The variability, structure and energy conversion of the northern hemisphere traveling waves simulated in a Mars general circulation model

•Considerable variability is simulated with a yearly repeatable dust scenario.•Large contrast between m=1 and m=3 waves exists in wave structure and energetics.•Individual wave mode exhibits mixed baroclinic-barotropic characteristics.•Both barotropic and baroclinic conversion can be either sources or sinks of eddy kinetic energy.•Nonlinear interactions among transient eddies are weak, but non-negligible.•Wave – wave interaction appears to play a role in wave mode transition. Investigations of the variability, structure and energetics of the m=1−3 traveling waves in the northern hemisphere of Mars are conducted with the MarsWRF general circulation model. Using a simple, annually repeatable dust scenario, the model reproduces many general characteristics of the observed traveling waves. The simulated m=1 and m=3 traveling waves show large differences in terms of their structures and energetics. For each representative wave mode, the geopotential signature maximizes at a higher altitude than the temperature signature, and the wave energetics suggests a mixed baroclinic-barotropic nature. There is a large contrast in wave energetics between the near-surface and higher altitudes, as well as between the lower latitudes and higher latitudes at high altitudes. Both barotropic and baroclinic conversions can act as either sources or sinks of eddy kinetic energy. Band-pass filtered transient eddies exhibit strong zonal variations in eddy kinetic energy and various energy transfer terms. Transient eddies are mainly interacting with the time mean flow. However, there appear to be non-negligible wave-wave interactions associated with wave mode transitions. These interactions include those between traveling waves and thermal tides and those among traveling waves.