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E. B. Kraus and E. N. Lorenz

VOL. 23, NO. 1 JOURNAL OF THE ATMOSPHERIC SCIENCES JANUARY 1966Numerical Experiments with Large-Scale Seasonal Forcing~ E. B. KRAUSWoods ~Iol~ Oceanographic Institution, Woods Hole, Mass. AND E. N. LORENZ~rassachusetts Institute of Technology, Cambridge, Mass. (Manuscript received 26 August 1965)ABSTRACT Experiments with six different heating fields in a numerical general circulation model are described

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Chester S. Gardner, Marcus S. Miller, and C. H. Liu

vertical wavelengths andvertical phase velocities were used to infer observed wave periods (T~b) which ranged from 100 to 1000 rainand horizontal wavelengths (Xx) which ranged from 70 to 2000 Ion. There may be errors, however, in theinferred values of the horizontal wavelengths because they were calculated by assuming that the observed periodequals the intrinsic period. Dominant wave activity was found at vertical wavelengths between 2-4 km and 710 km. No significant seasonal variations were evident in

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Osamu Isoguchi and Hiroshi Kawamura

were supported by strong social demands. The local circulations are quite unique in coastal zones, where sharp changes in heat, moisture, and momentum transfers, as well as in elevation, occur around the coastline. The behavior of coastal wind fields has immediate effects on social activities such as marine traffic, commercial fishing, and leisure. A lack of observational data with temporal/spatial resolution enough to research the coastal wind fields (e.g., Panel on Coastal Meteorology 1992 ) has

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J. D. Mahlman, H. Levy, and W. J. Moxim

stronglysensitive to circulation features, changing overhead sun angle and temperature. These various effectslead to some substantial interhemispheric and seasonal asymmetries in the ozone production.An analysis is performed of the transport processes leading to the pronounced poleward-downwardslope of tracer isopleths. The results demonstrate that adiabatic and diabatic effects in the eddies, as wellas diabatic effects in the zonal mean, all contribute importantly to the creation of these slopingsurfaces.As an

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Stephen I. Thomson and Geoffrey K. Vallis

). The recent work of Ghosh et al. (2017) also focuses on the impact of AMV variability but specifically on its impact on the North Atlantic European region in summer. They find a region of ocean-to-atmosphere heat flux resulting in a downstream low pressure center. Such a response is typical of the cold-air-advection response to surface heating described in Hoskins and Karoly (1981) . A similar wave train response in summer was found on seasonal time scales in the combined reanalysis and model

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F. E. Volz and R. M. Goody

. A seasonal maximum in winter months is also consistent with the sodium twilight glow. Negative results include: definite evidence against the existence of the 100-150 km haze layer invoked toaccount for some aspects of lunar eclipses; lack of correlation with meteor shower activity, speaking againstBowen's theory of rainfall anomalies; computations indicating that thermal and photochemical effects ofthe dust are probably small.1. Introduction 1.1 Dust in the upper atmosphere Dust is of

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Robert J. States and Chester S. Gardner

we employ more than 1000 h of Na wind/temperature lidar observations to characterize the mesopause region thermal structure between 80 and 105 km. These observations were made over the complete diurnal cycle throughout the year at Urbana and are used to study the seasonal variations in tidal amplitudes and phases. The tidal oscillations examined in this paper include the diurnal oscillation and its first three harmonics (waves with 12-, 8-, and 6-h periods). Extensive theoretical work has been

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Rama Shankar Yadav, Suneet Dwivedi, and Ashok Kumar Mittal

rainfall, and that the negative x – y regime corresponds to the continental ITCZ with the enhanced monsoon rainfall. Palmer (1994) introduced the forced Lorenz model as a conceptual model to explore the effects of lower boundary forcing like sea surface temperature on seasonal mean rainfall. During the summer monsoon season, the large-scale rainfall oscillates aperiodically between active spells with good rainfall and weak spells with little rainfall. Typically the transition time between active and

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Kazuyuki Miyazaki, Shingo Watanabe, Yoshio Kawatani, Yoshihiro Tomikawa, Masaaki Takahashi, and Kaoru Sato

upper boundary of the tropospheric influence extends approximately 2–3 km or 20–30 K above the tropopause ( Fischer et al. 2000 ; Hoor et al. 2004 ; Hegglin et al. 2009 ), and the seasonal CO 2 variations below 20 K above the extratropical tropopause are in phase with the tropospheric variations ( Hoor et al. 2004 ). Based on a tracer–tracer correlation analysis using satellite observations, Hegglin et al. (2009) reported that the bottom of the ExTL extends 1 km below the thermal tropopause

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John L. Stanford

intospherical harmonic functions. It is shown that a certain function of the expansion coefficients can beinterpreted as the latitudinal wavenumber (K) dependence for global stratospheric temperature variancespectra. Beyond a forcing region, the spectra can be fit to the form K'% with m= -2.7+0.5 and m= --4.14-0.6 for the upper and lower stratosphere, respectively. To within the data scatter, no seasonal dependence is found for m. The onset of the inertial subrange occurs at lower K for the upper

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