Cross-correlation matrices in the Earth’s rest frame for potential H₂O signals in GJ 1214b as a function of the velocity Doppler shifts applied to the template (horizontal axis, full range explored) and the planet’s orbital phase (vertical axis). Results are shown per spectral order (columns) and for each night (rows). The H₂O template employed presented 10× solar metallicity and a 10 mbar cloud deck. The red box marks an excluded spectral order due to uncorrected systematics.