.
Then in 2008, several farmers from Senegal visited re-greened areas in Niger. On their return, they used what they learned to protect young trees on their farmland on about 40,000 hectares. Local authorities should encourage such experience sharing.
These successes should be communicated by local, national and international media especially radio, which is the most accessible medium for farmers across Africa.
National and international strategy
But strategies that work on the level of individual farmers are not enough. We need to make sure that each drought-prone country has a national drought policy, based on the principles of early warning, preparedness, risk management and response. This effort is led by the UN Convention to Combat Desertification and the World Meteorological Organization.
Such policies would embrace insurance schemes, for example, allowing farmers and herders affected by drought to receive state subsidies.
Most importantly, we should empower smallholder farmers to become 'champions' in the race against the disastrous effects of climate change. In most African countries, the land that local people have been cultivating for generations is legally owned by the government. But farmers will preserve their trees if they have clearly defined rights to them. So governments in Africa need to recognise these rights in forestry and agriculture laws.
We know from numerous studies that building long-term resilience is much more cost-effective than ad-hoc crisis response. Still, it seems easier for donors to justify spending money to feed a starving child rather than supporting his or her father to grow enough crops.
With the global community discussing the green economy and sustainable development in the UN Conference on Sustainable Development (Rio+20), it is unthinkable that we would continue standing by and allow tens of thousands of people to die of hunger.
We should act at local, national and global levels to give farmers the lead, and promote sustainable land use and re-greening initiatives.
The Rio+20 summit should make this a top priority. It is essential to averting the next food crisis in Africa, and meeting the global challenge of feeding nine billion people by 2050.
Luc Gnacadja is executive secretary of the UN Convention to Combat Desertification (UNCCD), which promotes a global response to desertification, land degradation and drought.
This article is part of our coverage on Science at Rio+20.