Numerical Simulation of Stratospheric Sudden Warmings with a Primitive Equation Spectral Model

Dynamical response of low-latitude middle atmosphere to major sudden stratospheric warming events

“…Due to critical level absorption, intense warming of the polar region is expected to continue below the critical level and cooling develops above the level by the adiabatic process of the zonal mean ascent. The development of westward winds is in accordance with the numerical results obtained by Lordi et al (1980). According to them, the wave-wave interactions in these simulations appear to moderate the restoring process by counteracting Rayleigh friction, which is effective in the mesosphere in restoring the intensity of zonal mean flow to its initial value.…”

“…After weakening of the westward winds, another pulse of westward winds intensified in the upper stratosphere during days 65-80 and they extended to the mesosphere and lower stratosphere, but with weaker magnitudes. Numerical simulations of stratospheric warming also suggest that westward winds first develop in the mesosphere and descend gradually, while at about the same time or later, westward winds develop in the lower stratosphere (Lordi et al, 1980). Mukhtarov et al (2007) observed that the beginning of the eastward wind deceleration in the stratosphere-mesosphere system coincided with the maximum amplification of the stationary planetary waves of zonal wave number 1 accompanied by short-lived bursts of planetary waves 2 and 3.…”

Equatorial stratospheric thermal structure and ozone variations during the sudden stratospheric warming of 2013

“…The rate of zonally averaged temperature due to the horizontal eddy heat flux convergence is given by Lordi et al (1981) …”

Large-scale thermodynamics of the stratosphere and mesosphere during the major stratospheric warming in 2003/2004

“…While the stratospheric manifestations of SSWs are reasonably well characterized from observational (Labitzke, 1965;Randel and Boville, 1987;Labitzke and Naujokat, 2000;Perlwitz and Graf, 2001) and modelling points of view (Schoeberl, 1978;Lordi et al, 1980;Hartman, 1983;Mechoso et al, 1985), the MLT manifestations are less experimentally documented and not so well understood. The initial MLT response seen in the neutral winds has been reported by Gregory and Manson (1975) and Lysenko et al (1975), while that in the temperature by Labitzke (1972) and Myrabø et al (1984).…”