Impact of Small-Scale Gravity Waves on Tracer Transport

The large-scale zonal-mean transport of tracers, such as ozone and water vapor, is governed by global circulations. Because of the radiative effects of tracers, an accurate representation of their transport in climate models is essential for reliable climate simulations. Small-scale processes such as gravity waves and turbulence can significantly influence the transport and distribution of tracers. As these processes are unresolved in most weather and climate models, their effects must be parameterized. We present the novel parameterization for the direct impact of gravity waves on tracer transport (Knop et al., 2026). Using multiple-scale analysis of the governing atmospheric equations, we derive expressions for gravity wave–induced tracer fluxes, enabling a physically based parameterization. The parameterization is thoroughly validated by comparing idealized simulations with parameterized waves to wave-resolving reference simulations. Finally, we aim to extend the theory to include turbulent effects.Knop, I., Dolaptchiev, S. & Achatz, U. (2026) Impact of small-scale gravity waves on tracer transport. Quarterly Journal of the Royal Meteorological Society, e70091. Available from: https://doi.org/10.1002/qj.7009