Droughts can grip the vast Sahel region of Africa for decades, dramatically altering the border where forest and savannahs give way to the Sahara Desert. Predicting those droughts is vital, but hard.
Droughts can grip the vast Sahel region of Africa for decades, dramatically altering the border where forest and savannahs give way to the Sahara Desert. Predicting those droughts is vital, but hard.