Water vapour abundance in Martian atmosphere from revised Mariner 9 IRIS data

After the correction for the instrumental effect, Mariner-9 IRIS data were analysed to retrieve water vapour abundance in the southern hemisphere in late summer. Seasonal, latitudinal and diurnal variability of water vapour is studied. The major detected effect is the diurnal peak of Hz0 abundance, which decreases during the period from L, =293’ to L, = 345”.