Data types

Data types
Data type	Description
`Ah`, `Av`	Integral attenuation for horizontal (H) and vertical (V) channels
`Azdr`	Integral attenuation of ZDR (dB) format
`CSR`	Doppler channel clutter-to-signal (CSR) ratio of dBT to -dBZ
`dBT`, `dBTh`, `dBTv`, `DBTr`	Total power
`dBZ`	Clutter corrected reflectivity
`dBZt`	Uncorrected reflectivity
`HCLASS`	Hydrometeor classification Estimated hydrometeor type in the precipitation area
`KDP`	Specific differential phase An indicator of the rate of change of the phase difference between horizontally and vertically polarized pulses of the radar. A greater horizontal shift results in a positive KDP value, and a greater vertical shift results in a negative KDP value. Typical cause for a high KDP area is heavy rain.
`LDRH`, `LDRV`	Linear depolarization ratio H to V (or V to H) The ratio of cross-polar to co-polar reflectivity measured in dB
`LOG`	Log receiver signal-to-noise ratio
`PHIH`, `PHIV`	Horizontal (V) or vertical (V) differential phase Phase difference for the total round trip between radar and the volume where the signal is reflected. `PHIH` is measured between HH and HV channels. `PHIV` is measured between VV and VH channels.
`PHIDP`	Differential phase The phase difference due to propagation between the HH and VV channels of the radar.
`PMI`	Polarimetric meteo index
`R`	Rate of accumulation of precipitation in units of mm/hour For snow, this is usually refers to the liquid equivalent.
`RHOHV`, `RHOH`, `RHOV`	Correlation coefficient between HH and VV (or HH & HV / VV & VH) channels Higher (>0.95) values indicate uniform precipitation areas, and lower values indicate more mixed hydrometeor types, such as melting snow, wet snowflakes, or airborne debris.
`SNR`	Signal-to-noise ratio Generic measurement of signal-noise ratio in dB
`SQI`	Signal quality index A value between 0-1 that measures the signal's Doppler coherency, that is, the correlation between the signal and its Doppler lag: 0 indicates white noise 1 is the perfect Doppler point target
`T`	Total reflectivity Total power returned to the radar in reflectivity units. It typically represents the horizontal reflectivity without ground clutter correction.
`TV`, `TE`	Total vertical (HV enhanced) reflectivity Total reflectivity from the vertical polarization channel (TV) and combination of the horizontal and vertical channel (TE)
`V`	Velocity Average radial velocity (towards or away from the radar) of detected hydrometeor areas
`VC`	Corrected velocity Same as velocity `V`, but corrected for effects of range folding and velocity folding
`V: SHEAR`, `Vc: SHEAR`	Velocity and corrected velocity of wind shear
`W`	Spectral width Variability of Doppler velocity values within the measurement area
`XCOR`	Polar cross-correlation, uncorrected `rhohv` Because this value is not noise corrected, this is a direct indicator of the PHIDP uncertainty.
`Z`	Reflectivity Usually referred to as dBZ, this is the common data type that measures radar signal reflectivity, and is used to estimate precipitation intensity from that. All `Z` measurements are corrected for ground clutter.
`ZV`, `ZE`	Vertical (HV enhanced) reflectivity Total reflectivity from the vertical polarization channel (`ZV`) and combination of the horizontal and vertical channel (`ZE`). Corrected for ground clutter.
`ZC`	Corrected reflectivity Same as reflectivity `Z`, but corrected for attenuation and beam blockage effects
`ZDR`	Differential reflectivity The ratio of SNR in the horizontal channel to the SNR in the vertical channel. Positive values indicate more prominent horizontal echoes and negative values more prominent vertical echoes. Larger hydrometeor sizes are usually identified by high positive ZDR values.
`ZDRC`	Corrected differential reflectivity Same as differential reflectivity `ZDR`, but corrected for attenuation and beam blockage effects

Ah, Av

Integral attenuation for horizontal (H) and vertical (V) channels

Azdr

Integral attenuation of ZDR (dB) format

CSR

Doppler channel clutter-to-signal (CSR) ratio of dBT to -dBZ

dBT, dBTh, dBTv, DBTr

Total power

dBZ

Clutter corrected reflectivity

dBZt

Uncorrected reflectivity

HCLASS

Hydrometeor classification

Estimated hydrometeor type in the precipitation area

KDP

Specific differential phase

An indicator of the rate of change of the phase difference between horizontally and vertically polarized pulses of the radar. A greater horizontal shift results in a positive KDP value, and a greater vertical shift results in a negative KDP value. Typical cause for a high KDP area is heavy rain.

LDRH, LDRV

Linear depolarization ratio H to V (or V to H)

The ratio of cross-polar to co-polar reflectivity measured in dB

LOG

Log receiver signal-to-noise ratio

PHIH, PHIV

Horizontal (V) or vertical (V) differential phase

Phase difference for the total round trip between radar and the volume where the signal is reflected. PHIH is measured between HH and HV channels. PHIV is measured between VV and VH channels.

PHIDP

Differential phase

The phase difference due to propagation between the HH and VV channels of the radar.

PMI

Polarimetric meteo index

R

Rate of accumulation of precipitation in units of mm/hour

For snow, this is usually refers to the liquid equivalent.

RHOHV, RHOH, RHOV

Correlation coefficient between HH and VV (or HH & HV / VV & VH) channels

Higher (>0.95) values indicate uniform precipitation areas, and lower values indicate more mixed hydrometeor types, such as melting snow, wet snowflakes, or airborne debris.

SNR

Signal-to-noise ratio

Generic measurement of signal-noise ratio in dB

SQI

Signal quality index

A value between 0-1 that measures the signal's Doppler coherency, that is, the correlation between the signal and its Doppler lag:

0 indicates white noise
1 is the perfect Doppler point target

T

Total reflectivity

Total power returned to the radar in reflectivity units. It typically represents the horizontal reflectivity without ground clutter correction.

TV, TE

Total vertical (HV enhanced) reflectivity

Total reflectivity from the vertical polarization channel (TV) and combination of the horizontal and vertical channel (TE)

V

Velocity

Average radial velocity (towards or away from the radar) of detected hydrometeor areas

VC

Corrected velocity

Same as velocity V, but corrected for effects of range folding and velocity folding

V: SHEAR, Vc: SHEAR

Velocity and corrected velocity of wind shear

W

Spectral width

Variability of Doppler velocity values within the measurement area

XCOR

Polar cross-correlation, uncorrected rhohv

Because this value is not noise corrected, this is a direct indicator of the PHIDP uncertainty.

Z

Reflectivity

Usually referred to as dBZ, this is the common data type that measures radar signal reflectivity, and is used to estimate precipitation intensity from that.

All Z measurements are corrected for ground clutter.

ZV, ZE

Vertical (HV enhanced) reflectivity

Total reflectivity from the vertical polarization channel (ZV) and combination of the horizontal and vertical channel (ZE). Corrected for ground clutter.

ZC

Corrected reflectivity

Same as reflectivity Z, but corrected for attenuation and beam blockage effects

ZDR

Differential reflectivity

The ratio of SNR in the horizontal channel to the SNR in the vertical channel. Positive values indicate more prominent horizontal echoes and negative values more prominent vertical echoes. Larger hydrometeor sizes are usually identified by high positive ZDR values.

ZDRC

Corrected differential reflectivity

Same as differential reflectivity ZDR, but corrected for attenuation and beam blockage effects