ENH: Improved convective stratiform functions

pyart/correct/attenuation.py

@@ -37,7 +37,7 @@ def calculate_attenuation_zphi(radar, doc=None, fzl=None, smooth_window_len=5,
     ----------
     radar : Radar
         Radar object to use for attenuation calculations. Must have
-        phidp and refl fields.
+        phidp and ref fields.
     doc : float, optional
         Number of gates at the end of each ray to to remove from the
         calculation.
@@ -243,7 +243,7 @@ def calculate_attenuation_zphi(radar, doc=None, fzl=None, smooth_window_len=5,
 
         if end_gate_arr[ray] > smooth_window_len:
             # extract the ray's phase shift,
-            # init. refl. correction and mask
+            # init. ref. correction and mask
             ray_phase_shift = corr_phidp[ray, 0:end_gate_arr[ray]]
             ray_mask = mask[ray, 0:end_gate_arr[ray]]
             ray_refl_linear = refl_linear[ray, 0:end_gate_arr[ray]]
@@ -335,7 +335,7 @@ def calculate_attenuation_philinear(
     ----------
     radar : Radar
         Radar object to use for attenuation calculations. Must have
-        phidp and refl fields.
+        phidp and ref fields.
     doc : float, optional
         Number of gates at the end of each ray to to remove from the
         calculation.
@@ -922,7 +922,7 @@ def calculate_attenuation(radar, z_offset, debug=False, doc=15, fzl=4000.0,
         for i in range(start_ray, end_ray):
             # perform attenuation calculation on a single ray
 
-            # extract the ray's phase shift and init. refl. correction
+            # extract the ray's phase shift and init. ref. correction
             ray_phase_shift = proc_dp_phase_shift[i, 0:end_gate]
             ray_init_refl = init_refl_correct[i, 0:end_gate]
 

pyart/default_config.py

@@ -1024,9 +1024,9 @@
     'HCLASS': radar_echo_classification,        # (55) Hydrometeor class
     'HCLASS2': radar_echo_classification,       # (56) Hydrometeor class
     'ZDRC': corrected_differential_reflectivity,
-                                                # (57) Corrected diff. refl.
+                                                # (57) Corrected diff. ref.
     'ZDRC2': corrected_differential_reflectivity,
-                                                # (58) Corrected diff. refl.
+                                                # (58) Corrected diff. ref.
     'UNKNOWN_59': None,                         # Unknown field
     'UNKNOWN_60': None,                         # Unknown field
     'UNKNOWN_61': None,                         # Unknown field
@@ -1319,11 +1319,11 @@
     'ZDR': corrected_differential_reflectivity,
                         # Differential reflectivity from corrected timeseries
     'UZDR': differential_reflectivity,
-                        # Diff. refl. from uncorrected timeseries
-    'AZDR': None,       # Diff. refl., rainfall atten. corr., corr t.s.
-    'ZDR1': None,       # Diff. refl., corr. t.s., 1st LAG algo.
-    'UZDR1': None,      # Diff. refl., uncorr. t.s., 1st LAG algo.
-    'AZDR1': None,      # Diff. refl., rain. atten. corr., corr. t.s., 1st LAG
+                        # Diff. ref. from uncorrected timeseries
+    'AZDR': None,       # Diff. ref., rainfall atten. corr., corr t.s.
+    'ZDR1': None,       # Diff. ref., corr. t.s., 1st LAG algo.
+    'UZDR1': None,      # Diff. ref., uncorr. t.s., 1st LAG algo.
+    'AZDR1': None,      # Diff. ref., rain. atten. corr., corr. t.s., 1st LAG
 
     'PHI': corrected_differential_phase,
                         # Differential phase from corrected timeseries

pyart/graph/__init__.py

@@ -60,5 +60,6 @@
 from .gridmapdisplay_basemap import GridMapDisplayBasemap
 from .radarmapdisplay import RadarMapDisplay
 from .radarmapdisplay_basemap import RadarMapDisplayBasemap
+from .convstrat_scheme_plot import plot_convstrat_scheme
 
 __all__ = [s for s in dir() if not s.startswith('_')]

pyart/graph/convstrat_scheme_plot.py

@@ -0,0 +1,76 @@
+import numpy as np
+import matplotlib.pyplot as plt
+
+def plot_convstrat_scheme(always_core_thres, use_cosine, max_diff=None, zero_diff_cos_val=None,
+                          use_addition=False, scalar_diff=None):
+    """
+    Plots the scheme used in the convective stratiform classification
+
+    Parameters
+    ----------
+     always_core_thres : float
+        All values above this threshold considered to be convective
+    use_cosine : bool
+        Boolean used to determine if cosine scheme should be used for identifying convective cores (True) or a scalar
+        scheme (False)
+    max_diff : float, optional
+        Maximum difference between background average and reflectivity in order to be classified as convective.
+        "a" value in Eqn. B1 in Yuter and Houze (1997)
+    zero_diff_cos_val : float, optional
+        Value where difference between background average and reflectivity is zero in the cosine function
+        "b" value in Eqn. B1 in Yuter and Houze (1997)
+    use_addition : bool, optional
+        Determines if a multiplier (False) or addition (True) in the scalar difference scheme should be used
+    scalar_diff : float, optional
+        If using a scalar difference scheme, this value is the multiplier or addition to the background average
+
+    """
+
+    # create array of background values
+    bkg_vals = np.linspace(0, 60, 100)
+
+    # create difference array
+    if use_cosine:
+        # cosine scheme
+        diff = max_diff * np.cos(np.pi * bkg_vals / (2 * zero_diff_cos_val))
+    else:
+        if use_addition:
+            # scalar addition scheme
+            diff = (bkg_vals + scalar_diff) - bkg_vals
+        else:
+            # scalar multiplier scheme
+            diff = (bkg_vals * scalar_diff) - bkg_vals
+
+    # if values are less than zero, set to zero
+    diff[diff < 0] = 0
+    # background values greater than always core thres, set to zero
+    diff[bkg_vals > always_core_thres] = 0
+
+    # Now plot
+    fig = plt.figure()
+    ax = plt.gca()
+    # plot difference line
+    ax.plot(bkg_vals, diff, lw=2, color='black')
+    # plot always core thres
+    ax.axvline(x=always_core_thres, lw=1, ls='--', color='red')
+    ax.text(always_core_thres+2, 1, 'Always Core Thres.', color='red')
+    if use_cosine:
+        # plot zero difference cosine value
+        ax.axvline(x=zero_diff_cos_val, lw=1, ls='--', color='green')
+        ax.text(zero_diff_cos_val+2, 0.75, 'Zero Diff. Cosine Val.', color='green')
+        # plot max difference
+        ax.axhline(y=max_diff, lw=1, ls='--', color='blue')
+        ax.text(10, max_diff+0.05, 'Max. Diff.', color='blue')
+    elif use_addition:
+        # plot scalar
+        ax.axhline(y=scalar_diff, lw=1, ls='--', color='orange')
+        ax.text(10, scalar_diff+0.05, 'Scalar Diff.', color='orange')
+    # add grid
+    ax.grid()
+    # set axis limits
+    ax.set_ylim([0, np.max(diff) + 0.2])
+    ax.set_xlim([np.min(bkg_vals), np.max(bkg_vals)])
+    # set axis labels and title
+    ax.set_ylabel('Difference (dBZ - dBZ$_{background}$)')
+    ax.set_xlabel('Background Value (dBZ$_{background}$)')
+    ax.set_title('Convective Stratiform Equation')

pyart/retrieve/__init__.py

@@ -4,7 +4,7 @@
 """
 
 from .kdp_proc import kdp_maesaka, kdp_schneebeli, kdp_vulpiani
-from .echo_class import steiner_conv_strat, hydroclass_semisupervised
+from .echo_class import steiner_conv_strat, conv_strat_yuter, hydroclass_semisupervised
 from .echo_class import get_freq_band
 from .gate_id import map_profile_to_gates, fetch_radar_time_profile
 from .simple_moment_calculations import calculate_snr_from_reflectivity