What is wind shear characterized by?

Wind shear is defined as a rapid change in wind speed or direction over a short distance in the atmosphere. This phenomenon is crucial for pilots to understand because it can significantly affect aircraft performance during takeoff, landing, and in flight. Wind shear can occur at various altitudes and can be particularly hazardous during the critical phases of flight, such as approach and departure from an airport.

The presence of wind shear can lead to sudden changes in lift and control, making it challenging for pilots to maintain stable flight. This characteristic makes option B the right choice, as it accurately encompasses the essence of wind shear having abrupt shifts rather than gradual changes, consistent patterns, or stagnant air. Each of these other options describes different states of wind behavior but does not capture the essence of the dynamic and potentially dangerous conditions associated with wind shear.