Top: same as Figure 6, except showing contours of P-T profile slope derived from the GCM suite of A. Roth et al. (2024a). The black dashed line shows the point at which an isothermal P-T profile is expected, while successively more blue-green (red) colors show successively more strongly decreasing (inverted) P-T profiles. The A. Roth et al. (2024a) GCM grid only covers a limited range of T_eq–g_P space as compared to the observed planets. The solid black lines show our best-fit boundary between inverted and noninverted regimes using a temperature only fit and a temperature and surface gravity fit with a 1σ shaded uncertainty. Bottom: expected volume mixing ratios at a pressure level of 10⁻² bar (approximately the pressure level at which the inversions may occur; Figure 2) of several proposed inversion agents as a function of planetary equilibrium temperature, as calculated with FastChemCond.