How does increased altitude typically affect air density?

Increased altitude typically results in a decrease in air density. As one ascends into the atmosphere, the air pressure lowers because the weight of the air above decreases. This reduction in pressure leads to fewer air molecules being present in a given volume, which means that the density of the air diminishes with altitude.

At sea level, air is denser because there is a greater concentration of air molecules due to the higher pressure created by the atmosphere overhead. As altitude increases, the gravitational pull on air molecules weakens slightly, contributing to the lower pressure and, consequently, the lower density of the air. Thus, as aircraft and other objects ascend, they encounter a thinner atmosphere with less resistance and lower lift capabilities due to reduced air density.

Understanding this relationship is crucial in aviation and meteorology, as it has implications for flight performance, engine efficiency, and weather patterns.