Sensitivity of model fits and retrieved surface albedos to methane-mixing ratio and temperature vertical profiles. Top: radiance factor observed in the region of a possible tropical lake (Griffith et al. 2012; Coutelier et al. 2021) over a bright and a dark area. The lines are for the results of the retrieval model, used with the reference set-up and with the modified gas absorption for tests #1 and #2 and with the modified temperature for test #3. The different fits of each spectrum, obtained with different model setups, cannot be distinguished from one another. Bottom: retrieved surface albedo for the bright and the dark pixels for the reference model (black dots) and with the modified gas absorption for tests #1 (red dots), #2 (blue dots), and #3 (pink dots). For clarity, we display the error bars for the reference model only. The error bars obtained with the other models are very similar.