The ExoMars Trace Gas Orbiter (TGO) was launched in 2016 and began science operations in April 2018. NOMAD (Nadir and Occultation for MArs Discovery) is one of four instruments onboard, made up of three spectrometers built to probe the atmosphere and surface of Mars in the infrared and ultraviolet wavelengths using solar occultation, limb and nadir viewing geometries. The main objective is to characterize the composition and structure of the Martian atmosphere, including the seasonal trends of atmospheric gases, dust and clouds.  

The use of a Global Circulation Model (GCM) is a crucial part of the mission, supporting the observational planning, data retrieval and interpretation of results. This talk will outline how GCMs are used to study the atmospheric dynamics and composition of the Martian atmosphere and complement the observational data collected by TGO/NOMAD.