For generations, Arab nomads in Darfur enjoyed a symbiotic relationship with their farming non-Arab neighbors. As the seasons changed, the nomads would bring their livestock from the arid north to the greener lands to the south during the dry season and then lead them back north during the rainy season. The non-Arabs, who came from several different ethnic groups, would allow the nomads to graze camels, sheep and goats on their farmlands, and in exchange the livestock would provide fertilizer for the farmers' crops.
That relationship, however, began to change about 75 years ago. And today, what had once been a convenient alliance between nomads and farmers has exploded into a bloody war between Darfur's Arabs and ethnic African tribes.
While many blame the bloodshed on political or ethnic divisions, others say climate change lies at the root of the devastation. "It is no accident that the violence in Darfur erupted during the drought," U.N. Secretary-General Ban Ki-moon said. "Until then, Arab nomadic herders had lived amicably with settled farmers."
Most people use "a convenient military and political shorthand" to describe Darfur as an ethnic conflict between Arab militias fighting black rebels and farmers, Ban explained. And, while the conflict involves a complex set of social and political causes, it "began as an ecological crisis, arising at least in part from climate change," he said.
According to the U. N., average precipitation in Sudan has declined 40 percent since the early 1980s. Signs of desertification began emerging as far back as the 1930s. A lake in El-Fashir in northern Darfur reached its lowest water level in 1938, after which wells had to be drilled to tap into underground water supplies. Villages in northern Darfur increasingly were evacuated because of disappearing water supplies.
In the 1980s a severe drought and famine made the northern areas nearly impossible to cultivate, forcing nomadic tribes to migrate even further south and increasingly encroach upon their farming neighbors' more fertile lands. To prevent damage from the nomad's passing herds, the farmers began to fence off their shrinking fertile plots. Violent land disputes grew more and more common.
"Interestingly, most of the Arab tribes who have their own land rights did not join the government's fight," said David Mozersky, the International Crisis Group's project director for the Horn of Africa.
A new report by the European Commission predicts that increasing drought and land overuse in North Africa and the Sahel — the semi-arid swath of land stretching from the Atlantic Ocean to the Horn of Africa — could destroy 75 percent of the region's arable land. As land and water resources disappear, the report said, such violent conflicts will increase around the world.
"Already today, climate change is having a major impact on the conflict in and around Darfur," the report said.
Economist Jeffrey Sachs, director of the Earth Institute at Columbia University, said Darfur is an example of the conflicts that increasingly will erupt because of climate change.
"What some regard as the arc of Islamic instability, across the Sahel, the Horn of Africa, Yemen, Iraq, Pakistan and Afghanistan, is more accurately an arc of hunger, population pressures, water stress, growing food insecurity and a pervasive lack of jobs," Sachs wrote earlier this year, using Darfur as an example of a conflict sparked by climate change.
But others say climate change is just an excuse used by the Sudanese government to relieve itself of responsibility. Politics is the real cause of the bloodshed in Darfur, many say, with President Omar Hassan al-Bashir's government bearing full blame for the ongoing violence.
"Jeffrey Sachs and Ban Ki-moon said it's essentially environmental. How dare they?" says Gillian Lusk, associate editor of the London-based newsletter Africa Confidential. "The essential issue is the Sudan government went in there and killed people." And any attempts "to turn it into a primary ethnic or environment issue are dangerous."
Still, many international leaders say Darfur is a warning sign of growing environmental degradation. "Climate change is already having a considerable impact on security," French President Nicolas Sarkozy told an international governmental conference in April. "If we keep going down this path, climate change will encourage the immigration of people with nothing towards areas where the population does have something, and the Darfur crisis will be only one crisis among dozens."