Aid agencies say the combined effects of poor weather conditions and governance have placed millions of lives at risk.
The UN refugee agency says that a record 800,000 people were forced to flee across borders last year. Many of them were displaced by conflicts in their home countries.
In Mali, 320,000 people have been forced from their homes since January because of fighting between government forces and Tuareg rebels.
Many are seeking refuge in neighbouring countries. It is estimated that 65,000 Malian refugees now stay in neighbouring Burkina Faso.
The situation is particularly precarious as the Sahel region is going through a major drought, making it hard for the receiving countries to cope with the influx.
Al Jazeera’s Laura Kyle reports from Burkina Faso’s Djibo and May Welsh reports from Mali’s Timbuktu.