Will climate change turn the Sahel green?

The Sahel region could go from one of the driest areas in the world to a very wet one in a couple of decades. That is one conclusion reached by a research paper just published by the Potsdam Institute for Climate research (Potsdam-Institut für Klimafolgenforschung). "What is new is the observation that there are some scenarios where you get not just a little more rain, but substantially more rain, and it may happen quite suddenly," Jacob Schewe, co-author of the new study, told DW.
This does not come as a surprise to Emmanuel Oladipo, professor of climatology at the University of Lagos, in Nigeria, who emphasized the high degree of volatility of the climate in the region."What appears to be happening now is that the system is tilting to what happened in the sixties. We are getting more rainfall than what we used to get." Data for the last hundred years, compiled by theJoint Institute for the Study of the Atmosphere and Ocean, in Washington, USA, show unusually high rainfall from 1950 to 1970. This was followed by years of drought until 1990. Rainfall then returned to almost the former average, although there is now a high variability annually. Nevertheless, experts like Schewe and Oladipo agree that in the last years, rain intensity has increased.

Too much of a good thing

On the surface, more rain seems like a good thing. It brings more water for domestic, agricultural and industrial use. There are some regions in central and western Sahel where increased rainfall has already come as a relief to the people and allowed ecosystems to make some recovery, Schewe said. But he cautioned that the prospect of a sudden and abrupt increase of downfall cannot be taken lightly: "People need to be able to prepare for it and all the consequences it would have. It doesn’t mean just more water on average. Another rainfall regime with a proper monsoon season could also bring more flooding, which can be challenging in many ways for the local population." 
The authors of the German study point out that it is not really possible to predict accurately if change will be abrupt or gradual. But if a shift does come, it will be "within our lifetime" and can be very sudden, Schewe said. 
This poses a huge challenge for the countries in the Sahel, which will have to prepare for all possible eventualities. Drought and climate change are only two of a range of serious problems afflicting the region, which faces a number of conflicts, including some driven by jihadist groups such as Boko Haram and al Qaeda in the Islamic Maghreb.

What to prepare for 

Pointing out that Nigeria already had some unusually heavy rain this year, climatologist Oladipo does not feel very optimistic that all urgent measures will put in place in time. "If the rainfall increases in intensity, then it may be ending up by doing more damage to the environment," Oladipo told DW. To counter negative consequences like flooding, infrastructures need to be built. The same applies to systems which would allow people to capture the water, and prevent it from washing away arable land.  
Thus, the natural vagaries of the climate, made worse by the emission of greenhouse gases, makes the job of those responsible for prevention at local and international levels very difficult. A measure of certainty might be welcome. But Schewe does not believe that putting a time frame on his predictions will help: "If I gave you a number, let’s say, a 30 percent likelihood for an abrupt rainfall regime change, what would you do with it? Would you then prepare for it, or say it’s too little or a lot?” Schewe said, adding: "We can only assess the risks, and there is a substantial risk here."According to Schewe, it is important to be "open to a range of outcomes, and you can’t bet on a single outcome."

Lack of infrastructures

But the Sahel countries need to start by competently managing their present difficult climate situation. The region, which stretches from Mauritania and Mali in the west to Sudan and Eritrea in the east, is home to more than 100 million people, many of them are among the poorest in the world. A lack of weather stations across Africa means that forecasts by national meteorological agencies tend to be too broad to be of much use at a local level. "What we need now are more reliable predictions. So that people can know how much rain will fall in the next one or two weeks and get prepared for it" Emmanuel Oladipo said, adding that "Unfortunately people are not able to do that, due to a lack of communication, limited education  and the inability of weather predicting systems."