Does temperature increase or decrease with altitude?

Question: Does temperature increase or decrease with altitude?

Does temperature increase or decrease with altitude? This is a common question that many people have, especially when they are planning to travel to high-altitude destinations. The answer is not as simple as it may seem, because temperature changes with altitude in different ways depending on the layer of the atmosphere.

The atmosphere is divided into five main layers: the troposphere, the stratosphere, the mesosphere, the thermosphere and the exosphere. The troposphere is the lowest layer, where we live and where most of the weather occurs. The stratosphere is the second layer, where the ozone layer protects us from harmful ultraviolet radiation. The mesosphere is the third layer, where meteors burn up as they enter the Earth's atmosphere. The thermosphere is the fourth layer, where auroras and satellites occur. The exosphere is the fifth and outermost layer, where the atmosphere gradually fades into space.

In general, temperature decreases with altitude in the troposphere and the mesosphere, but increases with altitude in the stratosphere and the thermosphere. This is because of different factors that affect how heat is transferred and distributed in each layer. In the troposphere, temperature decreases with altitude because air pressure and density decrease as you go higher, which means that air molecules are more spread out and have less kinetic energy. In the stratosphere, temperature increases with altitude because of the absorption of ultraviolet radiation by ozone molecules, which heats up the air. In the mesosphere, temperature decreases with altitude again because air pressure and density continue to decrease and there is less ozone to absorb radiation. In the thermosphere, temperature increases with altitude because of the absorption of extreme ultraviolet and X-ray radiation by atomic oxygen and nitrogen, which ionizes and excites the air molecules.

The rate at which temperature changes with altitude varies depending on the layer and the location. For example, in the troposphere, temperature decreases by about 6.5°C per kilometer on average, but this can vary depending on humidity, latitude and season. In the stratosphere, temperature increases by about 1°C per kilometer on average, but this can vary depending on ozone concentration and solar activity. In the mesosphere, temperature decreases by about 2°C per kilometer on average, but this can vary depending on atmospheric waves and tides. In the thermosphere, temperature can reach thousands of degrees Celsius at high altitudes, but this does not mean that it feels hot, because air density is so low that heat transfer is negligible.

Therefore, to answer the question of whether temperature increases or decreases with altitude, we need to specify which layer of the atmosphere we are talking about and what other factors are involved. There is no simple or universal rule that applies to all situations.