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What Are All of Those Circles You See Out Of Your Airplane Window?
A common sight that seems unnatural
If you’ve ever glanced out the window during a long flight and looked down at the ground below, you might have seen an unusual sight. The ground seems to be filled with tiny green circles. In some places, these circles are ubiquitous, seeming to cover the Earth like some sort of strange pox. In other places, the circles are notable because they appear seemingly in the middle of a desert or arid plain. If you look even closer, you will notice that some of these circles are cut in half, and others are three-quarters full. What the heck are these? To the untrained eye, they look unnatural. And in a way, they are.
What you are seeing is the backbone of modern agriculture. These circles are the result of a system known as center-pivot irrigation. Center-pivot irrigation is a system where a long irrigation arm slowly moves in a circle from a central point and provides much needed water to crops. They create these green circles because only the areas under the irrigation arm receive water and, therefore, become much lusher and healthier than the surrounding land.
A center-pivot irrigation system fuels each one of those circles that looks so tiny from the air. Some of these circles are dozens of acres in diameter with the largest being over 100 acres. When you look out and see hundreds of these circles, you see thousands of acres of active farmland.
These circles can be seen almost everywhere. They are particularly common and dense in the American plains. But they also appear in the deserts of the American Southwest and even in places like Saudi Arabia.
You have likely seen these common pieces of farm equipment on the ground. They look like long metal arms with small rubber tires that sit in the middle of farm fields. You might even know that these apparatuses are used for irrigation. But from ground level, it is hard to see…
