Atmospheric forward models compared to eclipse depth measurements using various analyses. Spectra are compared to eclipse depths recovered using aperture extraction with a GP, pixel-fitting or a secondary analysis fit using optimal extraction without a GP. Left: emission spectra of bare rock and pure CO₂ models at varying surface pressures. Statistical significance given relative to joint-fitting aperture extracted light curves using GPs. Right: similar plot for pure H₂O, pure SO₂ or H₂O/CO₂ mixture atmospheres. All atmospheric models account for heat redistribution using the f-factor parameterisation in Koll (2022) and use a surface albedo of A_surf = 0.1.