Shear

Science / Weather / Shear: It is the rate of change over a short duration. In wind shear, it can refer to the frequent change in wind speed within a short distance. It can occur vertically or horizontally. Directional shear is a frequent change in direction within a short distance, which can also occur vertically or horizontally. When used in reference to Doppler radar, it describes the change in radial velocity over short distances horizontally.
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Shear Line

Science / Weather / Shear Line: A line of maximum horizontal wind shear. A narrow zone across which there is an abrupt change in the horizontal wind component parallel to it. MORE

Wind Shear

Science / Weather / Wind Shear: The rate of wind speed or direction change with distance. Vertical wind shear is the rate of change of the wind with respect to altitude. Horizontal wind shear is the rate of change on a horizontal pl MORE

Directional Shear

Science / Weather / Directional Shear: The shear created by a rapid change in wind direction with height. MORE