Climate change models find staple crops face ruin on up to 1 million square km of African farmland

June 3, 2009

A new study by researchers from the Nairobi-based International Livestock Research Institute (ILRI) and the United Kingdom's Waen Associates has found that by 2050, hotter conditions, coupled with shifting rainfall patterns, could make anywhere from 500,000 to one million square kilometers of marginal African farmland no longer able to support even a subsistence level of food crops. However, the land, on which some 20 to 35 million people currently live, may still support livestock.

Boosting could be an attractive alternative for millions of poor farmers across Africa who, in the coming decades, could find that climate change has rendered their lands unsuitable for crop cultivation yet still viable for raising animals, according to the study that appears this week in a special edition of the journal and Policy.

"Livestock, particularly animals that are known to be tolerant of heat and , can survive in conditions that are far more severe than what crops can tolerate," said Philip Thornton, an ILRI scientist and one of the paper's co-authors. "Livestock can provide poor households with a buffer against the risk of climate change and, allow them to take advantage of the increasing demand for animal products in Africa."

"Any increase in livestock must be managed sustainably," said Carlos Seré, Director General of ILRI, which is one of 15 research centers supported by the Consultative Group on International Agricultural Research (CGIAR). "But our research shows there are many areas in Africa where over the next few decades climate vulnerability coupled with market demand for animal products will prompt many farming communities to add more livestock to their agriculture systems and we should prepare now for this inevitability. "

The analysis is part of a range of studies published in the journal that emerged from an April 2008 conference at Oxford University on food security and environmental change. The publication coincides with a meeting this week in Bonn in which experts from around the world will consider how a new global accord on climate change can offer adaptation strategies for the rural poor.

Thornton and his colleague, Peter Jones of Waen Associates in the UK, sought to identify farm-dependent areas of Africa that might be most vulnerable to the effects of climate change. They focused on what are considered "marginal lands," arid and semi-arid regions of West, East and southern Africa where, for example, scant precipitation already routinely causes crops to fail in one out of every six (or fewer) growing seasons.

The researchers then considered the impact of climate change in these regions and found that even in situations where climate change is moderated somewhat by global reductions in carbon emissions, a large number of farmers most likely will still face a considerable deterioration in growing conditions. The key measure was whether climate change under two widely used climate models—which offer projections based on high and low greenhouse-gas emission scenarios—would cause the number of "reliable crop growing days" to drop below 90 days between 2000 and 2050.

They concluded that under scenarios in which carbon emissions remain high, the number of reliable growing days would drop below 90 for almost one million square kilometers of marginal growing lands in Africa. Assuming a "lower emission scenario," they project about 500,000 square kilometers would fail to reach the 90-day mark.

The researchers warn that if reliable growing periods drop below 90 days in these areas, "maize cultivation, already marginal, will basically no longer be possible as a normal agricultural activity." They continue, saying that in some places, rain could become so scarce that "even the drought-tolerant crops such as millet" will be difficult to grow. They say that in these conditions, livestock could be the key to keeping food on the table and for earning income as well.

In particular, according to the study, livestock could provide a significant income boost for farmers trying to survive on marginal lands that are within a day's travel time of one of Africa's urban populations, where a growing demand for meat and dairy products could provide lucrative markets.

Thornton and Jones pointed out that looking to livestock as a bulwark against challenging climates is not a novel idea. They note that across Africa "livestock have proven to be a crucial coping mechanism for poor people who are trying to survive in difficult environmental conditions."

Thornton said the goal of the research is ultimately to use climate change projections to pinpoint specific areas in Africa—each of which may be relatively small in size—where it is appropriate to promote livestock ownership on small-holder farms and to help farmers deal with the risks inherent in such operations. But he said employing this kind of research to direct policy decisions would benefit greatly from obtaining better data at the local level, including data projecting what local temperatures and rainfall patterns may look like in the future.

However, he and Jones acknowledge that "there is currently a mismatch between the kind of localised climate change impact information that is urgently needed, and what can objectively be supplied."

For example, even at large, regional levels, while there is consensus that temperatures will rise significantly, different climate models don't always agree as to how climate change may affect rainfall amounts and patterns in some parts of Africa. But they said investments in generating such details are warranted given the potential to bring new levels of precision and efficiency to aid programs focused on alleviating poverty among the rural poor in Africa, most of whom depend on small holder farms for food and income.

The researchers also observe that better data will inevitably show what some may be reluctant to see, but which must be confronted nonetheless: that in certain parts of Africa where growing conditions already are difficult, there are simply limits to what can be done to help farmers adapt to . Harsh reality though it may be, Thornton and Jones said it is important for development agencies and governments alike to understand that as climate conditions become more inhospitable to agriculture in some places, there may be "a point at which households and farming systems become so stressed that there are few alternatives to an exit from farming."

Source: International Livestock Research Institute

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3 / 5 (4) Jun 03, 2009
Lies, Damned Lies, and Computer Models...
3 / 5 (2) Jun 04, 2009
I see they still only presume the climate can only get warmer. Do they factor in that inceased CO2 makes crops more resistant to drought and have a better yield?
They concluded that under scenarios in which carbon emissions remain high,

The use of the word scenarios says it all. { outline or synopsis of a dramatic work, 2.a screen play, account or synopsis of a projected course of action}
This is not a projected course of action, so 1 or 2 must apply,so the screen play must be science fiction.
3.7 / 5 (3) Jun 04, 2009
More hype from the global warming cultists. They obviously didn't examine areas that may benefit from increased warming. The name of the magazine says it all: Environmental Sciency and Policy. Individuals can adapt to changes - getting government involved will result in one group using government to take from everyone else. And they are already succeeding in getting grant money at taxpayers expense. I say let's defund all this research and save the money. The cultists need to get jobs that contribute to society rather than leech off it.
5 / 5 (2) Jun 04, 2009
Anybody else notice the surge (trend) in politically leaning "articles" I mean more than usual.

I'm gonna go look for a real science new sight. I have had enough. see ya
3.7 / 5 (3) Jun 04, 2009
It's not the climate that causes disaster in Africa, it's the behavior of the people. I really don't feel I'm responsible personally or even nationally to provide a safety net for a population that reproduces beyond their ability to support, and who cannot figure out how to live on the land they have.

There's all sorts of NGO's who feel we need to support African nations who don't seem to be geting the basic lessons of civilization. If you want to do it with private money, go right ahead. But to tangentially blame developed nations GHG emissions for their regular, repeating environmental collapses is ridiculous.

In the US we grow hundreds of thousands of acres using marginal land that would otherwise be unarable, and we can do it because we don't behave like they do in Africa. What is the real cause of poverty and chaos in a society? It's not the weather.
5 / 5 (1) Jun 06, 2009
We don't behave like they do in Africa. We in the U.S. and Canada force, through the global economic system, about 20 thousand African children to die of starvation everyday. You could even call it murder. Nations around the world have enough food and the means to get it there. Most of these nations with starving children grow crops for export to pay off debts. For most of humans age of civilization children have been left to die to make the price of grain or something look good on paper. A loss of any farmland on earth is really a non issue, as it us who decides who eats and who doesn't these days. Probably always have and always will.
not rated yet Jun 07, 2009

I think you may have your causality confused. You're right, WE have an abundance of food because WE grow it and live in a peaceful and stable society. Tribal nations who live in desert wastelands and are constantly fighting amongst themselves are going to starve to death. If a tribesman has 7 children to feed in such conditions, what do you think will happen?

If you are saying these tribal settlements are growing crops to pay off international debts and they are starving because the west is taking their produce away, then you are being silly. Western nations exploit labor and resources; they have absolutely no interest in vegetables and cattle from these places. Everywhere capitalism has built factories, mines, and oil fields in Africa the income and living standard of the people has gone up. The problem isn't Western investment in Africa, it's criminal misbehavior of African leaders and corruption of corporate interests. Evil occurs of evil behavior, not because of one people's wealth on the other side of the world.

While it's true that business interests in Africa have proven to be destablizing and corrupt, it's important to realize the the USA and Canada are very late to that sort of game. It's Europe and the UK who taught who wrote the book on colonial exploitation.

There are some nations in Africa who do quite well, and there are others who don't seem to get it. The ones with problems have behavior patterns that can be identified going back for centuries. The ones who have enough to eat have traits that have made them more successful.

Through private and semi-public charity work people from the West have worked in Africa for decades. They find people who lack all understanding, can't build wells for themselves, cannot irrigate, and do not seem to be able to develop social infrastructure independently. They are failures not because they are poor, not because of our abundance, but because they lack the virtues necessary to succeed.

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