Which factor most significantly affects the speed of sound in the atmosphere?

The speed of sound in the atmosphere is most significantly affected by ambient temperature. As the temperature increases, the molecules in the air move more rapidly, which facilitates the transmission of sound waves. This increased molecular activity allows sound waves to travel faster through the air.

In warmer conditions, the kinetic energy of air molecules is higher, causing sound waves to propagate more quickly. Conversely, in cooler temperatures, sound travels more slowly because the energy and movement of the air molecules are reduced.

Although humidity, altitude, and wind speed can influence the speed of sound to some extent, these factors do not have as pronounced an effect as temperature. Humidity can slightly increase the speed of sound because moist air is less dense than dry air; however, this effect is significantly smaller. Altitude affects temperature and air density but does not directly determine the speed of sound on its own. Wind speed can alter the effective speed of sound relative to a moving observer or source but does not change the inherent speed of sound in a static medium. Therefore, ambient temperature stands out as the primary factor influencing the speed of sound in the atmosphere.