ROME - Lake Chad was bigger than Israel less than 50 years ago. Today its surface area is les than a tenth of its earlier size, amid forecasts the lake could disappear altogether within 20 years.
Climate change and overuse have put one of Africa's mightiest lakes in mortal danger, and the livelihoods of the 30 million people who depend on its waters is hanging by a thread as a result.
An unprecedented crisis is looming that would create fresh hunger in a region already suffering grave food insecurity, and pose a massive threat to peace and stability, experts say.
"If Lake Chad dries up, 30 million people will have no means of a livelihood, and that is a big security problem because of growing competition for smaller quantities of water," Dr Abdullahi Umar Ganduje, executive secretary of the Lake Chad Basin Commission (LCBC) tells IPS in Rome.
"Poverty and hunger will increase. When there is no food to eat, there is bound to be violence."
The lake, which shrank 90 percent between 1963 and 2001 from 25,000 square kilometres to under 1,500, is bordered by Chad, Niger, Cameroon and Nigeria.
Four more countries, the Central African Republic, Algeria, Sudan and Libya, share the lake's hydrological basin and are therefore affected by its fortunes.
"Lake Chad has experienced shrinkage," Libyan leader Muammar Gaddafi said at November's World Food Security Summit at the United Nations Food and Agriculture Organisation (FAO) in Rome. "If it dries up, it will be a real disaster. I want to warn the world about this imminent disaster."
That disaster has already started. Villages that used to be thriving lakeside ports are now stranded miles from the water, and have been swallowed by the advancing Sahara desert. Fishers and farmers are struggling to survive.
"The dramatic situation is already taking place," Maher Salman, a technical officer with FAO's land and water division tells IPS. "It's clear that the consequences have started. There is outward migration. People are looking for water, so they leave the basin area."
Fishers have seen once massive catches frequently reduced to half-filled buckets. The FAO says the lake's fish production has fallen 60 percent, and the variety of fish caught has dramatically declined too.
Farmers who rely on lake waters for irrigation are having to move nearer to the water or abandon their activities. Lack of water has caused pasture lands to shrivel up and led to a serious shortage of animal feed, estimated at 46.5 percent in some areas in 2006, resulting in cattle deaths and plummeting livestock production.
This is the sort of situation former World Bank vice-president Ismail Serageldin was worried about in 1995 when he said that "the wars of the 20th century were fought over oil, and the wars of the next century will be about water" - a view echoed in reports by several organisations including the U.S. Central Intelligence Agency.
While some experts remain sceptical about the prospect of all-out wars being fought over water, there have been numerous reports of clashes between farmers and herds-people competing for productive land in the Lake Chad area.
Biodiversity too has been hit by the lake's retreat. So has the region's health situation.
"Due to the movement of people looking for food there is a high level of interaction, which complicates matters because of the high prevalence of HIV among Lake Chad inhabitants," says Ganduje. "The African Development Bank has come to our aid, and we are tackling this."
Little can be done at the regional level about climate change, which is attacking the lake on two fronts - reducing the rainfall that feeds it, and accelerating evaporation of its waters due to higher temperatures. Its shallowness for such a major water body makes it particularly vulnerable to these attacks.
It is a grim situation, but not a hopeless one. The other half of the problem, over-extraction, can be tackled locally.
"We are optimistic," says Ganduje. "We are regulating the use of Lake Chad water. We are drawing up a charter so everyone has common rules and regulations in the use of water.
"We are also controlling activities on the tributaries to Lake Chad, such as the construction of dams and irrigation activities. We are controlling human behaviour in response to other factors that are outside of our control."
This confidence is justified in part by growing understanding of the need for a response.
"There is recognition of the need for new management strategies to be put into place," says Salman. "The most common conclusion of studies on the lake's shrinkage is that it is due to both human pressure on water resources and on climate change. A solution should be possible.
"There needs to be optimum use of the waters in each sector, up-scaling water conservation and small-scale agricultural technologies for more efficient irrigation. Awareness about use of the waters is important as well, so people cut down."
The LCBC also has high hopes of an ambitious plan to replenish the lake to its 1960s levels by diverting water from the Oubangui River, which is the major tributary to the Congo River.
"The feasibility study has started and a fund has been set up," says Ganduje. "The heads of state are confident of progress. If the feasibility study is positive, we believe we have the political support required."
The FAO says it does not have a position on whether the transfer project should go ahead, although it has called for very careful consideration of its impact, including that on the Congo River system. What it views as key is the presentation of concrete plans to save the lake, so donors can be badgered into committing to a cause that is crucial to millions of people .
"There is a strategic action plan for the sustainable development of Lake Chad, but to translate that into action we need an investment plan," says Salman. "We need more meetings of donors to get them to commit and make good those commitments through investment. The good news is that there is a consensus on the need for action."