Fig. 10.
The recommended ECT adjustment curves, delta T' vs. Tc, with Tc defined as the average of all 13 ECT sensors. Correction of the ECT to blackbody radiance requires only these curves and no emissivity adjustment. This is not to say that the emissivity of the ECT was unity. Rather, a value of unity has been historically used for the ECT in the GOES program, so these curves lump the combined effects of non-unity emissivity and temperature error into one temperature dependent parameter in order to make the required corrections simpler to implement using the existing GOES calibration algorithms.