Which of the following defines turbulence?

Turbulence is best defined as irregular movements caused by air currents. This phenomenon occurs when the smooth flow of air is disrupted, leading to sudden changes in altitude or direction experienced by an aircraft. These disturbances can arise from various sources, such as geographical features like mountains, weather systems, or changes in temperature and pressure. Understanding turbulence is crucial for flight attendants and pilots as it directly affects passenger comfort and safety during a flight.

In contrast, the first option refers to a calm flying experience rather than the erratic movements associated with turbulence. The second option highlights stable weather patterns, which contribute to smooth flight rather than turbulent conditions. The fourth option addresses wind patterns that assist with navigation, which can be beneficial but do not relate to the definition of turbulence.