Extended Data Fig. 3: Comparison of the estimated impact of fractionation during photolysis for the perihelion and aphelion seasons during MY34 and MY35.
From: Isotopic fractionation of water and its photolytic products in the atmosphere of Mars
a, Calculated H2O dissociation rates, with the colour of the lines representing the latitude of the observations. b, Column-integrated photolysis rates (red dots) as a function of latitude. The yellow dots represent the column-integrated photolysis rates when using the part of the column in which the measurements are sensitive to HDO. c, Fractionation factor R between the D/H ratio representative of water vapour in the lower atmosphere and that of the photolysis products for the cases of photolysis-induced (black line) and condensation-induced fractionation (coloured lines). d, Column-integrated fractionation factor R as a function of latitude for the cases of photolysis-induced (blue dots) and condensation-induced (yellow dots) fractionation, as well as the combination of the two (red dots). The condensation-induced fractionation factor is only plotted if the column-integrated photolysis rate using the part of the column in which the measurements are sensitive to HDO (yellow dots in b) is at least 75% of that calculated when using the whole column (red dots in b).
