What is a reflectivity factor?

Reflectivity is defined as simply “a measure of the of the fraction of radiation reflected by a given surface; expressed as a ratio of the radiant energy reflected to the total amount of energy incident upon that surface”.

What does radar reflectivity mean?

The Local Radar base reflectivity product is a display of echo intensity (reflectivity) measured in dBZ (decibels). “Reflectivity” is the amount of transmitted power returned to the radar receiver after hitting precipitation, compared to a reference power density at a distance of 1 meter from the radar antenna.

What does radar reflectivity depend on?

In general, a measure of the efficiency of a radar target in intercepting and returning radio energy. It depends upon the size, shape, aspect, and dielectric properties of the target.

What does base reflectivity mean?

Base Reflectivity basically corresponds to the amount of radiation that is scattered or reflected back to the radar by whatever targets are located in the radar beam at a given location.

What factor that determines the maximum measurable range of the radar?

The longer the pulse length, the greater is the range capability of the radar because of the greater amount of energy transmitted. The pulse repetition rate (PRR) determines the maximum measurable range of the radar.

How does reflectivity help meteorologists figure out the weather shown on radar maps?

Reflectivity data shows us the strength of the energy that is returned to the radar after it bounces off precipitation targets. Other non-precipitation targets will return energy, but for now, we will only deal with the precipitation. In general, the stronger the returned energy, the heavier the precipitation.

What is the main factor that creates wind?

Wind is the movement of air, caused by the uneven heating of the Earth by the sun and the Earth’s own rotation. Winds range from light breezes to natural hazards such as hurricanes and tornadoes.

What factors affect radar performance?

The performance of a radar system can be judged by the following: (1) the maximum range at which it can see a target of a specified size, (2) the accuracy of its measurement of target location in range and angle, (3) its ability to distinguish one target from another, (4) its ability to detect the desired target echo …

What is reflectivity in weather radar?

The power being returned to the radar from a target has been previously referred to as reflectivity. It is a measure of the efficiency of a target in intercepting and returning radio frequency energy. Thus, a weather radar system provides a value of “efficiency” with which targets in the atmosphere return the energy transmitted by the radar.

What is the formula for radar reflectivity?

The radar reflectivity can be related to the radar reflectivity factor through the dielectric constant term |K|^2, and the radar wavelength. z = the sum (over i) of (N_i * D_i^6), where N_i is the number of drops of diameter D_i in a pulse resolution volume.

What does Z mean in radar reflectivity factor?

Note that z may be expressed in linear or logarithmic units. The radar reflectivity factor is simply a more meteorologically meaningful way of expressing the radar reflectivity. You can either type in the word you are looking for in the box below or browse by letter.

What is the equivalent reflectivity factor of water?

The equivalent reflectivity factorZemay be estimated from measurements of the radar reflectivity η of precipitation and is defined by where λ is the radar wavelengthand 0.93 is the dielectric factorfor water.