I have not done much planetary spectroscopy other than to demonstrate the presence of methane bans in the atmospheres of Uranus and Neptune as shown below and to demonstrate, via Doppler shifting of the Ha line, rotation in the rings of Saturn and the disk of Jupiter.
Shown here are graphic representations and spectra which shows rotation of Saturn's rings and rotation of Jupiter.
In both displays, the slit to obtain the spectra was oriented as indicated in upper left hand corner. The raw spectrum for Saturn and Jupiter was then sub-sectioned to display the spectrum of the eastern and then western portions of either the rings or the disk in the case of Jupiter. The spectra were then aligned to easily show the difference in wavelength due to rotation.