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This Jupyter notebook demonstrates using the cdasws Python package to access NetCDF data from cdaweb with the data returned in the xarray.Dataset. This notebook contains the following sections:
Notes:
Install the prerequisite software from the Python Package Index if it is not already installed.
) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.#%pip install xarray
#%pip install cdflib
#%pip install cdasws
Execute some preliminary code that is necessary before the code that follows.
from cdasws import CdasWs
from cdasws.datarepresentation import DataRepresentation as dr
import matplotlib.pyplot as plt
cdas = CdasWs()
The following code demonstrates how to get the available observatory groups.
obs_groups = cdas.get_observatory_groups()
for index, obs_group in enumerate(obs_groups):
obs_group_name = obs_group['Name']
if 'ICON' in obs_group_name:
print(obs_group_name)
ICON
The following code demontrates how to get a list of datasets.
datasets = cdas.get_datasets(observatoryGroup='ICON')
for index, dataset in enumerate(datasets):
print(dataset['Id'], dataset['Label'])
ICON_L2-1_MIGHTI-A_LOS-WIND-GREEN Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI) Sensor A: Line-of-sight Wind Profiles - T. J. Immel (UC Berkeley>SSL) ICON_L2-1_MIGHTI-A_LOS-WIND-RED Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI) Sensor A: Line-of-sight Wind Profiles - T. J. Immel (UC Berkeley>SSL) ICON_L2-1_MIGHTI-B_LOS-WIND-GREEN Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI) Sensor B - Line-of-sight Wind Profiles - T. J. Immel (UC Berkeley>SSL) ICON_L2-1_MIGHTI-B_LOS-WIND-RED Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI) Sensor B - Line-of-sight Wind Profiles - T. J. Immel (UC Berkeley>SSL) ICON_L2-2_MIGHTI_VECTOR-WIND-GREEN MIGHTI - Cardinal Vector Winds - T. J. Immel (UC Berkeley>SSL) ICON_L2-2_MIGHTI_VECTOR-WIND-RED MIGHTI - Cardinal Vector Winds - T. J. Immel (UC Berkeley>SSL) ICON_L2-3_MIGHTI-A_TEMPERATURE ICON MIGHTI-A Level 2.3 Retrieved Temperature File - T. J. Immel (UC Berkeley>SSL) ICON_L2-3_MIGHTI-B_TEMPERATURE ICON MIGHTI-B Level 2.3 Retrieved Temperature File - T. J. Immel (UC Berkeley>SSL) ICON_L2-4_FUV_DAY ICON FUV Daytime: column density ratio of thermospheric atomic oxygen to molecular nitrogen. - T. J. Immel (UC Berkeley>SSL) ICON_L2-5_FUV_NIGHT FUV Short Wavelength Channel - 135.6 Altitude Profiles (night) - T. J. Immel (UC Berkeley>SSL) ICON_L2-6_EUV ICON EUV derived ionospheric data products - T. J. Immel (UC Berkeley>SSL) ICON_L2-7_IVM-A ICON Ion Velocity Meter (IVM) Thermal Plasma Measurements - T. J. Immel (UC Berkeley>SSL) ICON_L2-7_IVM-B ICON IVM Thermal Plasma Measurements B - T. J. Immel (UC Berkeley>SSL)
The following code demonstrates how to get a dataset's variables.
ds_id = 'ICON_L2-4_FUV_DAY'
var_names = []
variables = cdas.get_variables(ds_id)
for variable in variables:
var_name = variable['Name']
var_names.append(var_name)
print(var_name, variable['LongDescription'])
ICON_L24_1356_Emission Disk short wave emission ICON_L24_Ap Ap used in retreival ICON_L24_Disk_LOS_Zen_Angle Retrieved disk LOS zenith angle ICON_L24_Disk_Latitude Retrieved disk latitude ICON_L24_Disk_Longitude Retrieved disk longitude ICON_L24_Disk_ON2 Retrieved disk column O/N2 ICON_L24_Disk_SZA Retrieved disk SZA ICON_L24_Disk_Sigma_ON2 Retrieved disk column O/N2 uncertainty ICON_L24_LBH_Emission Disk long wave emission
The following code demonstrates how to get NetCDF data from the ICON_L2-4_FUV_DAY dataset.
data = cdas.get_data(ds_id, var_names,
'2022-11-24T23:00:00Z', '2022-11-24T23:05:00Z',
dataRepresentation = dr.XARRAY)[1]
print(data)
<xarray.Dataset>
Dimensions: (Epoch_cdf: 24, record0: 6951)
Coordinates:
* Epoch_cdf (Epoch_cdf) datetime64[ns] 2022-11-24T23:00:...
Dimensions without coordinates: record0
Data variables:
time_base datetime64[ns] 1970-01-01
ICON_L24_1356_Emission (Epoch_cdf) float32 3.69e+03 ... 3.435e+03
ICON_L24_Ap (Epoch_cdf) float32 12.0 12.0 ... 12.0 12.0
ICON_L24_Disk_LOS_Zen_Angle (Epoch_cdf) float32 119.9 119.9 ... 119.9 119.9
ICON_L24_Disk_Latitude (Epoch_cdf) float32 -19.67 -19.66 ... -18.34
ICON_L24_Disk_Longitude (Epoch_cdf) float32 200.5 201.3 ... 217.1 217.8
ICON_L24_Disk_ON2 (Epoch_cdf) float32 0.5691 0.5892 ... 0.5599
ICON_L24_Disk_SZA (Epoch_cdf) float32 8.413 9.165 ... 25.11 25.87
ICON_L24_Disk_Sigma_ON2 (Epoch_cdf) float32 0.01592 0.0184 ... 0.02127
ICON_L24_LBH_Emission (Epoch_cdf) float32 1.038e+03 ... 964.8
Epoch (record0) int64 1669248003023 ... 1669334389316
Attributes:
ACKNOWLEDGEMENT: This is a data product from the NASA Ionosph...
ADID_ref: NASA Contract>NNG12FA45C
CALIBRATION_FILE:
CONVENTIONS: SPDF ISTP/IACG Modified for NetCDF
DATA_LEVEL: L2.4
Data_type: DP24>Data Product 2.4: FUV Daytime
DESCRIPTION: ICON FUV Daytime
Descriptor: ICON FUV Daytime
Discipline: Space Physics>Ionospheric Science
FILE_DATE: 2022-11-23T23:59:57 UTC
GENERATED_BY: ICON FUV L1 > ICON FUV L2v04r000, R. Meier
GENERATION_DATE: Wed Jan 11 02:35:47 2023
HISTORY: Version 003, Frist public release, disk data...
INSTRUMENT: FUV
Instrument_type: Imaging and Remote Sensing (ITM/Earth)
HTTP_LINK: http://icon.ssl.berkeley.edu/
LINK_TEXT: ICON FUV
LINK_TITLE: instrument site
Logical_file_id: icon_l2-4s_fuv_day_20221124230010_2022112423...
Logical_source: ICON_L2-4S_FUV_DAY
Logical_source_description: DERIVED FROM: ICON FUV Daytime: column densi...
Mission_group: ICON
PARENTS: ['ICON_L1_FUV_LWP_2022-11-24_v05r000.NC', 'I...
PI_affiliation: UC Berkeley>SSL
PI_name: T. J. Immel
Project: NASA>ICON
RULES_OF_USE: Public Data for Scientific Use
SOFTWARE_VERSION: ICON SDC > FUV v04r000
Source_name: ICON>Iconospheric Connection Explorer
SPACECRAFT_ID: NASA>ICON - 493
Text: ['CDAWeb interface derived data on Thu Apr ...
TEXT_SUPPLEMENT: This describes the data product for ICON FUV...
TIME_RESOLUTION: 12 Sec
TITLE: ICON FUV Daytime
NCO: netCDF Operators version 4.7.5 (Homepage = h...
NC_KIND: netCDF-4
NC_DIMENSIONS_G: ['Epoch=UNLIMITED', 'Covariance Matrix 2nd D...
NC_STRINGS_G: Acknowledgement ADID_Ref Calibration_File Co...
The following code displays metadata for the ICON_L24_Disk_SZA variable, do
print(data.ICON_L24_Disk_SZA)
<xarray.DataArray 'ICON_L24_Disk_SZA' (Epoch_cdf: 24)>
array([ 8.413165, 9.165311, 9.919736, 10.674797, 11.431073, 12.187651,
12.945468, 13.703261, 14.462048, 15.220608, 15.980153, 16.739532,
17.499659, 18.259481, 19.019903, 19.780228, 20.540913, 21.30163 ,
22.062748, 22.823668, 23.585054, 24.345064, 25.106302, 25.867178],
dtype=float32)
Coordinates:
* Epoch_cdf (Epoch_cdf) datetime64[ns] 2022-11-24T23:00:10.767000 ... 2022...
Attributes:
FIELDNAM: Retrieved disk SZA
NC_DIMENSIONS_V: Epoch
NC_DEFLATE: [6]
NC_SHUFFLE: true
NC_STORAGE: chunked
NC_CHUNKSIZES: [7013]
CATDESC: Retrieved disk SZA
DEPEND_0: Epoch_cdf
DISPLAY_TYPE: time_series
FILLVAL: [-999.]
UNITS: Degrees
VALIDMAX: [180.]
VALIDMIN: [0.]
VAR_NOTES: Solar zenith angle corresponding to disk retrieval
VAR_TYPE: data
NC_STRINGS_V: CatDesc Depend_0 Display_Type FieldNam Long_Name Units ...
DIM_SIZES: [0]
standard_name: Retrieved disk SZA
units: Degrees
The following code plots the ICON_L24_Disk_SZA variable's values using the label values from the metadata.
data['ICON_L24_Disk_SZA'].plot()
[<matplotlib.lines.Line2D at 0x7f258882e7b8>]
View the cdasws API for additional functions. Additional notebook examples are also available.
