pyart.retrieve.kdp_vulpiani#

pyart.retrieve.kdp_vulpiani(radar, gatefilter=None, fill_value=None, psidp_field=None, kdp_field=None, phidp_field=None, band='C', windsize=10, n_iter=10, interp=False, prefilter_psidp=False, filter_opt=None, parallel=False)[source]#

Estimates Kdp with the Vulpiani method for a 2D array of psidp measurements with the first dimension being the distance from radar and the second dimension being the angles (azimuths for PPI, elev for RHI).The input psidp is assumed to be pre-filtered (for ex. with the filter_psidp function)

Parameters:

  • radar (Radar) – Radar containing differential phase field.

  • gatefilter (GateFilter, optional) – A GateFilter indicating radar gates that should be excluded when analysing differential phase measurements.

  • fill_value (float, optional) – Value indicating missing or bad data in differential phase field, if not specified, the default in the Py-ART configuration file will be used

  • psidp_field (str, optional) – Total differential phase field. If None, the default field name must be specified in the Py-ART configuration file.

  • kdp_field (str, optional) – Specific differential phase field. If None, the default field name must be specified in the Py-ART configuration file.

  • phidp_field (str, optional) – Propagation differential phase field. If None, the default field name must be specified in the Py-ART configuration file.

  • band (char, optional) – Radar frequency band string. Accepted “X”, “C”, “S” (capital or not). It is used to set default boundaries for expected values of Kdp.

  • windsize (int, optional) – Size in # of gates of the range derivative window. Should be even.

  • n_iter (int, optional) – Number of iterations of the method. Default is 10.

  • interp (bool, optional) – If True, all the nans are interpolated.The advantage is that less data are lost (the iterations in fact are “eating the edges”) but some non-linear errors may be introduced.

  • prefilter_psidp (bool, optional) – If set, the psidp measurements will first be filtered with the filter_psidp method, which can improve the quality of the final Kdp.

  • filter_opt (dict, optional) – The arguments for the prefilter_psidp method, if empty, the defaults arguments of this method will be used.

  • parallel (bool, optional) – Flag to enable parallel computation (one core for every psidp profile).

Returns:

  • kdp_dict (dict) – Retrieved specific differential phase data and metadata.

  • phidpr_dict, (dict) – Retrieved differential phase data and metadata.

References

Gianfranco Vulpiani, Mario Montopoli, Luca Delli Passeri, Antonio G. Gioia, Pietro Giordano, and Frank S. Marzano, 2012: On the Use of Dual-Polarized C-Band Radar for Operational Rainfall Retrieval in Mountainous Areas. J. Appl. Meteor. Climatol., 51, 405-425, doi: 10.1175/JAMC-D-10-05024.1.