OMPS Retrieval¶

class omps.omps_1d_retrieval.OMPSRetrieval(orbitnumber, imagenumber, slitnumber=1, do_simulation=False)¶

Class which handles the full retrieval (using simulatied or real data) for a single OMPS image

Typically, the class is constructed wtih an OMPS orbit and image number. The user then changes any desired options, and finally retrieve_profiles() is called, starting the retrieval.

The option do_simulation, allows the user to switch between retrievals using real or simulated OMPS data.

Parameters:

orbitnumber : int

The OMPS orbit number to retrieve from

imagenumber : int

The OMPS image number to retrieve from

slitnumber : int

the OMPS slit to retrieve from

0 - left slit

1 - center slit

2 - right slit

Examples

A simple retrieval with default settings

>>> omps = OMPSRetrieval( 12115, 40 )
>>> output = omps.retrieve_profile()
>>> plt.plot(output['retrieved','aero'], np.arange(0.5, 100.5))

Retrieve only ozone with single scatter only

>>> omps = OMPSRetrieval( 12115, 40 )
>>> omps.ret_opt['retrieval_order'] = ['ozone']
>>> omps.ret_opt['max_iter'] = [5]
>>> omps.ret_opt['scatterorder'] = [1]
>>> output = omps.retrieve_profiles()

Methods

`HR_options`
`aerosol_apriori`
`albedo_apriori`
`background_atmosphere`
`check_retrieval_options`
`generate_measured_radiances`
`make_meas_inst`
`make_retrieval_inst`
`make_simulation_inst`
`model_full_spectrum`
`model_full_spectrum_using_L2`
`no2_apriori`
`ozone_apriori`
`ozone_convolution_parameters`
`retrieval_options_default`
`retrieve_aerosol`
`retrieve_albedo`
`retrieve_ozone`
`retrieve_particlesize`
`retrieve_profiles`
`setup_simulation_model`
`simulation_options_default`
`version`

check_retrieval_options()¶: Simple check to ensure that the retrieval options match the expected size. If they do not a warning is issued and the defaults are used.

generate_measured_radiances(radtran)¶

Generate the simulated measurements used in the retrieval. Radiances are simulated at the wavelengths needed by the retrieval species.

This is only used in simulated retrievals

make_meas_inst()¶

Make the instrument that generates the measured level 1 data. Data is loaded from the gridded level 1B product provided by NASA-GSFC.

Returns:	meas_inst : `OMPS`

make_retrieval_inst()¶

Make the instrument that generates the simulated level 1 data for the retrieval. This is used to generate the measurement vector, f.

Returns:	ret_inst : `LimbProfiler_scan`

make_simulation_inst()¶

Make the instrument that generates the simulated level 1 data.

Returns:	meas_inst : `LimbProfiler_scan`

model_full_spectrum()¶

Compute the modelled radiance at all wavelengths in the measurement instrument This should be called after a retrieval has been performed.

Returns:

rad : 2darray

An array containg wavelength x radiance

model_full_spectrum_using_L2(wavelengths=None, save_to_file=False)¶

Compute the modelled radiance at all wavelengths in the measurement instrument using ozone, aerosol and albedo values retrieved previously and stored in an output hdf5 file.

Returns:

rad : 2darray

An array containg wavelength x radiance

ozone_convolution_parameters(psf_wavel_nm, psf, samples_wavel_nm, samples)¶

Determines the gaussian stand deviation used to convolve the ozone cross-section before the radiative transfer calculation. Strictly speaking this should be zero, however pre-convolution can greatly speed of radiative transfer calculations.

Returns the gaussian std dev as a function of wavelength based on instrument point spread function and whether or not the radiances are being oversampled.

retrieve_ozone(maxiter)¶: Performs an ozone retrieval using the method, radiative transfer model, and species defined in retrieve_profiles(). Retrieval details are contained in the species class.

retrieve_profiles()¶: The high level retrieval script that puts together the instruments, atmosphere, radiative transfer model and method to retrieve the desired species.

setup_simulation_model(sim_options)¶

Creates a radiative transfer model with the desired options and atmospheric state

Parameters:

sim_opt : dictionary

Contains the sasktran HR settings, ie numdiffuseprofiles, numordersofscatter, etc.

atmospheric_state : dictionary

Contains the type of climatologies used for ozone, no2 and aerosol (labow, pratmo, userdefined, etc) and, if userdefined, their values.

Returns:

radiative transfer model : SasktranHR

Pointer to the radiative transfer model instantiated in c++

atmospheric state : Atmosphere

Instance of an Atmosphere, which holds pointers to the optical properties and climatologies

version()¶

Returns:	the software version number