Modeling The Hdo Cycle With A Global Climate Model During The My34 “Dusty” Season.
M. Vals, (Margaux.Vals@Latmos.Ipsl.Fr), L. Rossi, F. Montmessin, F. LefèVre, Laboratoire AtmosphèRes, Milieux,
Observations Spatiales, Paris, Guyancourt, France, F. Gonzalez-Galindo, Instituto De Astrofı́Sica De Andalucı́A-Csic,
Granada, Spain, A. Fedorova, M. Luginin, Space Research Institute (Iki), Moscow, Russia, F. Forget, E. Millour,
Laboratoire De MéTéOrologie Dynamique, Paris, France, O. Korablev, A. Trokhimovskiy, A. Shakun, Space
Research Institute (Iki), Moscow, Russia, A. Bierjon, Laboratoire De MéTéOrologie Dynamique, Paris, France, L.
Montabone, Laboratoire De MéTéOrologie Dynamique, Paris, France, Space Science Institute, Boulder, Co, Usa.

Introduction
The D/H Ratio Observed In A Planetary Atmosphere Is A
Proxy For The Ratio Of The Current Water Reservoir Over
The Initial Water Reservoir Of The Planet. The Current D/H
Ratio Measured In The Martian Atmosphere Is At Least Five
Times That Of The Vienna Standard Mean Ocean Water
(Vsmow) [1],[2],[3],[4]. This High Value Of The Martian D/H Ratio, Derived From The Hdo/H2 O Abundance
Ratio, Is A Precious Indicator Of The Large Escape Of Water
From The Martian Atmosphere Along Time. Apart From The
Mass Difference Between Both Isotopes, The Differential
Escape Of H And D Comes From The Preferential Photolysis Of H2 O Over Hdo [5] And The Vapor Pressure Isotope
Effect (Vpie) That Produces An Isotopic Fractionation At