Fig 3.3.1.13.1: NO2 reference curve fitted to the Ring compensated absorption curve.
Image: AT2-ELS
The reference spectrum for NO2 is now fitted to the absorption curve resulting from the Ring effect compensation.
The reference spectra of trace gases used in the remaining steps of the DOAS procedure were measured in the lab either by the satellite spectrometer itself before launch or with high resolution instruments. The latter data sets are degraded numerically to the spectral resolution of the satellite instrument.