Factors Influencing Weather and Climate

Relief and Altitude

Relief refers to the variations in elevations and slope of a particular area on the earth’s surface. For example, when we say an area is flat, gently sloping or mountainous (hilly) we are describing the relief of the land. The relief of an area can influence the weather and climate of that area.  Generally, air temperature decreases with altitude because air at higher altitudes is less dense and cooler. Temperature decreases with height on average 10^oC/km.

Latitude

Latitude is one of the most influential factors of temperature. Latitudes are imaginary lines drawn around the earth parallel to the equator.  Two factors affect the temperature: the angle of the overhead sun and the thickness of the atmosphere. At the equator the over-head sun is high in the sky, as result, high intensity of insolation is received.  On the other hand, at the poles, the sun is low in the sky so less energy or heat is received resulting in cooler temperatures.

Secondly, the thickness of the atmosphere affects temperature. At higher latitudes reduced sunrays strike the earth’s surface. The heat is spread over a larger area and is diffused resulting in lower temperatures in these areas. 

Distance from the Sea

Land heats and cools more quickly than water; this affects the temperatures of coastal and inland areas. Places nearer to the sea will have fewer variations in temperature than places further inland. The sea moderates the temperatures near the coastal areas.  Water takes up heat and emits it much slower than land. This is known as maritime influence. The sea has little influence on the interior of continents. Here the temperatures are more extreme. These areas are under continental influence.

Land and Sea Breeze

Land and sea does not heat up at the same rate. The earth’s surface heats up faster than the ocean as a result; there is a lower pressure over the land than the sea. Wind blows from high pressure to low pressure. Therefore during the day, the wind blows from the sea to the land lowering the temperature. On the other hand, during the night, the land cools and the seas stay warm. The low pressure is now over the sea causing the breeze to blow from the land towards the sea.