Solid lines: true (noiseless) spectra for the three atmospheric configurations in Table 2 at phase angle α = 0°. Symbols: corresponding measured spectra, with error bars specific to S∕N = 10. The size of the error bars (σ_m; see text) is defined on the basis of the brightest spectral bin (which typically occurs near 500 nm) and is the same at all wavelengths for each spectrum. The spectra correspond to no-cloud (light blue), thin-cloud (dark blue), and thick-cloud (purple) atmospheric configurations.