(a) Differentiate between permanent drought and seasonal drought, giving an example of each (b) Highlight any two main causes and two effects of drought (c)...

(a) Permanent drought and seasonal drought

Permanent drought is the condition of continuous, year-round dryness found in desert and semi-desert areas where rainfall is extremely low and unreliable throughout the year; here farming is impossible without irrigation. Example: the Sahara Desert (or the Namib Desert).

Seasonal drought is the regular dry period that occurs every year during the dry season in regions that otherwise have a wet season; the area is watered for part of the year and dry for the rest. Example: the Sudan/Savanna belt of northern Nigeria (or the tropical grasslands generally).

(b) Causes and effects of drought

Two main causes:

• Failure or lateness of the rains caused by shifts in the rain-bearing winds (e.g. the ITD not moving far enough north).
• Human activities such as deforestation and overgrazing that reduce vegetation cover, lower humidity and encourage desertification.

Two effects:

• Crop failure and death of livestock, leading to famine and hunger.
• Drying up of rivers, wells and water sources, causing water shortage and migration of people (environmental refugees).

(c) Methods of minimizing the effects of drought

1. Provide irrigation and construct dams, wells and boreholes to store and supply water.
2. Afforestation and planting of shelter belts, plus growing drought-resistant crops, to check desertification and conserve moisture.