What does 'intermittent' describe when discussing turbulence?

In the context of turbulence, 'intermittent' specifically refers to occurrences that happen 1/3 to 2/3 of the time. This indicates that the turbulence is not present continuously but is experienced regularly enough to be significant.

Describing it this way helps pilots and meteorologists understand the expected frequency and intensity of turbulence during flight. It suggests that while there will be periods of turbulence, there will also be intervals of smoother air. Recognizing the intermittent nature enables better planning and response strategies during flight operations.

The other descriptions provided do not accurately capture the meaning of 'intermittent' in this context. For example, stating turbulence occurs less than 1/3 of the time implies it is rare, while 'consistently throughout' would suggest a steady and uninterrupted experience, which contradicts the notion of intermittency. Additionally, mentioning only certain conditions does not give a clear quantitative measure of frequency. Therefore, the correct understanding aligns with 1/3 to 2/3 of the time, providing an appropriate interval of turbulence for flight preparation.