Csu radartools tutorial - Revision history

Bdolan: /* Overview */

2021-08-26T16:31:51Z

Overview

2021-08-25T20:37:20Z

Grid data with Radx2Grid

2021-08-25T20:36:13Z

Unfolding Radial Velocity

2021-08-25T20:27:57Z

Unfolding Radial Velocity

2021-08-25T20:26:28Z

Unfolding Radial Velocity

2021-08-25T20:25:58Z

Unfolding Radial Velocity

2021-08-25T19:44:08Z

Attenuation Correction

2021-08-25T19:37:40Z

Attenuation Correction

2021-08-18T23:32:27Z

Attenuation Correction

2021-08-18T23:28:42Z

Attenuation Correction

@@ Line 8: / Line 8: @@
 * Calculate the attenuation and differential attenuation
 * Despeckle and remove 2nd trip
 = '''Modules available from GitHub'''=

@@ Line 269: / Line 269: @@
      params_file = Radx2Grid.seapol.piston.cart
      outpath = f'{mydir}/grid'
-     radgrid_command = f'Radx2Grid -params {params_file} -f cfqcfile -outdir outpath
+     radgrid_command = f'Radx2Grid -params {params_file} -f {cfqcfile} -outdir {outpath}'

← Older revision		Revision as of 20:36, 25 August 2021
Line 259:		Line 259:
	\|}		\|}
	We can see that there are some errors in this correction method. Sometimes this method works better with unfiltered data, and I could probably play with the parameters a bit to clean it up, but the phase-based method worked pretty good so we will go with that.		We can see that there are some errors in this correction method. Sometimes this method works better with unfiltered data, and I could probably play with the parameters a bit to clean it up, but the phase-based method worked pretty good so we will go with that.
		+
		+
		+	==Grid data with Radx2Grid==
		+	Once we are happy with the changes we've made, we can write out a file with pyart.
		+	cfqcfile = f'{mydir}SEA20190917_071005_qced.cfrad.nc'
		+	pyart.io.write_cfradial(cfqcfile,radar)
		+
		+	And we can setup the things for calling Radx2Grid from the command line.
		+	params_file = Radx2Grid.seapol.piston.cart
		+	outpath = f'{mydir}/grid'
		+	radgrid_command = f'Radx2Grid -params {params_file} -f cfqcfile -outdir outpath

← Older revision		Revision as of 20:27, 25 August 2021
Line 258:		Line 258:

	\|}		\|}
		+	We can see that there are some errors in this correction method. Sometimes this method works better with unfiltered data, and I could probably play with the parameters a bit to clean it up, but the phase-based method worked pretty good so we will go with that.

@@ Line 254: / Line 254: @@
 |-
 |[[File:SEAPOL_example_VEL.png|600px]]
-|[[File:SEAPOL_example_unwrapCV.pn|600px]]
+|[[File:SEAPOL_example_unwrapCV.png|600px]]
-|[[File:SEAPOL_example_regionCV.pn|600px]]
+|[[File:SEAPOL_example_regionCV.png|600px]]
 |}

@@ Line 236: / Line 236: @@
 ==Unfolding Radial Velocity==
-This is an example of using the phase unwrap version. There are two other methods available in Pyart, including:
+In PyART, there are several ways to automatically unfold the radial velocity field around the Nyquist. They all have strengths and weaknesses, and I usually try them all to see what works best on a given dataset. It happens that for this one, a simple unwrapping dealias works pretty well.<br/>
 *pyart.correct.dealias_fourdd
 *pyart.dealias_region_based
-    corrected_velocity = pyart.correct.dealias_unwrap_phase(radar, vel_field=vel_name, corr_vel_field='CV')
+*pyart.correct.dealias_unwrap_phase

@@ Line 209: / Line 209: @@
                bad=np.nan, force_default=False, phase_diff_calc=True,
                min_pts=150)
 ;And to add in the differential reflectivity correction, we can specify diff_atten = True to use the correct coefficients.
@@ Line 221: / Line 227: @@
                min_pts=150,diff_atten = True)
+{|class="wikitable"
-[[File:SEAPOL_example_ZDR.png|600px]]
+!Original
+!Corrected
-[[File:SEAPOL_example_attenDR.png|600px]]
+|-
 ==Unfolding Radial Velocity==

← Older revision		Revision as of 19:37, 25 August 2021
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	[[File:SEAPOL_example_attenDZ.png\|600px]]		[[File:SEAPOL_example_attenDZ.png\|600px]]
		+
		+	;And to add in the differential reflectivity correction, we can specify diff_atten = True to use the correct coefficients.
		+
		+	zdrcorr, sadptt, zdpa = csu_atten_corr.calc_atten(radar.fields['ZDR']['data'],
		+	radar.fields['DP']['data'],
		+	kd=radar.fields['KDP']['data'],
		+	height=gate_heights, a_default=-0.15, deva=0.10,
		+	bad=np.nan, force_default=False, phase_diff_calc=True,
		+	min_pts=150,diff_atten = True)
		+
		+
		+	[[File:SEAPOL_example_ZDR.png\|600px]]
		+
		+	[[File:SEAPOL_example_attenDR.png\|600px]]

	==Unfolding Radial Velocity==		==Unfolding Radial Velocity==

← Older revision		Revision as of 23:32, 18 August 2021
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	min_pts=150)		min_pts=150)

		+	[[File:SEAPOL_example_attenDZ.png\|600px]]

	==Unfolding Radial Velocity==		==Unfolding Radial Velocity==

← Older revision		Revision as of 23:28, 18 August 2021
Line 209:		Line 209:
	bad=np.nan, force_default=False, phase_diff_calc=True,		bad=np.nan, force_default=False, phase_diff_calc=True,
	min_pts=150)		min_pts=150)
		+
		+
		+	==Unfolding Radial Velocity==
		+	This is an example of using the phase unwrap version. There are two other methods available in Pyart, including:
		+	*pyart.correct.dealias_fourdd
		+	*pyart.dealias_region_based
		+	corrected_velocity = pyart.correct.dealias_unwrap_phase(radar, vel_field=vel_name, corr_vel_field='CV')