Ban Ki-moon, the Secretary-General of the United Nations, has appointed the former Italian Prime Minister Romano Prodi as special envoy to the Sahel region, which covers parts of Senegal, Mauritania, Mali, Algeria, Niger, Chad, Sudan, South Sudan and Eritrea.
To call attention to the developing crisis in the Sahel we're asking our readers to road-test a new social-network platform called Thunderclap, which allows people to send one uniform message, either by tweet or via a post to other social networks, like Facebook.
It's easy to tell Rabiou Mahamadou is a farmer. Like many people in Niger, it's how he's fed his family for his whole life. In the past, he would have used only techniques handed down from generation to generation. But today, things are different.