pyrad.proc.process_dda#

pyrad.proc.process_dda(procstatus, dscfg, radar_list=None)[source]#

Estimates horizontal wind speed and direction with a multi-doppler approach This method uses the python package pyDDA

Parameters:

  • procstatus (int) – Processing status: 0 initializing, 1 processing volume, 2 post-processing

  • dscfg (dictionary of dictionaries) –

    data set configuration. Accepted Configuration Keywords:

    datatype : string. Dataset keyword
    The input data type, must contain
    "V" or "Vc", and,
    "dBuZ", "dBZ", or "dBZc"

gridconfig : dictionary. Dataset keyword
    Dictionary containing some or all of this keywords:
    xmin, xmax, ymin, ymax, zmin, zmax : floats
        minimum and maximum horizontal distance from grid origin [km]
        and minimum and maximum vertical distance from grid origin [m]
        Defaults -40, 40, -40, 40, 0., 10000.
    latmin, latmax, lonmin, lonmax : floats
        minimum and maximum latitude and longitude [deg], if specified
        xmin, xmax, ymin, ymax will be ignored
    hres, vres : floats
        horizontal and vertical grid resolution [m]
        Defaults 1000., 500.
    latorig, lonorig, altorig : floats
        latitude and longitude of grid origin [deg] and altitude of
        grid origin [m MSL]
        Defaults the latitude, longitude and altitude of the radar
wfunc : str. Dataset keyword
    the weighting function used to combine the radar gates close to a
    grid point. Possible values BARNES, BARNES2, CRESSMAN, NEAREST
    Default NEAREST
roif_func : str. Dataset keyword
    the function used to compute the region of interest.
    Possible values: dist_beam, constant
roi : float. Dataset keyword
    the (minimum) radius of the region of interest in m. Default half
    the largest resolution
beamwidth : float. Dataset keyword
    the radar antenna beamwidth [deg]. If None that of the key
    radar_beam_width_h in attribute instrument_parameters of the radar
    object will be used. If the key or the attribute are not present
    a default 1 deg value will be used
beam_spacing : float. Dataset keyword
    the beam spacing, i.e. the ray angle resolution [deg]. If None,
    that of the attribute ray_angle_res of the radar object will be
    used. If the attribute is None a default 1 deg value will be used
signs : list of integers
    The sign of the velocity field for every radar object.
    A value of 1 represents when
    positive values velocities are towards the radar, -1 represents
    when negative velocities are towards the radar.
Co : float
    Weight for cost function related to observed radial velocities.
    Default: 1.
Cm : float
    Weight for cost function related to the mass continuity equation.
    Default: 1500.
Cx: float
    Smoothing coefficient for x-direction
Cy: float
    Smoothing coefficient for y-direction
Cz: float
    Smoothing coefficient for z-direction
Cb: float
    Coefficient for sounding constraint
Cv: float
    Weight for cost function related to vertical vorticity equation.
Cmod: float
    Coefficient for model constraint
Cpoint: float
    Coefficient for point constraint
wind_tol: float
    Stop iterations after maximum change in winds is less than this
    value.
frz : float
    The freezing level in meters. This is to tell PyDDA where to use
    ice particle fall speeds in the wind retrieval verus liquid.

  • radar_list (list of Radar objects) – Optional. list of radar objects

Returns:

  • new_dataset (dict) –

    dictionary containing the output fields

    ”wind_vel_h_u”, “wind_vel_h_v” and “wind_vel_v”

  • ind_rad (int) – radar index