act.retrievals.aeri2irt#

act.retrievals.aeri2irt(aeri_ds, wnum_name='wnum', rad_name='mean_rad', hatch_name='hatchOpen', tolerance=0.1, temp_low=150.0, temp_high=320.0, maxiter=200)[source]#

This function will integrate over the correct wavenumber values to produce the effective IRT temperature.

As a note from the ARM IRT Instrument Handbook A positive bias of the sky temperature is exhibited by the downwelling IRT, compared to the AERI, during clear-sky conditions when the sky temperature is less than ~180K. The effect depends on the characteristics of the individual IRT and the internal reference temperature of the IRT. The greatest difference compared to AERI will occur when the sky is very clear, dry, and cold and the ambient temperature is relatively hot, maximizing the difference in temperature between the sky and instrument, and the calibration of the IRT at the lower limit of 223K was not performed accurately. This bias is especially apparent at high-latitude sites (e.g., NSA, OLI, and AWR).

https://www.arm.gov/publications/tech_reports/handbooks/irt_handbook.pdf

Author - Ken Kehoe

Parameters:

  • aeri_ds (xarray.Dataset) – The xarray dataset containing AERI data.

  • wnum_name (str) – The variable name for coordinate dimention of wave number Xarray Dataset.

  • hatch_name (str or None) – The variable name for hatch status. If set to None will not try to set when hatch is not opent to NaN.

  • rad_name (str) – The variable name for mean radiance in Xarray Dataset.

  • tolerance (float) – The tolerance value to try and match for returned temperature.

  • temp_low (float) – The initial low value to use in zbren function to invert radiances.

  • temp_high (float) – The initial low value to use in zbren function to invert radiances.

  • maxiter (int) – The maximum number if iterations to use with invertion process. Prevents runaway processes.

Returns:

ds (xarray.Dataset or None) – The aeri_ds Dataset with new DataArray of temperatures added under variable name ‘aeri_irt_equiv_temperature’.