pyart.retrieve.create_cfad#

pyart.retrieve.create_cfad(radar, field_bins, altitude_bins, field='reflectivity', field_mask=None, min_frac_thres=0.1)[source]#

This function returns a Contoured Frequency by Altitude Diagram (CFAD; Yuter et al. 1995), a 2-dimensional histogram that is normalized by the number of points at each altitude. Altitude bins are masked where the counts are less than a minimum fraction of the largest number of counts for any altitude row.

Author: Laura Tomkins (lauramtomkins@gmail.com)

Parameters:

  • radar (Radar) – Radar object used. Can be Radar or Grid object.

  • field_bins (list) – List of bin edges for field values to use for CFAD creation.

  • altitude_bins (list) – List of bin edges for height values to use for CFAD creation.

  • field (str) – Field name to use to look up reflectivity data. In the radar object. Default field name is ‘reflectivity’.

  • field_mask (array) – An array the same size as the field array used to mask values.

  • min_frac_thres (float, optional) – Fraction of values to remove in CFAD normalization (default 0.1). If an altitude row has a total count that is less than min_frac_thres of the largest number of total counts for any altitude row, the bins in that altitude row are masked.

Returns:

  • freq_norm (array) – Array of normalized frequency.

  • height_edges (array) – Array of bin edges for height data.

  • field_edges (array of x coordinates) – Array of bin edges for field data.

References

Yuter, S. E., and R. A. Houze, 1995: Three-Dimensional Kinematic and Microphysical Evolution of Florida Cumulonimbus. Part II: Frequency Distributions of Vertical Velocity, Reflectivity, and Differential Reflectivity. Mon. Wea. Rev. 123, 1941-1963. https://doi.org/10.1175/1520-0493(1995)123%3C1941:TDKAME%3E2.0.CO;2