Figure 10.

Mean monthly rainfall and number of hours with visibility reduced to less than 5 km (filled bars) and less than 10 km (empty bars) at Gao during three periods: 1957–1961, 1970–1974, and 1983–1987. The number of hours per month of reduced visibility is on the left-hand vertical axis. The monthly rainfall is shown at the top of each diagram, with the amount in mm indicated on the right-hand vertical axis. [Reproduced with permission from ref. 32 (Copyright 1997, American Meterological Society)].