What are they? By:Ellie Maldonado

What are winds? What causes them?

Imagine you are outside on a cold winter day. You are in a heavy jacket, and suddenly, a big gust of moving air hits you in the face. Now you are more cold than when you came out. This big gust of horizontally moving air is called wind. Wind is caused by uneven heating of Earth's surface. It also happens when one area of land has less pressure than another part, and the air moves in to even it out.

Local Winds

Local Winds are winds that blow over a small area of land. These happen because of unequal heating of land. An example of a local wind is a breeze on the beach. This breeze is a sea breeze. This is caused by unequal heating of the ground underwater and the land. During the daytime, when the warm air on the land rises, the cool air of the water swoops right in and takes its place. This happens by convection. A local wind called a land breeze does just the opposite. During the nighttime, the ocean cools down, and all the warm air rises, leaving the cool air of the land to breeze in and take the place of the warm air. You might be wondering-why is it called a land breeze if it cools down the sea? Well, each wind is named after the place or direction it comes from. This is why a breeze that comes from the land is called a land breeze, and a breeze that comes from the sea is a sea breeze.

Global Winds

A lot of the world's wind travels in convection currents, but some of it travels as global wind. Global winds are another type of wind that blow over larger areas of land, like the globe (hence the name global wind). These are also created by uneven heating of Earth's surface. The Coriolis Effect causes the wind on Earth to curve due to the Earth's tilt, otherwise the wind would go straight. One kind of global wind is the horse latitudes. It is said that hundreds of years ago, sailors going out for trade were stuck in these calm waters, so they let go of there horses to make themselves lighter so the gentle winds could carry them. And so forth they became the horse latitudes. These are areas at the 30 degree north and south latitudes where warm air falls. Next, I'll tell you about jet streams. These winds are found all around the Earth in long, wavy paths. These paths of air 10 km above the Earth's surface are what jets and planes follow. It travels at a speed of 200-400 miles per hour. Now onto trade winds. These were used to get men across the sea for trades with other countries. These winds are located between 0-30 degrees north and south latitude. They all blow from the west. Lastly, we have polar easterlies. These global winds blow air away from the poles. These blow to the west due to the Coriolis Effect. Now you know a little more on wind! Ta-da!