5. state do the land gales blow on the earth's surface?
Answers
The Wind is air in motion.
The Wind is caused by air moving from areas of high pressure to areas of low pressure. It is produced by the uneven heating of the earth’s surface by the Sun. Some parts of the earth are warm and some, cold.Warm air, which weighs less than cold air, rises. Cool air moves in and replaces the rising warm air. This movement of air is what makes the wind blow.
You can feel the wind. Take a walk in the park and enjoy the cool breeze touching your body. Watch the leaves and flowers falling from the trees. Watch little kids playing with balloons and kites.
Flying a kite shows the wind speed and direction. A parachuter takes the help of wind to land safely. A sailor takes the help of the wind to guide him through.
Breeze, gusts, gales, hurricanes, tornadoes, storms, are all types of winds depending upon their intensity and power.
Winds
The moving air is called the wind.
Air expands on heating and contracts on cooling. Warm air, being lighter than cool air, rises up, whereas relatively cooler air, being heavier than the warm air, sinks towards the earth's surface. This is due to convection, a mode of transfer of heat. As warm air rises up, reducing air pressure at that place, cool air moves in to take the place of warm air. Winds are caused by variations in air pressure.
The wind blows from a region of high pressure to a region of low pressure.
The speed of the wind mainly depends on the difference between the pressures of the air in the two regions.
When air moves at high speeds, it creates a low-pressure area.
High speed winds are known to blow away thatched and tiled roofs in rural and semi-urban areas.
Strong winds can uproot trees and electric poles, and even snap cables.
The instrument used to measure the speed of wind is called an anemometer. It is usually fixed on top of a building.
Wind currents
Wind currents occur due to:
Uneven heating between the regions near the equator and the poles and the rotation of the earth.
Uneven heating of land and water in coastal areas.
The equatorial and tropical regions are hotter than the polar regions as they get maximum heat from the sun. The warm air at the equator rises, and the cold air moves in from the polar regions. The air moves due to uneven heating of the earth’s surface between the equator and poles, which results in the circulation of the wind across the globe. But the wind flow is not in the exact north-south direction because a change in direction is caused by the rotation of the earth.
Monsoon winds
The word monsoon is derived from the Arabic word "mausam," which means season. The winds from the ocean carry water in the form of water vapour and cause rain. These are called monsoon winds.