Kelvin wave‐induced trace constituent oscillations in the equatorial stratosphere

Kelvin wave induced oscillations in ozone (O3), water vapor (H2O), nitric acid (HNO3) and nitrogen dioxide (NO2) in the equatorial stratosphere are analyzed using Limb Infrared Monitor of the Stratosphere (LIMS) data. Power and cross‐spectrum analyses reveal coherent eastward propagating zonal wave 1 and 2 constituent fluctuations, due to the influence of Kelvin waves previously documented in the LIMS data. Comparison is made between a preliminary and the archival versions of the LIMS data (denoted V4 and V5, respectively); significant differences are found, demonstrating the sensitivity of constituent retrievals to derived temperature profiles. Because Kelvin waves have vanishing meridional velocity, analysis of tracer transport in the meridional plane is substantially simplified. Kelvin wave vertical advection is demonstrated by coherent, in‐phase temperature‐tracer oscillations, co‐located near regions of strong background vertical gradients. Regions of out‐of‐phase coherency between temperature and trace species are also observed which suggest temperature dependent photochemistry. The temperature‐ozone signatures in LIMS data are compared with a simple analytical model incorporating transport and photochemistry, and overall good agreement is found. These analyses provide a good cross‐check on the quality of satellite constituent retrievals in the tropics, and also allow simple testing of chemical model parameterization schemes.