Aura/MLS observes and SD-WACCM-X simulates the seasonality, quasi-biennial oscillation and El Niño–Southern Oscillation of the migrating diurnal tide driving upper mesospheric CO primarily through vertical advection

This work then compares these observations to simulations by the specified dynamics - whole atmosphere community climate model with ionosphere/thermosphere extension (SD-WACCM-X).

Results show that, for all seasons, MLS CO local-time perturbations peaks above 85 km and has a latitude structure resembling the (1,1) mode in temperature. On the other hand, SD-WACCM-X DW1 also peaks above 85 km and has a latitude structure resembling the (1,1) mode, but it simulates two local maximum of the (1,1) mode between 85 and 92 km. Despite the differences in altitude structure, a tendency analysis and the adiabatic displacement method revealed that, on seasonal and interannual timescales, observed and modeled CO's (1,1) component can be reproduced solely using vertical advection.