What effect does high temperature have on air density?

High temperature decreases air density. This relationship is based on the fundamental principles of thermodynamics and the behavior of gases. When air is heated, its molecules gain kinetic energy, causing them to move more rapidly and spread apart. As a result, the overall volume of air increases while the mass remains constant. This leads to a decrease in density, which is defined as mass per unit volume.

In aviation and meteorology, understanding how temperature affects air density is crucial. Lower air density can lead to reduced aerodynamic efficiency for aircraft, affecting lift and performance. It's also significant for weather patterns, as changes in temperature can impact atmospheric pressure and wind patterns.

In contrast, high air density is usually associated with cooler temperatures, where air molecules are more tightly packed and heavier for a given volume. This phenomena is vital for pilots and engineers who must consider air density in their calculations for performance and safety.