Movement of Air – Overview, Causes, Factors, Examples
The multilayered gaseous envelope surrounding the planet earth is known as the Atmosphere. Earth’s atmosphere is composed of about 78% Nitrogen, 21% oxygen, and 1% other gases. Moreover, the atmosphere is the layer of gases or the layers of gases that covers the planet. It is divided into five different layers or zones: troposphere, stratosphere, mesosphere, thermosphere, and exosphere. The troposphere is the lowest region of the atmosphere that contains Air. It lengthens from the surface of the earth up to 8 to 20 km. Several essential climatic events like cloud formation, lightning; thundering, thunderstorm formation, etc., all take place in the troposphere.
Air is a combination of gases such as nitrogen, oxygen, and carbon dioxide. It also contains water vapor and dust particles suspended in the atmosphere.
Movement of Air: Wind
The movement of air is called wind. It is caused by uneven heating of the earth by the sun and the rotation of the earth. Wind ranges from light breezes to natural hazards such as hurricanes and tornadoes. The main reason for air movement is the differences caused by temperature and pressure. Air which is in warm temperature rises in an upward direction, while the air which is in cold temperature moves downward and is denser and replaces the warm air. This phenomenon is known as air. The wind is the horizontal movement of air. It can be described with direction and speed.
Causes of winds
The given below are some causes of winds:
- The general effect of unequal insolation.
- Effect of the extra-tropical belt of high pressure.
- Unequal heating of land and water.
- Atmospheric disturbances.
Air movement in coastal areas
During the day, in littoral areas, there is a regular inflow of cool air from the sea towards the land. At night, there is a rear inflow of air from land to sea. This happens because, during the daytime, the land gets heated faster than water. Re-radiation of heat from land heats the air above it. The hot air rises and creates an area of low pressure. Seawater does not get heated quickly, so the air above the sea is fairly cool. A high-pressure area forms above seawater as compared to air over land. Thus, cooler air over the sea flows toward the land, where a low-pressure area exists. The movement of air from one region to the other creates winds.
During the night, the reverse flow of air occurs. Lands cool down rapidly. The air above the land becomes cooler. The seawater cools down slowly. The air above the sea is hotter and has a lower air pressure as compared to air pressure above the land. Thus, cooler air present over land flows towards the sea.
Factors Influencing Movements of Air
Depending upon the energy levels and air pressure, various types of atmospheric phenomena occur, such as breeze, wind storms, thunderstorms, monsoon rains, cyclones, etc. varied factors controlling these phenomena are:
- Rotation of earth.
- Presence of high mountain ranges in the path of winds.
- Differences in heating and cooling of land and water bodies.
- Uneven heating of land at different parts of the earth.
- Vaporization and condensation of water vapors.
- The difference in topography over which the wind passes.
Question 1: Define the term wind.
The wind is simply aired in motion, usually in the horizontal direction. Wind ranges from light breezes to natural hazards.
Question 2: What causes the movement of air?
The wind is the movement of air, which is caused by the uneven heating of the earth by the sun and the earth’s own rotation.
Question 3: What are the causes of winds?
Unequal heating of land and water, atmospheric disturbances, and the general effect of unequal insolation are the causes of winds.
Question 4: Write the composition of air in the atmosphere.
It consists of 78%nitrogen, 21%oxygen, and 1% other gases and water vapor.
Question 5: What is the atmosphere?
The multilayered gaseous envelope surrounding the planet earth is known as the atmosphere.
Question 6: Which layer of the atmosphere contains air?
The troposphere is the lowest region of the atmosphere that contains air.
Please Login to comment...