By: Katey Markiewicz
What is Wind?
Wind is a sideways movement of air. The air always moves from an area of high pressure to an with low pressure.
What Causes Wind?
Wind is caused by differences in air pressure which is caused by differences in how places are heated by the sun. Cool air has more pressure than warm air.
Local Winds are winds that blow over a short distance. For example, a cool breeze blowing in from the water over a beach is a local wind. Local Winds are created when unequal heating happens near lakes or ocean coasts.
Sea and Land Breezes
A sea breeze is a local wind that blows from an ocean. A sea breeze usually happens during the day unlike land breezes. A land breeze is a local wind that blows from the land over a lake or ocean.
What is a Global Wind and how is it created?
A global wind is a wind that blows over long distances. It also blows in the same direction every time. A global wind is created by unequal heating just like local winds. For example, the sun shines directly over the equator, The sun shines at an angle over the poles. Earth rotates from east to west. Earths rotation makes global winds curve. The way that winds curve is called the Coriolis effect. This makes winds in the Northern Hemisphere curve to the right. It makes winds in the Southern Hemisphere curve to the left.
Horse latitudes are winds that are at 30 degrees north and south latitude. They are also very weak winds. Some people say that hundreds of years ago, sailors sailed in these waters and ran out of food and water for their horses so they eventually had to throw them overboard.
The jet stream is a band of highly strong winds in the upper troposphere. Airplanes use these to travel faster while saving fuel. Jet streams usually blow from west to east at speeds of 200 to 400 kilometers per hour. As jet streams travel around Earth, they wander north and south along a wavy path.
Trade winds lie in between 0 degrees and 30 degrees latitude and are very strong. Sailors used to use these to help move their cargo to other counties so they could trade. When the cold air over the horse latitude sinks, it produces a region of high pressure.
Prevailing Westerlies lie between 30 and 60 degrees north and south latitude. They also blow from the west.