xarray GAMIC backend#

In this example, we read GAMIC (HDF5) data files using the xarray gamic backend.

[1]:

import glob
import wradlib as wrl
import warnings

warnings.filterwarnings("ignore")
import matplotlib.pyplot as pl
import numpy as np
import xarray as xr

try:
    get_ipython().run_line_magic("matplotlib inline")
except:
    pl.ion()

/home/runner/micromamba-root/envs/wradlib-tests/lib/python3.11/site-packages/tqdm/auto.py:22: TqdmWarning: IProgress not found. Please update jupyter and ipywidgets. See https://ipywidgets.readthedocs.io/en/stable/user_install.html
  from .autonotebook import tqdm as notebook_tqdm

Load ODIM_H5 Volume Data#

[2]:

fpath = "hdf5/DWD-Vol-2_99999_20180601054047_00.h5"
f = wrl.util.get_wradlib_data_file(fpath)
vol = wrl.io.open_gamic_dataset(f)

Downloading file 'hdf5/DWD-Vol-2_99999_20180601054047_00.h5' from 'https://github.com/wradlib/wradlib-data/raw/pooch/data/hdf5/DWD-Vol-2_99999_20180601054047_00.h5' to '/home/runner/work/wradlib/wradlib/wradlib-data'.

Inspect RadarVolume#

[3]:

display(vol)

<wradlib.RadarVolume>
Dimension(s): (sweep: 10)
Elevation(s): (28.0, 18.0, 14.0, 11.0, 8.2, 6.0, 4.5, 3.1, 1.7, 0.6)

Inspect root group#

The sweep dimension contains the number of scans in this radar volume. Further the dataset consists of variables (location coordinates, time_coverage) and attributes (Conventions, metadata).

[4]:

vol.root

[4]:

<xarray.Dataset>
Dimensions:              (sweep: 10)
Dimensions without coordinates: sweep
Data variables:
    volume_number        int64 0
    platform_type        <U5 'fixed'
    instrument_type      <U5 'radar'
    primary_axis         <U6 'axis_z'
    time_coverage_start  <U20 '2018-06-01T05:40:47Z'
    time_coverage_end    <U20 '2018-06-01 05:44:17Z'
    latitude             float64 ...
    longitude            float64 ...
    altitude             float64 ...
    sweep_group_name     (sweep) <U7 'sweep_0' 'sweep_1' ... 'sweep_8' 'sweep_9'
    sweep_fixed_angle    (sweep) float64 28.0 18.0 14.0 11.0 ... 4.5 3.1 1.7 0.6
Attributes:
    version:          None
    title:            None
    institution:      None
    references:       None
    source:           None
    history:          None
    comment:          im/exported using wradlib
    instrument_name:  None
    fixed_angle:      28.0

xarray.Dataset

Dimensions:
- sweep: 10
Coordinates: (0)
Data variables: (11)
- volume_number
  ()
  int64
  0
```
array(0)
```
- platform_type
  ()
  <U5
  'fixed'
```
array('fixed', dtype='<U5')
```
- instrument_type
  ()
  <U5
  'radar'
```
array('radar', dtype='<U5')
```
- primary_axis
  ()
  <U6
  'axis_z'
```
array('axis_z', dtype='<U6')
```
- time_coverage_start
  ()
  <U20
  '2018-06-01T05:40:47Z'
```
array('2018-06-01T05:40:47Z', dtype='<U20')
```
- time_coverage_end
  ()
  <U20
  '2018-06-01 05:44:17Z'
```
array('2018-06-01 05:44:17Z', dtype='<U20')
```
- latitude
  ()
  float64
  ...
  long_name :
  latitude
  units :
  degrees_north
  positive :
  up
  standard_name :
  latitude
```
[1 values with dtype=float64]
```
- longitude
  ()
  float64
  ...
  long_name :
  longitude
  units :
  degrees_east
  standard_name :
  longitude
```
[1 values with dtype=float64]
```
- altitude
  ()
  float64
  ...
  long_name :
  altitude
  units :
  meters
  standard_name :
  altitude
```
[1 values with dtype=float64]
```
- sweep_group_name
  (sweep)
  <U7
  'sweep_0' 'sweep_1' ... 'sweep_9'
```
array(['sweep_0', 'sweep_1', 'sweep_2', 'sweep_3', 'sweep_4', 'sweep_5',
       'sweep_6', 'sweep_7', 'sweep_8', 'sweep_9'], dtype='<U7')
```
- sweep_fixed_angle
  (sweep)
  float64
  28.0 18.0 14.0 11.0 ... 3.1 1.7 0.6
```
array([28. , 18. , 14. , 11. ,  8.2,  6. ,  4.5,  3.1,  1.7,  0.6])
```
Indexes: (0)
Attributes: (9)
version :
None
title :
None
institution :
None
references :
None
source :
None
history :
None
comment :
im/exported using wradlib
instrument_name :
None
fixed_angle :
28.0

Inspect sweep group(s)#

The sweep-groups can be accessed via their respective keys. The dimensions consist of range and time with added coordinates azimuth, elevation, range and time. There will be variables like radar moments (DBZH etc.) and sweep-dependend metadata (like fixed_angle, sweep_mode etc.).

[5]:

display(vol[0])

<xarray.Dataset>
Dimensions:            (azimuth: 360, range: 360)
Coordinates:
  * azimuth            (azimuth) float64 0.5 1.5 2.5 3.5 ... 357.5 358.5 359.5
  * range              (range) float32 50.0 150.0 250.0 ... 3.585e+04 3.595e+04
    elevation          (azimuth) float64 ...
    rtime              (azimuth) datetime64[ns] 2018-06-01T05:40:57.362999808...
    sweep_mode         <U20 ...
    longitude          float64 ...
    latitude           float64 ...
    altitude           float64 ...
    time               datetime64[ns] 2018-06-01T05:40:47.076999936
Data variables: (12/16)
    DBZH               (azimuth, range) float32 ...
    DBZV               (azimuth, range) float32 ...
    KDP                (azimuth, range) float32 ...
    RHOHV              (azimuth, range) float32 ...
    DBTH               (azimuth, range) float32 ...
    DBTV               (azimuth, range) float32 ...
    ...                 ...
    WRADV              (azimuth, range) float32 ...
    PHIDP              (azimuth, range) float32 ...
    sweep_number       int64 ...
    prt_mode           <U7 ...
    follow_mode        <U7 ...
    sweep_fixed_angle  float64 28.0
Attributes:
    fixed_angle:  28.0

xarray.Dataset

Dimensions:
- azimuth: 360
- range: 360
Coordinates: (9)
- azimuth
  (azimuth)
  float64
  0.5 1.5 2.5 ... 357.5 358.5 359.5
  standard_name :
  ray_azimuth_angle
  long_name :
  azimuth_angle_from_true_north
  units :
  degrees
  axis :
  radial_azimuth_coordinate
```
array([  0.5,   1.5,   2.5, ..., 357.5, 358.5, 359.5])
```
- range
  (range)
  float32
  50.0 150.0 ... 3.585e+04 3.595e+04
  units :
  meters
  standard_name :
  projection_range_coordinate
  long_name :
  range_to_measurement_volume
  axis :
  radial_range_coordinate
  meters_between_gates :
  100.0
  spacing_is_constant :
  true
  meters_to_center_of_first_gate :
  50.0
```
array([   50.,   150.,   250., ..., 35750., 35850., 35950.], dtype=float32)
```
- elevation
  (azimuth)
  float64
  ...
  standard_name :
  ray_elevation_angle
  long_name :
  elevation_angle_from_horizontal_plane
  units :
  degrees
  axis :
  radial_elevation_coordinate
```
[360 values with dtype=float64]
```
- rtime
  (azimuth)
  datetime64[ns]
  2018-06-01T05:40:57.362999808 .....
  standard_name :
  time
```
array(['2018-06-01T05:40:57.362999808', '2018-06-01T05:40:57.398999808',
       '2018-06-01T05:40:57.435000064', ..., '2018-06-01T05:40:57.256000000',
       '2018-06-01T05:40:57.292000000', '2018-06-01T05:40:57.326999808'],
      dtype='datetime64[ns]')
```
- sweep_mode
  ()
  <U20
  ...
```
[1 values with dtype=<U20]
```
- longitude
  ()
  float64
  ...
  long_name :
  longitude
  units :
  degrees_east
  standard_name :
  longitude
```
[1 values with dtype=float64]
```
- latitude
  ()
  float64
  ...
  long_name :
  latitude
  units :
  degrees_north
  positive :
  up
  standard_name :
  latitude
```
[1 values with dtype=float64]
```
- altitude
  ()
  float64
  ...
  long_name :
  altitude
  units :
  meters
  standard_name :
  altitude
```
[1 values with dtype=float64]
```
- time
  ()
  datetime64[ns]
  2018-06-01T05:40:47.076999936
```
array('2018-06-01T05:40:47.076999936', dtype='datetime64[ns]')
```
Data variables: (16)
- DBZH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Equivalent reflectivity factor H
  standard_name :
  radar_equivalent_reflectivity_factor_h
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- DBZV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Equivalent reflectivity factor V
  standard_name :
  radar_equivalent_reflectivity_factor_v
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- KDP
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  deg/km
  long_name :
  Specific differential phase HV
  standard_name :
  radar_specific_differential_phase_hv
  units :
  degrees per kilometer
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- RHOHV
  (azimuth, range)
  float32
  ...
  format :
  UV16
  is_dft :
  0
  long_name :
  Correlation coefficient HV
  standard_name :
  radar_correlation_coefficient_hv
  units :
  unitless
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- DBTH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Total power H (uncorrected reflectivity)
  standard_name :
  radar_equivalent_reflectivity_factor_h
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- DBTV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Total power V (uncorrected reflectivity)
  standard_name :
  radar_equivalent_reflectivity_factor_v
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- ZDR
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dB
  long_name :
  Log differential reflectivity H/V
  standard_name :
  radar_differential_reflectivity_hv
  units :
  dB
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- VRADH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Radial velocity of scatterers away from instrument H
  standard_name :
  radial_velocity_of_scatterers_away_from_instrument_h
  units :
  meters per seconds
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- VRADV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Radial velocity of scatterers away from instrument V
  standard_name :
  radial_velocity_of_scatterers_away_from_instrument_v
  units :
  meters per second
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- WRADH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Doppler spectrum width H
  standard_name :
  radar_doppler_spectrum_width_h
  units :
  meters per seconds
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- WRADV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Doppler spectrum width V
  standard_name :
  radar_doppler_spectrum_width_v
  units :
  meters per second
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- PHIDP
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  deg
  long_name :
  Differential phase HV
  standard_name :
  radar_differential_phase_hv
  units :
  degrees
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- sweep_number
  ()
  int64
  ...
```
[1 values with dtype=int64]
```
- prt_mode
  ()
  <U7
  ...
```
[1 values with dtype=<U7]
```
- follow_mode
  ()
  <U7
  ...
```
[1 values with dtype=<U7]
```
- sweep_fixed_angle
  ()
  float64
  28.0
```
array(28.)
```

Indexes: (2)

azimuth

PandasIndex

PandasIndex(Float64Index([  0.5,   1.5,   2.5,   3.5,   4.5,   5.5,   6.5,   7.5,   8.5,
                9.5,
              ...
              350.5, 351.5, 352.5, 353.5, 354.5, 355.5, 356.5, 357.5, 358.5,
              359.5],
             dtype='float64', name='azimuth', length=360))

range

PandasIndex

PandasIndex(Float64Index([   50.0,   150.0,   250.0,   350.0,   450.0,   550.0,   650.0,
                750.0,   850.0,   950.0,
              ...
              35050.0, 35150.0, 35250.0, 35350.0, 35450.0, 35550.0, 35650.0,
              35750.0, 35850.0, 35950.0],
             dtype='float64', name='range', length=360))

Attributes: (1)
fixed_angle :
28.0

Goereferencing#

[6]:

swp = vol[0].copy().pipe(wrl.georef.georeference_dataset)

Plotting#

[7]:

swp.DBZH.plot.pcolormesh(x="x", y="y")
pl.gca().set_aspect("equal")

../../_images/notebooks_fileio_wradlib_gamic_backend_14_0.png

[8]:

fig = pl.figure(figsize=(10, 10))
swp.DBZH.wradlib.plot_ppi(proj="cg", fig=fig)

[8]:

<matplotlib.collections.QuadMesh at 0x7f3d3414d910>

../../_images/notebooks_fileio_wradlib_gamic_backend_15_1.png

[9]:

import cartopy
import cartopy.crs as ccrs
import cartopy.feature as cfeature

map_trans = ccrs.AzimuthalEquidistant(
    central_latitude=swp.latitude.values, central_longitude=swp.longitude.values
)

[10]:

map_proj = ccrs.AzimuthalEquidistant(
    central_latitude=swp.latitude.values, central_longitude=swp.longitude.values
)
pm = swp.DBZH.wradlib.plot_ppi(proj=map_proj)
ax = pl.gca()
ax.gridlines(crs=map_proj)
print(ax)

< GeoAxes: +proj=aeqd +ellps=WGS84 +lon_0=6.4569489 +lat_0=50.9287272 +x_0=0.0 +y_0=0.0 +no_defs +type=crs >

../../_images/notebooks_fileio_wradlib_gamic_backend_17_1.png

[11]:

map_proj = ccrs.Mercator(central_longitude=swp.longitude.values)
fig = pl.figure(figsize=(10, 8))
ax = fig.add_subplot(111, projection=map_proj)
pm = swp.DBZH.wradlib.plot_ppi(ax=ax)
ax.gridlines(draw_labels=True)

[11]:

<cartopy.mpl.gridliner.Gridliner at 0x7f3d3da7dc90>

../../_images/notebooks_fileio_wradlib_gamic_backend_18_1.png

[12]:

import cartopy.feature as cfeature


def plot_borders(ax):
    borders = cfeature.NaturalEarthFeature(
        category="physical", name="coastline", scale="10m", facecolor="none"
    )
    ax.add_feature(borders, edgecolor="black", lw=2, zorder=4)


map_proj = ccrs.Mercator(central_longitude=swp.longitude.values)
fig = pl.figure(figsize=(10, 8))
ax = fig.add_subplot(111, projection=map_proj)

DBZH = swp.DBZH
pm = DBZH.where(DBZH > 0).wradlib.plot_ppi(ax=ax)
plot_borders(ax)
ax.gridlines(draw_labels=True)

[12]:

<cartopy.mpl.gridliner.Gridliner at 0x7f3d3d39b950>

../../_images/notebooks_fileio_wradlib_gamic_backend_19_1.png

[13]:

import matplotlib.path as mpath

theta = np.linspace(0, 2 * np.pi, 100)
center, radius = [0.5, 0.5], 0.5
verts = np.vstack([np.sin(theta), np.cos(theta)]).T
circle = mpath.Path(verts * radius + center)

map_proj = ccrs.AzimuthalEquidistant(
    central_latitude=swp.latitude.values,
    central_longitude=swp.longitude.values,
)
fig = pl.figure(figsize=(10, 8))
ax = fig.add_subplot(111, projection=map_proj)
ax.set_boundary(circle, transform=ax.transAxes)

pm = swp.DBZH.wradlib.plot_ppi(proj=map_proj, ax=ax)
ax = pl.gca()
ax.gridlines(crs=map_proj)

[13]:

<cartopy.mpl.gridliner.Gridliner at 0x7f3d352946d0>

../../_images/notebooks_fileio_wradlib_gamic_backend_20_1.png

[14]:

fig = pl.figure(figsize=(10, 8))
proj = ccrs.AzimuthalEquidistant(
    central_latitude=swp.latitude.values, central_longitude=swp.longitude.values
)
ax = fig.add_subplot(111, projection=proj)
pm = swp.DBZH.wradlib.plot_ppi(ax=ax)
ax.gridlines()

[14]:

<cartopy.mpl.gridliner.Gridliner at 0x7f3d35297a10>

../../_images/notebooks_fileio_wradlib_gamic_backend_21_1.png

[15]:

swp.DBZH.wradlib.plot_ppi()

[15]:

<matplotlib.collections.QuadMesh at 0x7f3d340cd550>

../../_images/notebooks_fileio_wradlib_gamic_backend_22_1.png

Inspect radar moments#

The DataArrays can be accessed by key or by attribute. Each DataArray has dimensions and coordinates of it’s parent dataset. There are attributes connected which are defined by ODIM_H5 standard.

[16]:

display(swp.DBZH)

<xarray.DataArray 'DBZH' (azimuth: 360, range: 360)>
array([[13.177166, 11.671261, 19.200787, ...,       nan,       nan,       nan],
       [11.169292, 11.671261, 17.192913, ...,       nan,       nan,       nan],
       [12.173229, 11.671261, 19.702755, ...,       nan,       nan,       nan],
       ...,
       [10.165356, 11.169292, 19.702755, ...,       nan,       nan,       nan],
       [11.169292, 11.671261, 16.188976, ...,       nan,       nan,       nan],
       [12.173229, 12.675198, 19.200787, ...,       nan,       nan,       nan]],
      dtype=float32)
Coordinates: (12/15)
  * azimuth     (azimuth) float64 0.5 1.5 2.5 3.5 ... 356.5 357.5 358.5 359.5
  * range       (range) float32 50.0 150.0 250.0 ... 3.585e+04 3.595e+04
    elevation   (azimuth) float64 28.0 28.0 28.0 28.0 ... 28.0 28.0 28.0 28.0
    rtime       (azimuth) datetime64[ns] 2018-06-01T05:40:57.362999808 ... 20...
    sweep_mode  <U20 'azimuth_surveillance'
    longitude   float64 6.457
    ...          ...
    x           (azimuth, range) float64 0.3852 1.156 1.926 ... -275.7 -276.4
    y           (azimuth, range) float64 44.14 132.4 ... 3.159e+04 3.168e+04
    z           (azimuth, range) float64 333.5 380.4 ... 1.72e+04 1.725e+04
    gr          (azimuth, range) float64 44.15 132.4 ... 3.159e+04 3.168e+04
    rays        (azimuth, range) float64 0.5 0.5 0.5 0.5 ... 359.5 359.5 359.5
    bins        (azimuth, range) float32 50.0 150.0 ... 3.585e+04 3.595e+04
Attributes:
    format:         UV8
    is_dft:         0
    unit:           dBZ
    long_name:      Equivalent reflectivity factor H
    standard_name:  radar_equivalent_reflectivity_factor_h
    units:          dBZ
    _Undetect:      0.0
    coordinates:    elevation azimuth range latitude longitude altitude time ...

xarray.DataArray

'DBZH'

azimuth: 360
range: 360

13.18 11.67 19.2 18.7 22.71 21.71 19.7 ... nan nan nan nan nan nan nan

array([[13.177166, 11.671261, 19.200787, ...,       nan,       nan,       nan],
       [11.169292, 11.671261, 17.192913, ...,       nan,       nan,       nan],
       [12.173229, 11.671261, 19.702755, ...,       nan,       nan,       nan],
       ...,
       [10.165356, 11.169292, 19.702755, ...,       nan,       nan,       nan],
       [11.169292, 11.671261, 16.188976, ...,       nan,       nan,       nan],
       [12.173229, 12.675198, 19.200787, ...,       nan,       nan,       nan]],
      dtype=float32)

Coordinates: (15)

azimuth
(azimuth)
float64
0.5 1.5 2.5 ... 357.5 358.5 359.5
standard_name :
ray_azimuth_angle
long_name :
azimuth_angle_from_true_north
units :
degrees
axis :
radial_azimuth_coordinate
```
array([  0.5,   1.5,   2.5, ..., 357.5, 358.5, 359.5])
```
range
(range)
float32
50.0 150.0 ... 3.585e+04 3.595e+04
units :
meters
standard_name :
projection_range_coordinate
long_name :
range_to_measurement_volume
axis :
radial_range_coordinate
meters_between_gates :
100.0
spacing_is_constant :
true
meters_to_center_of_first_gate :
50.0
```
array([   50.,   150.,   250., ..., 35750., 35850., 35950.], dtype=float32)
```
elevation
(azimuth)
float64
28.0 28.0 28.0 ... 28.0 28.0 28.0
standard_name :
ray_elevation_angle
long_name :
elevation_angle_from_horizontal_plane
units :
degrees
axis :
radial_elevation_coordinate
```
array([27.998657, 27.998657, 27.998657, ..., 27.998657, 27.998657, 27.998657])
```

rtime

(azimuth)

datetime64[ns]

2018-06-01T05:40:57.362999808 .....

standard_name :: time

array(['2018-06-01T05:40:57.362999808', '2018-06-01T05:40:57.398999808',
       '2018-06-01T05:40:57.435000064', ..., '2018-06-01T05:40:57.256000000',
       '2018-06-01T05:40:57.292000000', '2018-06-01T05:40:57.326999808'],
      dtype='datetime64[ns]')

sweep_mode

()

<U20

'azimuth_surveillance'

array('azimuth_surveillance', dtype='<U20')

longitude
()
float64
6.457
long_name :
longitude
units :
degrees_east
standard_name :
longitude
```
array(6.456949)
```
latitude
()
float64
50.93
long_name :
latitude
units :
degrees_north
positive :
up
standard_name :
latitude
```
array(50.928727)
```
altitude
()
float64
310.0
long_name :
altitude
units :
meters
standard_name :
altitude
```
array(310.)
```

time

()

datetime64[ns]

2018-06-01T05:40:47.076999936

array('2018-06-01T05:40:47.076999936', dtype='datetime64[ns]')

(azimuth, range)

float64

0.3852 1.156 ... -275.7 -276.4

array([[ 3.85243340e-01,  1.15572363e+00,  1.92619539e+00, ...,
         2.74904895e+02,  2.75672328e+02,  2.76439754e+02],
       [ 1.15561267e+00,  3.46681884e+00,  5.77799944e+00, ...,
         8.24630946e+02,  8.26933013e+02,  8.29235054e+02],
       [ 1.92562999e+00,  5.77685802e+00,  9.62804345e+00, ...,
         1.37410581e+03,  1.37794181e+03,  1.38177776e+03],
       ...,
       [-1.92562999e+00, -5.77685802e+00, -9.62804345e+00, ...,
        -1.37410581e+03, -1.37794181e+03, -1.38177776e+03],
       [-1.15561267e+00, -3.46681884e+00, -5.77799944e+00, ...,
        -8.24630946e+02, -8.26933013e+02, -8.29235054e+02],
       [-3.85243340e-01, -1.15572363e+00, -1.92619539e+00, ...,
        -2.74904895e+02, -2.75672328e+02, -2.76439754e+02]])

(azimuth, range)

float64

44.14 132.4 ... 3.159e+04 3.168e+04

array([[   44.14451428,   132.43281034,   220.72012977, ...,
        31500.98083157, 31588.92000067, 31676.85820171],
       [   44.13106743,   132.39247003,   220.65289628, ...,
        31491.38532766, 31579.29770963, 31667.20912384],
       [   44.10417784,   132.31180168,   220.51844978, ...,
        31472.1972427 , 31560.05605859, 31647.91390731],
       ...,
       [   44.10417784,   132.31180168,   220.51844978, ...,
        31472.1972427 , 31560.05605859, 31647.91390731],
       [   44.13106743,   132.39247003,   220.65289628, ...,
        31491.38532766, 31579.29770963, 31667.20912384],
       [   44.14451428,   132.43281034,   220.72012977, ...,
        31500.98083157, 31588.92000067, 31676.85820171]])

(azimuth, range)

float64

333.5 380.4 ... 1.72e+04 1.725e+04

array([[  333.45971573,   380.40454469,   427.34911045, ...,
        17151.26201347, 17198.60832619, 17245.95256648],
       [  333.45971573,   380.40454469,   427.34911045, ...,
        17151.26201347, 17198.60832619, 17245.95256648],
       [  333.45971573,   380.40454469,   427.34911045, ...,
        17151.26201347, 17198.60832619, 17245.95256648],
       ...,
       [  333.45971573,   380.40454469,   427.34911045, ...,
        17151.26201347, 17198.60832619, 17245.95256648],
       [  333.45971573,   380.40454469,   427.34911045, ...,
        17151.26201347, 17198.60832619, 17245.95256648],
       [  333.45971573,   380.40454469,   427.34911045, ...,
        17151.26201347, 17198.60832619, 17245.95256648]])

(azimuth, range)

float64

44.15 132.4 ... 3.159e+04 3.168e+04

array([[   44.14619523,   132.43785317,   220.72853444, ...,
        31502.18033807, 31590.12285575, 31678.06440534],
       [   44.14619523,   132.43785317,   220.72853444, ...,
        31502.18033807, 31590.12285575, 31678.06440534],
       [   44.14619523,   132.43785317,   220.72853444, ...,
        31502.18033807, 31590.12285575, 31678.06440534],
       ...,
       [   44.14619523,   132.43785317,   220.72853444, ...,
        31502.18033807, 31590.12285575, 31678.06440534],
       [   44.14619523,   132.43785317,   220.72853444, ...,
        31502.18033807, 31590.12285575, 31678.06440534],
       [   44.14619523,   132.43785317,   220.72853444, ...,
        31502.18033807, 31590.12285575, 31678.06440534]])

rays

(azimuth, range)

float64

0.5 0.5 0.5 ... 359.5 359.5 359.5

array([[  0.5,   0.5,   0.5, ...,   0.5,   0.5,   0.5],
       [  1.5,   1.5,   1.5, ...,   1.5,   1.5,   1.5],
       [  2.5,   2.5,   2.5, ...,   2.5,   2.5,   2.5],
       ...,
       [357.5, 357.5, 357.5, ..., 357.5, 357.5, 357.5],
       [358.5, 358.5, 358.5, ..., 358.5, 358.5, 358.5],
       [359.5, 359.5, 359.5, ..., 359.5, 359.5, 359.5]])

bins

(azimuth, range)

float32

50.0 150.0 ... 3.585e+04 3.595e+04

array([[   50.,   150.,   250., ..., 35750., 35850., 35950.],
       [   50.,   150.,   250., ..., 35750., 35850., 35950.],
       [   50.,   150.,   250., ..., 35750., 35850., 35950.],
       ...,
       [   50.,   150.,   250., ..., 35750., 35850., 35950.],
       [   50.,   150.,   250., ..., 35750., 35850., 35950.],
       [   50.,   150.,   250., ..., 35750., 35850., 35950.]],
      dtype=float32)

Indexes: (2)

azimuth

PandasIndex

PandasIndex(Float64Index([  0.5,   1.5,   2.5,   3.5,   4.5,   5.5,   6.5,   7.5,   8.5,
                9.5,
              ...
              350.5, 351.5, 352.5, 353.5, 354.5, 355.5, 356.5, 357.5, 358.5,
              359.5],
             dtype='float64', name='azimuth', length=360))

range

PandasIndex

PandasIndex(Float64Index([   50.0,   150.0,   250.0,   350.0,   450.0,   550.0,   650.0,
                750.0,   850.0,   950.0,
              ...
              35050.0, 35150.0, 35250.0, 35350.0, 35450.0, 35550.0, 35650.0,
              35750.0, 35850.0, 35950.0],
             dtype='float64', name='range', length=360))

Attributes: (8)
format :
UV8
is_dft :
0
unit :
dBZ
long_name :
Equivalent reflectivity factor H
standard_name :
radar_equivalent_reflectivity_factor_h
units :
dBZ
_Undetect :
0.0
coordinates :
elevation azimuth range latitude longitude altitude time rtime sweep_mode

Create simple plot#

Using xarray features a simple plot can be created like this. Note the sortby('rtime') method, which sorts the radials by time.

[17]:

swp.DBZH.sortby("rtime").plot(x="range", y="rtime", add_labels=False)

[17]:

<matplotlib.collections.QuadMesh at 0x7f3d2dd10650>

../../_images/notebooks_fileio_wradlib_gamic_backend_26_1.png

[18]:

fig = pl.figure(figsize=(5, 5))
pm = swp.DBZH.wradlib.plot_ppi(proj={"latmin": 3e3}, fig=fig)

../../_images/notebooks_fileio_wradlib_gamic_backend_27_0.png

Mask some values#

[19]:

swp["DBZH"] = swp["DBZH"].where(swp["DBZH"] >= 0)
swp["DBZH"].plot()

[19]:

<matplotlib.collections.QuadMesh at 0x7f3d2ddbe850>

../../_images/notebooks_fileio_wradlib_gamic_backend_29_1.png

Export to ODIM and CfRadial2#

[20]:

vol.to_odim("gamic_as_odim.h5")
vol.to_cfradial2("gamic_as_cfradial2.nc")

[21]:

vol[0]

[21]:

<xarray.Dataset>
Dimensions:            (azimuth: 360, range: 360)
Coordinates:
  * azimuth            (azimuth) float64 0.5 1.5 2.5 3.5 ... 357.5 358.5 359.5
  * range              (range) float32 50.0 150.0 250.0 ... 3.585e+04 3.595e+04
    elevation          (azimuth) float64 ...
    rtime              (azimuth) datetime64[ns] 2018-06-01T05:40:57.362999808...
    sweep_mode         <U20 ...
    longitude          float64 ...
    latitude           float64 ...
    altitude           float64 ...
    time               datetime64[ns] 2018-06-01T05:40:47.076999936
Data variables: (12/16)
    DBZH               (azimuth, range) float32 ...
    DBZV               (azimuth, range) float32 ...
    KDP                (azimuth, range) float32 ...
    RHOHV              (azimuth, range) float32 ...
    DBTH               (azimuth, range) float32 ...
    DBTV               (azimuth, range) float32 ...
    ...                 ...
    WRADV              (azimuth, range) float32 ...
    PHIDP              (azimuth, range) float32 ...
    sweep_number       int64 ...
    prt_mode           <U7 ...
    follow_mode        <U7 ...
    sweep_fixed_angle  float64 28.0
Attributes:
    fixed_angle:  28.0

xarray.Dataset

Dimensions:
- azimuth: 360
- range: 360
Coordinates: (9)
- azimuth
  (azimuth)
  float64
  0.5 1.5 2.5 ... 357.5 358.5 359.5
  standard_name :
  ray_azimuth_angle
  long_name :
  azimuth_angle_from_true_north
  units :
  degrees
  axis :
  radial_azimuth_coordinate
```
array([  0.5,   1.5,   2.5, ..., 357.5, 358.5, 359.5])
```
- range
  (range)
  float32
  50.0 150.0 ... 3.585e+04 3.595e+04
  units :
  meters
  standard_name :
  projection_range_coordinate
  long_name :
  range_to_measurement_volume
  axis :
  radial_range_coordinate
  meters_between_gates :
  100.0
  spacing_is_constant :
  true
  meters_to_center_of_first_gate :
  50.0
```
array([   50.,   150.,   250., ..., 35750., 35850., 35950.], dtype=float32)
```
- elevation
  (azimuth)
  float64
  ...
  standard_name :
  ray_elevation_angle
  long_name :
  elevation_angle_from_horizontal_plane
  units :
  degrees
  axis :
  radial_elevation_coordinate
```
[360 values with dtype=float64]
```
- rtime
  (azimuth)
  datetime64[ns]
  2018-06-01T05:40:57.362999808 .....
  standard_name :
  time
```
array(['2018-06-01T05:40:57.362999808', '2018-06-01T05:40:57.398999808',
       '2018-06-01T05:40:57.435000064', ..., '2018-06-01T05:40:57.256000000',
       '2018-06-01T05:40:57.292000000', '2018-06-01T05:40:57.326999808'],
      dtype='datetime64[ns]')
```
- sweep_mode
  ()
  <U20
  ...
```
[1 values with dtype=<U20]
```
- longitude
  ()
  float64
  ...
  long_name :
  longitude
  units :
  degrees_east
  standard_name :
  longitude
```
[1 values with dtype=float64]
```
- latitude
  ()
  float64
  ...
  long_name :
  latitude
  units :
  degrees_north
  positive :
  up
  standard_name :
  latitude
```
[1 values with dtype=float64]
```
- altitude
  ()
  float64
  ...
  long_name :
  altitude
  units :
  meters
  standard_name :
  altitude
```
[1 values with dtype=float64]
```
- time
  ()
  datetime64[ns]
  2018-06-01T05:40:47.076999936
```
array('2018-06-01T05:40:47.076999936', dtype='datetime64[ns]')
```
Data variables: (16)
- DBZH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Equivalent reflectivity factor H
  standard_name :
  radar_equivalent_reflectivity_factor_h
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- DBZV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Equivalent reflectivity factor V
  standard_name :
  radar_equivalent_reflectivity_factor_v
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- KDP
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  deg/km
  long_name :
  Specific differential phase HV
  standard_name :
  radar_specific_differential_phase_hv
  units :
  degrees per kilometer
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- RHOHV
  (azimuth, range)
  float32
  ...
  format :
  UV16
  is_dft :
  0
  long_name :
  Correlation coefficient HV
  standard_name :
  radar_correlation_coefficient_hv
  units :
  unitless
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- DBTH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Total power H (uncorrected reflectivity)
  standard_name :
  radar_equivalent_reflectivity_factor_h
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- DBTV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Total power V (uncorrected reflectivity)
  standard_name :
  radar_equivalent_reflectivity_factor_v
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- ZDR
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dB
  long_name :
  Log differential reflectivity H/V
  standard_name :
  radar_differential_reflectivity_hv
  units :
  dB
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- VRADH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Radial velocity of scatterers away from instrument H
  standard_name :
  radial_velocity_of_scatterers_away_from_instrument_h
  units :
  meters per seconds
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- VRADV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Radial velocity of scatterers away from instrument V
  standard_name :
  radial_velocity_of_scatterers_away_from_instrument_v
  units :
  meters per second
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- WRADH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Doppler spectrum width H
  standard_name :
  radar_doppler_spectrum_width_h
  units :
  meters per seconds
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- WRADV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Doppler spectrum width V
  standard_name :
  radar_doppler_spectrum_width_v
  units :
  meters per second
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- PHIDP
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  deg
  long_name :
  Differential phase HV
  standard_name :
  radar_differential_phase_hv
  units :
  degrees
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[129600 values with dtype=float32]
```
- sweep_number
  ()
  int64
  ...
```
[1 values with dtype=int64]
```
- prt_mode
  ()
  <U7
  ...
```
[1 values with dtype=<U7]
```
- follow_mode
  ()
  <U7
  ...
```
[1 values with dtype=<U7]
```
- sweep_fixed_angle
  ()
  float64
  28.0
```
array(28.)
```

Indexes: (2)

azimuth

PandasIndex

PandasIndex(Float64Index([  0.5,   1.5,   2.5,   3.5,   4.5,   5.5,   6.5,   7.5,   8.5,
                9.5,
              ...
              350.5, 351.5, 352.5, 353.5, 354.5, 355.5, 356.5, 357.5, 358.5,
              359.5],
             dtype='float64', name='azimuth', length=360))

range

PandasIndex

PandasIndex(Float64Index([   50.0,   150.0,   250.0,   350.0,   450.0,   550.0,   650.0,
                750.0,   850.0,   950.0,
              ...
              35050.0, 35150.0, 35250.0, 35350.0, 35450.0, 35550.0, 35650.0,
              35750.0, 35850.0, 35950.0],
             dtype='float64', name='range', length=360))

Attributes: (1)
fixed_angle :
28.0

Import again#

[22]:

vola = wrl.io.open_odim_dataset("gamic_as_odim.h5")

[23]:

volb = wrl.io.open_cfradial2_dataset("gamic_as_cfradial2.nc")

Check equality#

[24]:

xr.testing.assert_allclose(vol.root, vola.root)
xr.testing.assert_equal(vol[0], vola[0])
xr.testing.assert_allclose(vol.root, volb.root)
xr.testing.assert_equal(vol[0], volb[0])
xr.testing.assert_allclose(vola.root, volb.root)
xr.testing.assert_equal(vola[0], volb[0])

More GAMIC loading mechanisms#

Use `xr.open_dataset` to retrieve explicit group#

Warning

Since \(\omega radlib\) version 1.18 the xarray backend engines for polar radar data have been renamed and prepended with wradlib- (eg. gamic -> wradlib-gamic). This was necessary to avoid clashes with the new xradar-package, which will eventually replace the wradlib engines. Users have to make sure to check which engine to use for their use-case when using xarray.open_dataset. Users might install and test xradar, and check if it is already robust enough for their use-cases (by using xradar’s engine="gamic".

Since \(\omega radlib\) version 1.19 the xarray backend engines for polar radar data have been deprecated. The functionality is kept until wradlib version 2.0, when the backend-code will be removed completely. wradlib is importing that functionality from xradar-package whenever and wherever necessary.

Below we use a compatibility layer in wradlib to give users the chance to adapt their code. The first minimal change is that for every backend the group-layout is conforming to the CfRadial-standard naming scheme (sweep_0, sweep_1, etc.).

Below you can inspect the main differences of the wradlib compatibility layer and the plain xradar implementation.

use wradlib compatibility layer#

[25]:

swp_a = xr.open_dataset(
    f, engine="wradlib-gamic", group="sweep_9", backend_kwargs=dict(reindex_angle=False)
)
display(swp_a)

<xarray.Dataset>
Dimensions:            (azimuth: 360, range: 1000)
Coordinates:
  * azimuth            (azimuth) float64 0.5109 1.519 2.519 ... 358.5 359.5
    elevation          (azimuth) float64 ...
    rtime              (azimuth) datetime64[ns] ...
  * range              (range) float32 75.0 225.0 375.0 ... 1.498e+05 1.499e+05
    sweep_mode         <U20 ...
    longitude          float64 ...
    latitude           float64 ...
    altitude           float64 ...
    time               datetime64[ns] ...
Data variables: (12/16)
    DBZH               (azimuth, range) float32 ...
    DBZV               (azimuth, range) float32 ...
    KDP                (azimuth, range) float32 ...
    RHOHV              (azimuth, range) float32 ...
    DBTH               (azimuth, range) float32 ...
    DBTV               (azimuth, range) float32 ...
    ...                 ...
    WRADV              (azimuth, range) float32 ...
    PHIDP              (azimuth, range) float32 ...
    sweep_number       int64 ...
    prt_mode           <U7 ...
    follow_mode        <U7 ...
    sweep_fixed_angle  float64 ...
Attributes:
    fixed_angle:  0.6

xarray.Dataset

Dimensions:
- azimuth: 360
- range: 1000
Coordinates: (9)
- azimuth
  (azimuth)
  float64
  0.5109 1.519 2.519 ... 358.5 359.5
  standard_name :
  ray_azimuth_angle
  long_name :
  azimuth_angle_from_true_north
  units :
  degrees
  axis :
  radial_azimuth_coordinate
```
array([  0.510864,   1.51886 ,   2.518616, ..., 357.511597, 358.511353,
       359.505615])
```
- elevation
  (azimuth)
  float64
  ...
  standard_name :
  ray_elevation_angle
  long_name :
  elevation_angle_from_horizontal_plane
  units :
  degrees
  axis :
  radial_elevation_coordinate
```
[360 values with dtype=float64]
```
- rtime
  (azimuth)
  datetime64[ns]
  ...
  standard_name :
  time
```
[360 values with dtype=datetime64[ns]]
```
- range
  (range)
  float32
  75.0 225.0 ... 1.498e+05 1.499e+05
  units :
  meters
  standard_name :
  projection_range_coordinate
  long_name :
  range_to_measurement_volume
  axis :
  radial_range_coordinate
  meters_between_gates :
  150.0
  spacing_is_constant :
  true
  meters_to_center_of_first_gate :
  75.0
```
array([7.50000e+01, 2.25000e+02, 3.75000e+02, ..., 1.49625e+05, 1.49775e+05,
       1.49925e+05], dtype=float32)
```
- sweep_mode
  ()
  <U20
  ...
```
[1 values with dtype=<U20]
```
- longitude
  ()
  float64
  ...
  long_name :
  longitude
  units :
  degrees_east
  standard_name :
  longitude
```
[1 values with dtype=float64]
```
- latitude
  ()
  float64
  ...
  long_name :
  latitude
  units :
  degrees_north
  positive :
  up
  standard_name :
  latitude
```
[1 values with dtype=float64]
```
- altitude
  ()
  float64
  ...
  long_name :
  altitude
  units :
  meters
  standard_name :
  altitude
```
[1 values with dtype=float64]
```
- time
  ()
  datetime64[ns]
  ...
```
[1 values with dtype=datetime64[ns]]
```
Data variables: (16)
- DBZH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Equivalent reflectivity factor H
  standard_name :
  radar_equivalent_reflectivity_factor_h
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- DBZV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Equivalent reflectivity factor V
  standard_name :
  radar_equivalent_reflectivity_factor_v
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- KDP
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  deg/km
  long_name :
  Specific differential phase HV
  standard_name :
  radar_specific_differential_phase_hv
  units :
  degrees per kilometer
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- RHOHV
  (azimuth, range)
  float32
  ...
  format :
  UV16
  is_dft :
  0
  long_name :
  Correlation coefficient HV
  standard_name :
  radar_correlation_coefficient_hv
  units :
  unitless
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- DBTH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Total power H (uncorrected reflectivity)
  standard_name :
  radar_equivalent_reflectivity_factor_h
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- DBTV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Total power V (uncorrected reflectivity)
  standard_name :
  radar_equivalent_reflectivity_factor_v
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- ZDR
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dB
  long_name :
  Log differential reflectivity H/V
  standard_name :
  radar_differential_reflectivity_hv
  units :
  dB
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- VRADH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Radial velocity of scatterers away from instrument H
  standard_name :
  radial_velocity_of_scatterers_away_from_instrument_h
  units :
  meters per seconds
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- VRADV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Radial velocity of scatterers away from instrument V
  standard_name :
  radial_velocity_of_scatterers_away_from_instrument_v
  units :
  meters per second
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- WRADH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Doppler spectrum width H
  standard_name :
  radar_doppler_spectrum_width_h
  units :
  meters per seconds
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- WRADV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Doppler spectrum width V
  standard_name :
  radar_doppler_spectrum_width_v
  units :
  meters per second
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- PHIDP
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  deg
  long_name :
  Differential phase HV
  standard_name :
  radar_differential_phase_hv
  units :
  degrees
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- sweep_number
  ()
  int64
  ...
```
[1 values with dtype=int64]
```
- prt_mode
  ()
  <U7
  ...
```
[1 values with dtype=<U7]
```
- follow_mode
  ()
  <U7
  ...
```
[1 values with dtype=<U7]
```
- sweep_fixed_angle
  ()
  float64
  ...
```
[1 values with dtype=float64]
```

Indexes: (2)

azimuth

PandasIndex

PandasIndex(Float64Index([   0.5108642578125,   1.51885986328125,   2.51861572265625,
                        3.515625,    4.5208740234375,      5.51513671875,
                  6.514892578125,       7.5146484375,     8.514404296875,
                   9.51416015625,
              ...
              350.51605224609375,  351.5130615234375, 352.51556396484375,
               353.5125732421875, 354.51507568359375,  355.5120849609375,
              356.50909423828125,  357.5115966796875,  358.5113525390625,
                359.505615234375],
             dtype='float64', name='azimuth', length=360))

range

PandasIndex

PandasIndex(Float64Index([    75.0,    225.0,    375.0,    525.0,    675.0,    825.0,
                 975.0,   1125.0,   1275.0,   1425.0,
              ...
              148575.0, 148725.0, 148875.0, 149025.0, 149175.0, 149325.0,
              149475.0, 149625.0, 149775.0, 149925.0],
             dtype='float64', name='range', length=1000))

Attributes: (1)
fixed_angle :
0.6

use xradar backend#

[26]:

swp_b = xr.open_dataset(
    f, engine="gamic", group="sweep_9", backend_kwargs=dict(reindex_angle=False)
)
display(swp_b)

<xarray.Dataset>
Dimensions:            (azimuth: 360, range: 1000)
Coordinates:
  * azimuth            (azimuth) float64 0.5109 1.519 2.519 ... 358.5 359.5
    elevation          (azimuth) float64 ...
    time               (azimuth) datetime64[ns] ...
  * range              (range) float32 75.0 225.0 375.0 ... 1.498e+05 1.499e+05
    longitude          float64 ...
    latitude           float64 ...
    altitude           float64 ...
Data variables: (12/17)
    DBZH               (azimuth, range) float32 ...
    DBZV               (azimuth, range) float32 ...
    KDP                (azimuth, range) float32 ...
    RHOHV              (azimuth, range) float32 ...
    DBTH               (azimuth, range) float32 ...
    DBTV               (azimuth, range) float32 ...
    ...                 ...
    PHIDP              (azimuth, range) float32 ...
    sweep_mode         <U20 ...
    sweep_number       int64 ...
    prt_mode           <U7 ...
    follow_mode        <U7 ...
    sweep_fixed_angle  float64 ...

xarray.Dataset

Dimensions:
- azimuth: 360
- range: 1000
Coordinates: (7)
- azimuth
  (azimuth)
  float64
  0.5109 1.519 2.519 ... 358.5 359.5
  standard_name :
  ray_azimuth_angle
  long_name :
  azimuth_angle_from_true_north
  units :
  degrees
  axis :
  radial_azimuth_coordinate
```
array([  0.510864,   1.51886 ,   2.518616, ..., 357.511597, 358.511353,
       359.505615])
```
- elevation
  (azimuth)
  float64
  ...
  standard_name :
  ray_elevation_angle
  long_name :
  elevation_angle_from_horizontal_plane
  units :
  degrees
  axis :
  radial_elevation_coordinate
```
[360 values with dtype=float64]
```
- time
  (azimuth)
  datetime64[ns]
  ...
  standard_name :
  time
```
[360 values with dtype=datetime64[ns]]
```
- range
  (range)
  float32
  75.0 225.0 ... 1.498e+05 1.499e+05
  units :
  meters
  standard_name :
  projection_range_coordinate
  long_name :
  range_to_measurement_volume
  axis :
  radial_range_coordinate
  meters_between_gates :
  150.0
  spacing_is_constant :
  true
  meters_to_center_of_first_gate :
  75.0
```
array([7.50000e+01, 2.25000e+02, 3.75000e+02, ..., 1.49625e+05, 1.49775e+05,
       1.49925e+05], dtype=float32)
```
- longitude
  ()
  float64
  ...
  long_name :
  longitude
  units :
  degrees_east
  standard_name :
  longitude
```
[1 values with dtype=float64]
```
- latitude
  ()
  float64
  ...
  long_name :
  latitude
  units :
  degrees_north
  positive :
  up
  standard_name :
  latitude
```
[1 values with dtype=float64]
```
- altitude
  ()
  float64
  ...
  long_name :
  altitude
  units :
  meters
  standard_name :
  altitude
```
[1 values with dtype=float64]
```
Data variables: (17)
- DBZH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Equivalent reflectivity factor H
  standard_name :
  radar_equivalent_reflectivity_factor_h
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- DBZV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Equivalent reflectivity factor V
  standard_name :
  radar_equivalent_reflectivity_factor_v
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- KDP
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  deg/km
  long_name :
  Specific differential phase HV
  standard_name :
  radar_specific_differential_phase_hv
  units :
  degrees per kilometer
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- RHOHV
  (azimuth, range)
  float32
  ...
  format :
  UV16
  is_dft :
  0
  long_name :
  Correlation coefficient HV
  standard_name :
  radar_correlation_coefficient_hv
  units :
  unitless
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- DBTH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Total power H (uncorrected reflectivity)
  standard_name :
  radar_equivalent_reflectivity_factor_h
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- DBTV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dBZ
  long_name :
  Total power V (uncorrected reflectivity)
  standard_name :
  radar_equivalent_reflectivity_factor_v
  units :
  dBZ
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- ZDR
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  dB
  long_name :
  Log differential reflectivity H/V
  standard_name :
  radar_differential_reflectivity_hv
  units :
  dB
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- VRADH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Radial velocity of scatterers away from instrument H
  standard_name :
  radial_velocity_of_scatterers_away_from_instrument_h
  units :
  meters per seconds
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- VRADV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Radial velocity of scatterers away from instrument V
  standard_name :
  radial_velocity_of_scatterers_away_from_instrument_v
  units :
  meters per second
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- WRADH
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Doppler spectrum width H
  standard_name :
  radar_doppler_spectrum_width_h
  units :
  meters per seconds
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- WRADV
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  m/s
  long_name :
  Doppler spectrum width V
  standard_name :
  radar_doppler_spectrum_width_v
  units :
  meters per second
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- PHIDP
  (azimuth, range)
  float32
  ...
  format :
  UV8
  is_dft :
  0
  unit :
  deg
  long_name :
  Differential phase HV
  standard_name :
  radar_differential_phase_hv
  units :
  degrees
  _Undetect :
  0.0
  coordinates :
  elevation azimuth range latitude longitude altitude time rtime sweep_mode
```
[360000 values with dtype=float32]
```
- sweep_mode
  ()
  <U20
  ...
```
[1 values with dtype=<U20]
```
- sweep_number
  ()
  int64
  ...
```
[1 values with dtype=int64]
```
- prt_mode
  ()
  <U7
  ...
```
[1 values with dtype=<U7]
```
- follow_mode
  ()
  <U7
  ...
```
[1 values with dtype=<U7]
```
- sweep_fixed_angle
  ()
  float64
  ...
```
[1 values with dtype=float64]
```

Indexes: (2)

azimuth

PandasIndex

PandasIndex(Float64Index([   0.5108642578125,   1.51885986328125,   2.51861572265625,
                        3.515625,    4.5208740234375,      5.51513671875,
                  6.514892578125,       7.5146484375,     8.514404296875,
                   9.51416015625,
              ...
              350.51605224609375,  351.5130615234375, 352.51556396484375,
               353.5125732421875, 354.51507568359375,  355.5120849609375,
              356.50909423828125,  357.5115966796875,  358.5113525390625,
                359.505615234375],
             dtype='float64', name='azimuth', length=360))

range

PandasIndex

PandasIndex(Float64Index([    75.0,    225.0,    375.0,    525.0,    675.0,    825.0,
                 975.0,   1125.0,   1275.0,   1425.0,
              ...
              148575.0, 148725.0, 148875.0, 149025.0, 149175.0, 149325.0,
              149475.0, 149625.0, 149775.0, 149925.0],
             dtype='float64', name='range', length=1000))

Attributes: (0)

xarray GAMIC backend

Contents

xarray GAMIC backend#

Load ODIM_H5 Volume Data#

Inspect RadarVolume#

Inspect root group#

Inspect sweep group(s)#

Goereferencing#

Plotting#

Inspect radar moments#

Create simple plot#

Mask some values#

Export to ODIM and CfRadial2#

Import again#

Check equality#

More GAMIC loading mechanisms#

Use xr.open_dataset to retrieve explicit group#

use wradlib compatibility layer#

use xradar backend#

Use `xr.open_dataset` to retrieve explicit group#