Which factor will likely increase density altitude?

Density altitude refers to the altitude at which the density of the air is equivalent to a standard atmosphere. It is influenced by temperature, pressure, and humidity. When considering factors that contribute to an increase in density altitude, an increase in ambient temperature is significant.

As the ambient temperature rises, the air becomes less dense, which effectively raises the density altitude. Warmer air causes the molecules in the atmosphere to spread further apart, leading to a decrease in the overall mass of the air at a given altitude. This reduced density makes it more challenging for aircraft to generate lift and can affect engine performance. Therefore, when the ambient temperature increases, the density altitude also increases, resulting in a less favorable condition for aircraft operation.

In contrast, a decrease in ambient temperature would lead to denser air and a lower density altitude. An increase in altitude itself does not directly correlate to the density of the air but rather the pressure, which can also contribute to higher density altitudes if the temperature remains constant. Meanwhile, decreased humidity generally increases air density, as more humid air is less dense than dry air, thus making it an unlikely factor for raising density altitude.