class_docstr: CO2 correction of the brightness temperature of the MSG 3.9um channel.
  
  .. math::
  
    T4_CO2corr = (BT(IR3.9)^4 + Rcorr)^0.25
    Rcorr = BT(IR10.8)^4 - (BT(IR10.8)-dt_CO2)^4
    dt_CO2 = (BT(IR10.8)-BT(IR13.4))/4.0
  
  Derived from D. Rosenfeld, "CO2 Correction of Brightness Temperature of Channel IR3.9"
  References:
      - https://resources.eumetrain.org/IntGuide/PowerPoints/Channels/conversion.ppt
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docstr: Apply correction.
docstr_tok: ["Apply","correction","."]
code: def __call__(self, projectables, optional_datasets=None, **info):
      """Apply correction."""
      ir_039, ir_108, ir_134 = projectables
      logger.info("Applying CO2 correction")
      dt_co2 = (ir_108 - ir_134) / 4.0
      rcorr = ir_108**4 - (ir_108 - dt_co2) ** 4
      t4_co2corr = (ir_039**4 + rcorr).clip(0.0) ** 0.25
  
      t4_co2corr.attrs = ir_039.attrs.copy()
  
      self.apply_modifier_info(ir_039, t4_co2corr)
  
      return t4_co2corr
  
file_path: satpy/satpy/modifiers/atmosphere.py
imports: import logging
  import dask.array
  import numpy
  import xarray
  from satpy.modifiers import ModifierBase
  from satpy.modifiers._crefl import ReflectanceCorrector
  from satpy.modifiers.angles import compute_relative_azimuth, get_angles, get_satellite_zenith_angle
label_desc: Use image node_id 1 for calling the CO2Corrector obj's underlying member method code with example usage: obj.__call__(projectables, optional_datasets) and returns: t4_co2corr