The martian atmosphere in the region of Hellas basin as observed by the planetary Fourier spectrometer (PFS-MEX)

This work presents a review of the observations acquired by the planetary Fourier spectrometer (PFS) in the region of the Hellas basin. Taking advantage of the high spectral resolution of PFS, the vertical air temperature profile can be investigated with a previously unexperienced vertical resolution. Extensive comparisons with the expectations of EMCD 4.0 database highlight moderate discrepancies, strongly dependant on season. Namely, the morning observations acquired around L_s=45° show a series of temperature deficiencies with recurrent spatial patterns in different observations, correlated with the topography profile. Trends of integrated dust loads as a function of the field of view (FOV) elevation are also described. Values are consistent with the retrieval hypothesis of a dust scale height equal to the gas one, even far from the season of main dust storms.