Strength of CO₂ detections at (a) 1.21 μm, (b) 1.44 μm, (c) 1.52 μm, and (d) 1.63 μm with respect to CO₂ abundance and SNR assuming a 20% bandpass. Columns on the x-axis are different CO₂ abundances: Bridging, Proterozoic-like, Archean-like, and Venus-like, from left to right. SNR values are on the y-axis. The strength of detection is shown for each combination of CO₂ abundance and SNR. As indicated by the color bar on the right side of each heat map, the darker the purple is, the stronger the detection is, and the lighter the pink is, the more unconstrained the detection is, following the same lnB classifications defined in Table 2.