SPS Seminar - The isotopic composition of Mars’ atmosphere as measured by the ExoMars Trace Gas Orbiter

When:  Thursday 24^th February at 14.00

Where:  Microsoft Teams - Online

Speaker:  Juan Alday (OU)

Hosted by: Chiaki Crews

Abstract:

Isotopic ratios in different atmospheric species provide useful information about the past and present climate on Mars. Overall enrichment in the heavy isotopes of species such as hydrogen, nitrogen, or the noble gases with respect to Earth indicate that Mars has lost a substantial fraction of its atmosphere throughout history, consistent with the idea of a denser and warmer past atmosphere that could sustain liquid water on the surface. On the other hand, variations of the isotopic ratios in the present-day atmosphere can reveal information about the processes that govern the different atmospheric cycles. In this talk, I will provide an overview of the measurements of the isotopic ratios in water vapour and carbon dioxide made by the Atmospheric Chemistry Suite onboard the ExoMars Trace Gas Orbiter. I will explain the characteristics of these observations, followed by the main results, including the variability of the isotope ratios in the present-day atmosphere, as well as the implications these measurements have to our current understanding of the isotopic composition of the Martian atmosphere. 

Bio:

Juan finished his PhD at the University of Oxford in 2021, studying the isotopic composition of Mars’ atmosphere using observations from the Atmospheric Chemistry Suite onboard the ExoMars Trace Gas Orbiter. He is now a Postdoctoral researcher at The Open University working in atmospheric retrievals from the ACS and NOMAD instruments on the ExoMars TGO. His main interests relate to the understanding of the dust, water, and chemical cycles in the Martian atmosphere.