What Causes Wind? Types, Facts & FAQ
The wind is a common weather element that we experience, and it has a chilling, ominous feel at times. It can arrive unexpectedly out of nowhere, from a still and quiet day to full-blown winds that can cause trees to fall.
What causes wind, and where does it suddenly come from? What dictates its speed and direction? We will explore these answers and touch on how this mighty element is also helpful to our planet. The wind is the horizontal movement of air from one location to another. Let’s have a look!
What Is Wind
Simply put, the wind is air in motion. It is caused by the sun’s uneven heating of the earth’s surface. Because the earth’s surface is made up of different formations, such as water bodies, valleys, plains, vegetation, mountains, cloud, and desert regions, the sun’s radiation is absorbed unevenly.
What Causes Wind To Blow?
Wind exists due to variations in air pressure, which begin with the sun. When sunlight warms the Earth’s surface, it warms the atmosphere too. When it hits the Earth, it does not produce heat evenly; it hits different areas at different angles, resulting in varying degrees of warming.
As the sun’s radiation heats the land unevenly, the air above the surfaces warms and rises as it becomes less dense. Low atmospheric pressure is created as the air rises. As a result, cooler-temperature air sinks, and the sinking continues to raise atmospheric pressure. Convectional currents are formed because of this. Convectional currents form when lighter air masses rise due to higher temperatures and are replaced by cooler, heavier air masses, and the process repeats itself. This air movement is what causes the wind to blow.
The difference in the amount of pressure determines wind speed. The greater the pressure difference, the faster the air rushes to the low pressure. The wind’s direction is determined by the position of the high and low pressures and the Coriolis Force—the invisible force that deflects wind.
What Causes Hurricanes?
Hurricanes originate in tropical regions and are massive storms that develop over the sea. They are formed by a combination of warm water, moist warm air, and light upper-level winds.
Hurricanes begin when masses of warm, moist air rising from the ocean’s surface collide with masses of cooler air. The collision causes the warm water vapor to condense, eventually forming storm clouds and rain. Latent heat is released during condensation, which warms the cool air above and causes it to rise, making way for the warm air coming from below the ocean. As the storm intensifies, warm moist air is drawn in, and much more heat is transferred from the ocean surface to the atmosphere. This continuous heat exchange creates a wind pattern that spins around a relatively calm center: similar to water spinning down a drain. If the conditions remain, the storm will grow more powerful, becoming a hurricane.
Types of Wind
- Local winds: Ordinary winds are local winds. They are influenced by water bodies, vegetation, hills, and mountains. The wind changes direction due to changes in temperature and pressure zones during the night and day. Land and sea breezes and valley and mountain breezes are common examples of local winds.
- Seasonal winds: Seasonal winds blow during a specific season and follow a seasonal pattern. The monsoon is the best example of this. This wind season is felt in southern and eastern Asia. The rapid heating of the land caused by India’s hot summer causes hot air to rise. Moisture-laden winds blow in from the surrounding seas and oceans, bringing torrential rain.
- Polar Westerlies: Winds moving toward the poles appear to curve to the east between 35 and 65 degrees latitude. The winds are known as prevailing westerlies because they are named after the direction from which they originate. Many weather movements in the United States and Canada are caused by dominant westerlies in the Northern Hemisphere.
- Polar Easterlies: Polar easterlies are also known as Polar Hadley cells. They are the cold and dry winds that blow from the high-temperature regions of the polar heights at the south and north poles to the low-pressure areas in the westerlies at high latitudes.
- Gust Front: The leading edge of cool air rushing down and out of a thunderstorm is known as a gust front. When a rainstorm’s downdraft hits the ground, it spreads in all directions. This spreading air can move quickly, creating a gust front as it spreads.
- Windstorm: A windstorm is a storm with mighty winds but no rain.
- Downburst: A downburst is a strong downward current of air caused by a cumulonimbus cloud, usually accompanied by heavy rain or a thunderstorm.
- Doldrums: Doldrums are caused by the sun’s constant radiation. The doldrums are a zone of calm and light winds between the Atlantic and Pacific trade winds. They occur in a low-pressure area around the equator, where the prevailing winds are the calmest.
- Jet stream: Jet streams are winds that can reach hundreds of kilometers per hour at the border of air masses.
How Is Wind Helpful to Earth?
The wind is the world’s fastest-growing electricity source and is one of the most affordable and sustainable forms of renewable energy. Wind power generation produces no harmful by-products and reduces the use of fossil fuels, which are the source of greenhouse gases that cause global warming. The best part is that its supply is limitless.
The wind is the movement of air near Earth’s surface, caused by changes in the temperature of air, land, and water, and gases moving from high-pressure areas to low-pressure areas. Wind can be a gentle breeze one day and a strong gale the next. One of the most powerful winds is a hurricane that develops in tropical regions over the sea caused by warm ocean waters and moist air. Wind can be used as an affordable and renewable energy source to help reduce the impact of climate change.
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