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The first mesopause‐region (ca. 92±5 km) wind measurements from the meteor radar at Amundsen‐Scott Station at South Pole are described. Measurements are made along four orthogonal azimuth directions approximately 2° from the geographic South Pole. A large (±20 ms−1) oscillation in the northward wind is observed, with 12‐hour period and zonal wavenumber one. A similar wave was observed during August 1–13, 1992 at South Pole by Hernandez et al. (1993) using optical methods. The predominant semidiurnal tide in the atmosphere is migrating with the apparent motion of the sun, with s=2. The s=1 oscillation is interpreted here to result from the nonlinear interaction between the migrating semidiurnal tide and a stationary wave with s=1. The present mechanism represents an alternative to the gravity‐wave driven ‘pseudotide’ theory put forth by Walterscheid et al. (1986) to explain the occurrence of unexpectedly large semidiurnal tidal oscillations at high latitudes.

Abstract. Meteor radar measurements of winds near 95 km in four azimuth directions from the geographic South Pole are analyzed to reveal characteristics of the 12-h oscillation with zonal wavenumber one s 1. The wind measurements are con®ned to the periods from

In a unified approach, we study the transport properties of periodic-on-average bilayered photonic crystals, metamaterials, and semiconductor superlattices. Our consideration is based on the analytical expression for the localization length derived for the case of weakly fluctuating widths of layers and takes into account possible correlations in disorder. We analyze how the correlations lead to anomalous properties of transport. In particular, we show that for quarter stack layered media specific correlations can result in a omega;{2} dependence of the Lyapunov exponent in all spectral bands.

Transport characteristics of pure narrow 2D conductors, in which the electron scattering is caused by rough side boundaries, have been studied. The conductance of such strips is highly sensitive to the intercorrelation properties of inhomogeneities of the opposite edges. The case with completely correlated statistically identical boundaries (CCB) is a peculiar one. Herein the electron scattering is uniquely due to fluctuations of the asperity slope and is not related to the strip width fluctuations. Owing to this, the electron relaxation lengths, specifically the localization length, depend quite differently on the asperity parameters as compared to the conductors with arbitrarily intercorrelated edges. The method for calculating the dynamical characteristics of the CCB electron waveguides is proposed clear of the restrictions on the asperity height.

Abstract. We review recent results on the anomalous transport in onedimensional and quasi-one-dimensional systems with bulk and surface disorder. Main attention is paid to the role of long-range correlations in random potentials for the bulk scattering, and in corrugated profiles for the surface scattering. It is shown that with a proper choice of correlations one can construct such a disorder that results in a selective transport with given properties. A particular interest is in the possibility to arrange windows of a complete transparency (or reflection) in the dependence on the wave number of incoming classical waves or electrons.

Hourly wind measurements were obtained nearly continuously over these time periods, at an approximate altitude of 95 km and at about 2• latitude from South Pole along the longitude meridians 0• , 90• E, 90• W, and 180• . The scientific advances achieved to date through analyses of these data are presented, including updates to several of our previously published works. The findings addressed herein include the following: (1) Strong divergences of zonal-mean meridional winds occasionally occur over South Pole, implying extreme vertical winds; (2) The monthly mean zonally asymmetric (zonal wavenumber s = 1) wind component varies during the year in a manner consistent with migration of the center of the polar vortex with respect to the geographic (rotational) pole; (3) Strong (>15 m/s) westward-propagating migrating diurnal (s = 1) and non-migrating semidiurnal (s = 1) oscillations exist except during winter months; (4) Long-period (∼2-10 days) waves exist during winter months which are primarily eastward-propagating; (5) Intradiurnal (periods ∼6-11.5 hours) westward-propagating oscillations exist, which are thought to be gravitational normal modes, or "Lamb" waves.

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