What happens to air temperature when the altitude decreases?
I'm not sure I understand the question. If a plane is flying overhead at 10,000 feet the outside temperature will be lower than when it lands on the surface of the earth.
When the altitude decreases, or in other words, as you move closer to the Earth's surface, the air temperature tends to increase. This phenomenon is known as the lapse rate.
To understand why this happens, we need to consider how the atmosphere is structured. The Earth's atmosphere is divided into several layers, with the lowest layer being the troposphere, which is where weather occurs. In the troposphere, the temperature generally decreases with increasing altitude at a rate of about 6.5 degrees Celsius per kilometer.
This decrease in temperature is primarily due to two factors: the adiabatic cooling effect and the greenhouse effect. Adiabatic cooling refers to the cooling of air as it expands while rising in the atmosphere. As air moves higher in the troposphere, the decrease in atmospheric pressure causes it to expand, leading to temperature drop.
However, when you move closer to the Earth's surface, you are moving into denser air, which is under higher pressure. This compression of air as you descend leads to the opposite effect: the air molecules become more closely packed together, causing the air temperature to increase. This increase in temperature with decreasing altitude is known as the environmental lapse rate.
It is worth noting that this general trend can be influenced by various other factors, such as sunlight, humidity, and topography. For example, in certain locations, such as mountainous areas or coastal regions where air is influenced by oceanic currents, the temperature patterns may deviate from the typical lapse rate. Therefore, it is important to consider the specific context when studying temperature changes with altitude.