Radar Beam The straight line that a radar pulse travels along. As the radar beam gets further away from the radar, it gets wider and wider.
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The straight line that a radar pulse travels along. As the radar beam gets further away from the radar, it gets wider and wider.
radar beam"The focused electromagnetic emissions from a radar antenna. The beam is defined by the main lobe of the antenna pattern.
radar beam—The focused energy radiated by radar similar to a flashlight or searchlight beam.
radar echo—See echo.
Bending of the radar beam in the vertical which is greater than sub-standard refractive conditions. This causes the beam to be lower than indicated, and often results in extensive ground clutter as well as an overestimation of cloud top heights.
ANOMALOUS PROPAGATION (AP)Non-standard atmospheric temperature or moisture gradients will cause all or part of the radar beam to propagate along a non-normal path.
At far ranges from the radar, a storm may occupy only a portion of the radar beam (which may be several miles across).
In Doppler radar, it is the component of motion that is parallel to the radar beam. RADIATION The process by which energy is propagated through any medium by virue of the wave motion of that medium.
SuperrefractionBending of the radar beam in the vertical which is greater than sub-standard refractive conditions.
The value of Z is a function of the amount of radar beam energy that is back scattered by a target and detected as a signal (or echo). Higher values of Z (and dBZ) thus indicate more energy being back scattered by a target.
This occurs as a result of the radar beam hitting a hail shaft (usually containing hail of greater than 1 inch in diameter). The hail shaft causes the radar beam to be reflected to the ground.
However, other factors can affect reflectivity, such as width of the radar beam, precipitation type, drop size, or the presence of ground clutter or AP.
3 BODY SCATTER - Radar reflectivity phenomina caused when a radar beam strikes a target in the air, and some energy bounces off that object downward, reflects off the ground, then back off the object, and back to the radar, ...
Attenuation: a) Radar definition: It refers to the reduction of the radar beam power due to the reflection or absorption of energy when it strikes a target. The greatest attenuation occurs when the radar beam goes through very heavy rain. b) ...
Beam Width - the angle between the center of the radar beam and the point in the beam where the power of the transmitted energy is one-half of the power at the center's maximum. A WSR-88D radar's beam width is approximately 1 degree.
As "seen" by Doppler radar, it is the component of motion parallel to the radar beam. (The component of motion perpendicular to the beam cannot be seen by the radar.
REFRACTION The bending of light or radar beam as it passes through a zone of contrasting properties, such as atmospheric density, water vapor, or temperature.
Radar that can measure radial velocity, the instantaneous component of motion parallel to the radar beam (i.e., toward or away from the radar antenna).
The first piece of information is the angle of the radar beam with respect to north; called the "azimuth angle".
AP - Anomalous Propagation. Radar term for false (non-precipitation) echoes resulting from nonstandard propagation of the radar beam under certain atmospheric conditions.
Reflectivity: A measure of the fraction of incident radiation falling on a surface that is turned back from it by reflection. Reflectivity also refers to the degree by which precipitation is able to reflect a radar beam.
Radar: "Radio Detection & Ranging" In "Weather" An instrument which transmitts and receives electromagnetic waves for detecting & determining the speed, height, location & type of precipitation.
Radar Beam: A small focused beam of energy radiated ...
plate or in centerfield to measure the velocity of pitched balls, which typically range from 70 to 90 mph. In this position the radar gun cannot measure the speed of a throw from shortstop to first base, since the thrown ball crosses the radar beam ...
If however, the target where flying directly toward (or away from) the radar site, then the measured velocity would be the actual velocity. The velocity component of a target relative to the radar beam is referred to as the "radial velocity".
 See also: Radar, Precipitation, Temperature, Weather, Air
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