Strong seasonal and diurnal variability of water D/H on Mars as revealed with ExoMars/NOMAD
Abstract
We present the first complete dataset of retrievals of water and D/H vertical profiles derived from the Nadir and Occultation for MArs Discovery (NOMAD) instrument, onboard ExoMars Trace Gas Orbiter (TGO). These retrievals cover the entire nominal science phase so far, which started on April 21st, 2018. The water isotopic ratio can be used to test for water loss and ancient water reservoirs, yet climatological and short-term processes (e.g., condensation, Rayleigh distillation) can hide and mask the true evolutionary signature of escape isotopic fractionation. This first comprehensive study of the seasonal and diurnal processes affecting this key signature allows us to better separate evolutionary from climatological processes, providing a strong quantification of water loss impressed in the D/H of water on Mars.
- Publication:
-
EPSC-DPS Joint Meeting 2019
- Pub Date:
- September 2019
- Bibcode:
- 2019EPSC...13..725V