4. THE ROLE OF TREES IN LAND USE

4.10 Trees and climate

The role trees play in determining climate has been extensively discussed in recent years. In spite of substantial research many important issues remain unresolved. It is necessary to distinguish the role trees can play in affecting the climate at a certain locality, i.e. the microclimate, from the role they can play in determining the climate over larger areas, the macroclimate.

Figure 4.25 Trees have a substantial impact on the microclimate

Trees have a very significant impact on the climate in the locality where they grow. Trees provide shade, and hence lower temperatures. They also help in regulating wind speeds and in retention of moisture in the immediate surroundings. Thus trees can play an important role in determining the microclimate.

With regard to the climate over larger areas, the scientific proof of the role trees can play is not yet very clear. People in most areas in Africa claim that the climate has changed, and in some areas a change towards a drier climate has been verified during this century. To what extent this can be attributed to long-term trends, deforestation or other environmental changes still needs to be determined.