Moisture Incrementing Operator

The Moisture Incrementing Operator (MIO) is a linear variable change distributing specific total water and temperature increments into water vapour, cloud liquid water and cloud ice increments, as described in [MLB18].

The mo_super_mio outer block

The mo_super_mio is a super SABER outer block that combines the mo_moistincrop outer block (described below) with the mo_air_temperature outer block, which is required by mo_moistincrop to calculate air temperature increments from Exner and potential temperature increments as well as to perform the left-inverse and adjoint of these calculations. Optionally it is also possible to use the mo_super_mio block with an ensemble of forecast perturbations to generate calibration coefficients for the moisture incrementing operator.

Example yaml

saber outer blocks:
- saber block name: mo_super_mio
  moisture incrementing operator file: testdata/MIO_coefficients.nc
  calibration: # Optional
    coefficient filling value: median
    output file: testdata/error_covariance_training_spectralb_mio/MIO_coefficients_new.nc

The calibration section is needed to perform the direct calibration of the MIO block, and allows to input the coefficient filling value specifying the calibration coefficient to use for the MIO when no calibration data are available for a given model level and total relative humidity bin. The output netcdf file with new calibration coefficients can be specified in output file.

The mo_moistincrop outer block

This block calculates the specific humidity, the cloud liquid water and the cloud ice increments from specific total water and temperature increments [MLB18], as well as the left-inverse and adjoint transformations. This block cannot be calibrated on its own, but only as part of the mo_super_mio block, in which it is nested. During the calibration of the mo_super_mio block, the mo_moistincrop block performs the calculations that are necessary to generate a netcdf file with the MIO calibration coefficients – for a given model level and total relative humidity bin – when the calibration option is present in the mo_super_mio yaml file.