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Assume an isothermal terminator, constant gravity and mean molecular weight, and use the stated nightside atmospheric scale height as the terminator value. Hydrostatic equilibrium gives $P(z)=P_{\mathrm{ref}}{e}^{-(z-z_{\mathrm{ref}})/H}$. A band radius three atmospheric scale heights above a measured continuum at $0.1\mathrm{bar}$ therefore corresponds toThis is the band's characteristic pressure, not automatically the top of an exoplanet cloud deck. The distinction matters because an opaque cloud generally raises the continuum and removes the lower part of a molecular feature; it does not cap the height of a strong molecular line above the cloud.

If the quoted $0.1\mathrm{bar}$ is the actual observed continuum and the cloud dominates its opacity, the consistent estimate is insteadIf $0.1\mathrm{bar}$ refers to a clear-atmosphere reference continuum, an additional clear band height is necessary. Let that height be $NH$. A cloud at height $z_c$ leaves a residual feature of $3H$ when $NH-z_c=3H$. Thus the cloud pressure degeneracy of a transmission feature givesFor example, a $5\mathrm{mbar}$ cloud estimate requires the extra assumption that the clear band spans six scale heights, so the cloud raises the continuum by three. Identifying the cloud with the level three scale heights above the original continuum gives the same numerical value, but is not justified by the observed band height alone. Without a clear-band opacity or equivalent reference radius, there is no unique cloud-top pressure. A strong dayside emission feature also does not supply that missing terminator information.