The role of equatorial waves in the semiannual oscillation of the middle Atmosphere

摘要: A review of the observed features semiannual oscillation (SAO) middle atmosphere is presented, together with numerical simulations that reproduce much behavior. It argued latent heat release by deep convection excites equatorial Kelvin and inertia-gravity waves play a major role in driving SAO. The question have scales ranging from planetary (k = 1 - 3) to intermediate ≃ 4 25), periods less than 5 days. In calculations presented here, planetary-scale provide over half for westerly phase stratospheric SAO, while remainder supplied scale waves; mesosphere, driven combination intermediate-scale waves, diurnal period contribute most forcing easterly phase. responsible mesospheric are particularly affected dissipation during quasibiennial (QBO); this may account apparent modulation SAO QBO seen satellite observations.