State with specific examples, how each of the... | WAEC SSCE - Geography - 1999

Question 1 Report

State with specific examples, how each of the following factors affect(s) the climate of adjacent coastlands:

(a) Winds (b) Ocean currents (c) Distance from the sea

Answer

(a) Winds

Winds blowing from the sea onto the land (onshore winds) are moisture-laden; they bring cloud, high humidity and rainfall to coastlands, for example the south-west monsoon giving heavy rain to the Guinea coast.
Winds blowing from the land carry little moisture and produce dry conditions, for example the dusty, dry Harmattan reaching the coast in the dry season.
Warm winds raise coastal temperatures while cold winds lower them, so wind direction and source strongly control the temperature and rainfall of adjacent coastlands.

(b) Ocean currents

Warm currents flowing along a coast raise the temperature of the air above them and of the adjacent land, and add moisture, encouraging rainfall; the warm Guinea Current keeps the West African coast warm and wet.
Cold currents lower coastal temperatures, and because the cool air resists rising they suppress rainfall, producing aridity and coastal fogs; the cold Benguela Current gives the dry Namib coast, and the Canary Current cools north-west Africa's coast.

(c) Distance from the sea

Coastlands lie close to the sea, which heats and cools slowly, so they enjoy a maritime (equable) climate: mild winters, cool summers and a small annual range of temperature (for example Lagos).
The sea is a source of moisture, so coasts generally receive higher and more reliable rainfall and higher humidity.
As one moves inland the moderating influence weakens; places far from the sea have a continental climate with hot summers, cold winters, a large temperature range and lower rainfall (for example Kano compared with Lagos).

Answer Details

(a) Winds

Winds blowing from the sea onto the land (onshore winds) are moisture-laden; they bring cloud, high humidity and rainfall to coastlands, for example the south-west monsoon giving heavy rain to the Guinea coast.
Winds blowing from the land carry little moisture and produce dry conditions, for example the dusty, dry Harmattan reaching the coast in the dry season.
Warm winds raise coastal temperatures while cold winds lower them, so wind direction and source strongly control the temperature and rainfall of adjacent coastlands.

(b) Ocean currents

Warm currents flowing along a coast raise the temperature of the air above them and of the adjacent land, and add moisture, encouraging rainfall; the warm Guinea Current keeps the West African coast warm and wet.
Cold currents lower coastal temperatures, and because the cool air resists rising they suppress rainfall, producing aridity and coastal fogs; the cold Benguela Current gives the dry Namib coast, and the Canary Current cools north-west Africa's coast.

(c) Distance from the sea

Coastlands lie close to the sea, which heats and cools slowly, so they enjoy a maritime (equable) climate: mild winters, cool summers and a small annual range of temperature (for example Lagos).
The sea is a source of moisture, so coasts generally receive higher and more reliable rainfall and higher humidity.
As one moves inland the moderating influence weakens; places far from the sea have a continental climate with hot summers, cold winters, a large temperature range and lower rainfall (for example Kano compared with Lagos).

State with specific examples, how each of the following factors affect(s) the climate of adjacent coastlands: (a) Winds (b) Ocean currents (c) Distance from...