S-Pol Measurements and products

S-Pol data are provided in CfRadial format (NetCDF). In addition to the standard radar moments, such as reflectivity, radial velocity, and spectrum width, S-Pol also provides the dual-pol variables differential reflectivity, differential phase, specific differential phase, and the cross correlation ratio. Several derived products, such as hydrometeor particle type, precipitation rate, and convectivity and convective/stratiform echo type, are also available. Low-level humidity can be calculated using changes in refractive index between fixed ground targets. The data undergoes a rigorous quality control process. Time series In-phase and Quadrature (I and Q) data can be made available. The following table lists the data variables most commonly provided.

Variable

Dimension Unit  
time time s Seconds since volume start
range range m Range from instrument to center of gate
azimuth time deg Ray azimuth angle
elevation time deg Ray elevation angle
Radar observations
DBZ n_points dBZ Reflectivity
VEL n_points m/s Doppler velocity
WIDTH n_points m/s Spectrum width
ZDR n_points dB Differential reflectivity
PHIDP n_points deg Differential phase
KDP n_points deg/km Specific differential phase
RHOHV n_points   Cross correlation ratio
Derived products
RATE n_points mm/h Precipitation rate
PID n_points   Hydrometeor particle ID

Data example from the PRECIP field campaign

S-Pol data example.