There are many factors which influence the weather and climate in any particular area including:
In simple terms, latitude refers to how far north or south of the equator a place is. Click here to see the major lines of latitude. Latitude is a major factor affecting weather and climate on our planet. The sun’s rays shine most directly on places between the Tropic of Capricorn and the Tropic of Cancer. Because of this, these areas are warm all year round. As we move away from the tropics, the sun’s rays hit the surface more oblique angles. In areas at or near the poles, the sun’s rays rays pass through the atmosphere at a very oblique angle, losing much of their energy. As a result, these areas are cold all year round. Temperate latitudes between the Tropic of Cancer and the Arctic Circle and between the Tropic of Capricorn and the Antarctic Circle have moderate average annual temperatures. However there is great seasonal variation as these areas experience warm summers and cold winters.
Altitude has a marked effect on the temperature of an area. Generally speaking, temperature decreases with height in the lower atmosphere. Therefore, areas at high elevations would tend to experience lower temperatures than nearby areas at much lower elevations. In the lower atmosphere, temperature decreases at a rate of about 6.5 degrees Celsius per kilometer. The rate at which temperature decreases with height is called the environmental lapse rate.
The drop in temperature is due in part to the fact that atmospheric pressure decreases with height. Because of the lower pressure at high elevations, the air is thinner (the molecules of air are farther apart). This makes the air less capable of absorbing or retaining heat. The video below explains in more detail.
In Geography, the term relief may be defined as “the variations in elevation and slope of an area of the Earth’s surface”. When we speak of an area as being flat, gently sloping or mountainous, we are speaking of the relief of that area. When we speak of the elevation (height above sea level) of an area, we are also speaking of relief. The relief of an area can have a significant effect on the climate of that area.
Effect of Relief on Wind
Wind speed is affected by altitude. Near the Earth’s surface, winds are slowed due to friction. At higher elevations wind speeds tend to be considerably higher. The windward slopes of mountains (the side facing the prevailing wind) will generally experience higher wind speeds than nearby lowland areas. Winds speeds are not as high on the leeward side.
Effect of Relief on Rainfall
Relief can influence the amount of precipitation an area receives. When air is forced to rise over a mountain range, it cools and the moisture within it condenses. Clouds form and produce rain. This type of rainfall is called orographic rainfall or relief rainfall. It rains mostly on the windward slopes. As the air moves over the mountain range and starts to descend, it warms. As a result, rainfall is usually low on the leeward side of the mountain range and the area is said to be in a rain shadow. The video below explains the process in greater detail.
Much of the Caribbean region is under the influence of the northeast trade winds. These winds pick up moisture as they blow over the Atlantic. They are forced to rise over the mountains of many Caribbean islands, producing relief rainfall on the windward side. Rain shadows can be found on the leeward side of many Caribbean islands.
Distance from the Sea
Seas and oceans influence the climate of areas near the coast. Seas warm up and cool more slowly than land. Because of this, they help to moderate the temperature of areas near the sea. This means that they have a cooling effect when an area is warm and a warming effect when an area is cold. Therefore, areas near the sea usually have a smaller annual range of temperature than areas at the same latitude that are far from the sea. For instance, in temperate latitudes, areas near the sea tend to have warmer winters and cooler summers than areas far from the sea.
Land and Sea Breezes
Land and sea breezes occur in coastal areas. They occur because the land and the sea heat up and cool down at different rates. Sea breezes occur during the day. During the day, the land heats up faster than the sea. Air over the land heats up and rises, creating an area of lower pressure over the land. Cooler denser air from over the sea flows to the land to replace it.
At night, the land cools faster than the sea. The air over the land cools and sinks, creating higher pressure over the land. This cooler denser air flows from the land to the sea. This is called a land breeze.
A prevailing wind is a surface wind that blows predominantly from one direction. The prevailing wind in an area can impact weather and climate. In the Caribbean the northeast trade wind is the prevailing wind. It blows from the Atlantic bringing moisture and causing relief rainfall as it rises over mountains.
Some places are influenced by more than one prevailing wind. In some parts West Africa, including Ghana, Cote d’Ivoire and Senegal, the northeast trade wind blows from the Sahara between November and the middle of March. This prevailing wind is dry and prevents rainfall. Between June and November, the southeast trade wind becomes the prevailing wind in these areas. It blows from the Atlantic, bringing moisture and causing cloud formation and rainfall.
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