Climate is the average weather condition of a place over a considerable period of time, say 35 years. The two major and relevant elements of climate are rainfall and sunshine, though wind and air mass also constitute elements of climate.
Among these major climatic elements, Nigeria, being in the tropical climatic zone enjoys a favorable amount of these elements especially that of rainfall and sunshine in every part of the country. Rainfall and sunshine help to mark out the two distinct seasons of the year i.e. dry and rainy seasons.
Rainfall and sunshine are fairly distributed, though at one time or the other of the year; these two elements increase and decrease from the South to the North.
It is also worthy to note that wind contributes to the determination of the seasons of the year. When the South-West winds blow across the Atlantic Ocean into Nigeria, it brings about rainfall between April and October and when the North-East winds blow across the Sahara Desert, it brings about dryness and harmattan between November and March. The regular supply of these two (rainfall and sunshine) encourages crop cultivation.
Vegetation on the other hand is the living mantle of plants, which covers much of the land surface forming an important aspect of the physical environment.
The type of vegetation seen in a particular place is dependent on the amount of rainfall available in that area.
For instance, the north, where we have a short supply of rainfall, the vegetation is made up of scattered thorny dwarf trees whereas, in the south where rainfall is heavy, the vegetation is made up of thick evergreen forest.
The main vegetation belts in Nigeria from North to South are:
- Sahel Savanna
- Sudan Savanna
- Guinea Savanna
- Mangrove Swamp
- Rain Forest
Note that Agriculture is best practiced in the open areas of the rain forest and the grassland of the savanna region.