Simulation of the ENSO influence on the extra-tropical middle atmosphere

The impact of the El Nio Southern Oscillation (ENSO) on the Northern Hemisphere mid-winter zonal wind, temperature, and stationary planetary waves (SPWs) is evaluated using the Middle and Upper Atmosphere Model and Modern-Era Retrospective Analysis for Research and Applications (MERRA). The composites determined using simulated ensembles and MERRA winters with different ENSO phases show that the mean zonal wind in the stratosphere at higher-middle latitudes is weaker and polar region is warmer, and the activity of SPW1 is higher during El Nio events. The simulated and observed SPW2 amplitude behaves in the opposite way, and it is stronger in the stratosphere during La Nia. The observed changes of SPW1 and SPW2 amplitudes under La Nia and El Nio events should affect an efficiency of the stratosphere-troposphere coupling in different longitudinal sectors through the changes in horizontal distributions of the downward wave activity flux.