What Are the Layers of the Earth's Atmosphere?

 

What Are the Layers of the Earth's Atmosphere? There are four main layers to the atmosphere: the troposphere, the stratosphere, the mesosphere, and the thermosphere. Each layer has its own unique characteristics. The troposphere is the innermost layer of the atmosphere and extends from the Earth's surface up to about 10 kilometers (6 miles). This is where most of the weather takes place. The air in this layer is warm and moist near the Earth's surface, but becomes colder and drier as you move higher up. The stratosphere is the second layer of the atmosphere and extends from about 10 kilometers (6 miles) to 50 kilometers (31 miles) above the Earth's surface. This layer is characterized by a gradual increase in temperature with height. The stratosphere contains the ozone layer, which helps protect us from the Sun's harmful ultraviolet radiation. The mesosphere is the third layer of the atmosphere and extends from about 50 kilometers (31 miles) to 80 kilometers (50 miles) above the Earth's surface. This layer is characterized by a decrease in temperature with height. The thermosphere is the outermost layer of the atmosphere and extends from about 80 kilometers (50 miles) to 640 kilometers (400 miles) above the Earth's surface. This layer is extremely thin and consists mostly of ionized gas particles. The thermosphere is where auroras occur. The atmosphere is not evenly layered. There are variations in the thickness of each layer depending on latitude and time of day. The atmosphere also has a complex structure with many smaller layers within each of the main layers. But, for simplicity, we can think of the atmosphere as having four main layers.