Showing papers in "Journal of Atmospheric and Solar-Terrestrial Physics in 1986"

TL;DR: In this paper, the SOUSY radar in West Germany has been used to measure absolute values of effective reflection coefficients and turbulence structure constants as a function of altitude, and the profiles are presented for both a vertically directed beam and also for two beams directed 7° off-vertical.

TL;DR: In this article, the zonal mean wind momentum budget (80-90 km) is assessed using cross-sections of northward-eastward covariances for wind fluctuations in the planetary and tidal wave period ranges and also gravity wave crosssections.

TL;DR: In this article, the authors observed medium-scale travelling ionospheric disturbances (MSTIDs) at Leicester, U.K. (52°32′N 1°8′W) by means of the HF Doppler technique.

TL;DR: GEN-SYSTEM as mentioned in this paper is a code name for a new experimental design philosophy, a set of related correlator algorithms and an experiment library based on this philosophy, designed to obtain an easy way to develop powerful experiments having several different modulations in the same pattern.

TL;DR: In this article, the intensity of atmospheric turbulence in the middle atmosphere has been investigated by utilizing the spectral halfwidths of echoes received by a VHF radar in West Germany and this is the first time that the technique has been tested in such detail at VHF.

TL;DR: In this paper, the authors deduced the time constants for Hall conductivity changes in the auroral D -region caused by HF heating from the VLF/ELF signals recorded on the ground underneath the heated region.

TL;DR: In this article, an improved model for non-equilibrium radiative transfer processes in the middle atmosphere (40-120 km) is presented, which is compared to previously published results for the 15 μm bands of carbon dioxide and the relative importance of various energy transfer mechanisms at work, including those involving overtone bands and isotopic species and pumping by sunlight during the day.

TL;DR: A non-equilibrium radiative transfer model has been applied to the 2.7 and isotopic 4.3 μm bands of CO 2, together with that of H 2 O at 6.3 µm and the first excited vibrational levels of the nitrogen and oxygen molecules.

TL;DR: In this paper, the dynamo current induced by the two-day wave is examined and the resulting geomagnetic variation at ground-level is estimated; two types of wind models are used in the calculation; they are symmetric and antisymmetric atmospheric normal modes.

TL;DR: In this article, the apparent position shift of a radio source observed with a two-dimensional radio interferometer provides directly the two components of the horizontal gradient of the oblique electronic content along the line of sight.

TL;DR: In this paper, the upward flux of horizontal momentum, and hence the mean flow acceleration associated with these waves, is now accessible, as are better estimates of horizontal scales and phase velocities.

TL;DR: Magnetic storm effects on the F2-layer at Ibadan (lat. 7.4°N, long. 3.9°E, magnetic dip 6°S) were observed over a solar cycle period (1956-1966).

TL;DR: In this paper, the continuity equation for the ionospheric F2-layer was discussed and principles which help to establish what processes could be effective in causing storm effects or other F2layer phenomena.

TL;DR: In this paper, measurements of ion temperature, ion-neutral collision frequency and ion drift in the E -region from the period December 1984 to November 1985 were used to derive neutral temperatures, densities and meridional winds in the altitude intervals 92-120 km, 92-105 km and 92 -120 km.

TL;DR: In this paper, the authors used data from the Advanced Ionospheric Sounder (AIS) deployed at Halley, Antarctica (76-deg S, 27-deg W; L = 4.2) and the Dynamics Explorer-2 spacecraft (DE-2) to investigate several aspects of the formation processes and dynamics of the poleward edge of the midlatitude electron density trough.

TL;DR: In this article, the EISCAT UHF system reveals substantial nonisotropic ion temperatures in the auroral F-region, and the increase in the ion temperature parallel to the magnetic field is associated with Joule heating events.

TL;DR: In this article, the effects of Doppler shifts on gravity wave spectra observed by MST radar are investigated and general expressions for radar observed spectra are derived, and the results are applied to interpret some observational data.

TL;DR: In this paper, the growth rate and ion-electron recombination rate for the Rayleigh-Taylor instability on the F-region bottomside is examined as a function of the vertical eastward electric field-magnetic field strength drift velocity.

TL;DR: The EISCAT incoherent scatter facility consists of two systems, one operating at 933 MHz (UHF) and one at 224 MHz (VHF) as discussed by the authors, and the UHF tristatic facility has been in full operation for over two years.

TL;DR: In this article, the effects of regional gravity wave sources, together with temporal changes of gravity wave activity, are studied under solstice conditions in a 3D circulation model using a simplified parameterization scheme for the gravity momentum deposition.

TL;DR: In this paper, the authors used EISCAT data for a systematic study of the high latitude trough and found that the pattern was the same in all cases, apart from a few days at midwinter.

TL;DR: In this article, a comparison of calculated and observed monthly mean day-time ionospheric F 2-peak density (NmF 2) at a chain of stations from Japan to Australia for both solar minimum (1976) and solar maximum (1980).

TL;DR: In this paper, high-resolution measurements of Doppler shift and broadening of the (OI) >1630 nm emission in the night airglow and aurora have provided determinations of vertical velocities and temperatures in the neutral thermosphere over Mawson, Antarctica.

TL;DR: In this article, ground-based microwave observations of the 142.175 GHz ozone line were made to measure the variations of mesospheric ozone during sunset, throughout the night and during sunrise.

TL;DR: In this paper, three nights near midsummer were studied and in each case a trough in electron density occurred north of invariant latitude 64° shortly after local midnight (MLT 0200) and remained a prominent feature for about 3 h before moving poleward.

TL;DR: In this paper, the altitude-latitude distributions of cooling rate in the 15 μm CO 2 and 9.6 μm O 3 bands and in the rotational H 2 O band have been calculated.

TL;DR: In this article, the authors show that large-scale irregularities of ionization density in the F -region of the ionosphere can explain the frequency spread on F-region ionograms, but this mechanism alone does not produce enough frequency spread to explain satisfactorily the more extensive forms of spread.

TL;DR: In this article, a multichannel Barker coded EISCAT experiment with basic spatial and temporal resolutions of 600 m and 10 s, respectively, is described, and the experiment was run on 13-17 February 1984 and data obtained in a diffuse aurora as well as in an auroral arc are used for determining the ion-neutral collision frequency in the lower E -region.

TL;DR: In this paper, the authors used in situ rocket techniques under night-time conditions at Wallops Island, Virginia, on 23 August 1984, to study the effect of lightning on the magnetosphere.

TL;DR: In this article, the accuracy of electron densities in routinely analyzed EISCAT data is discussed and comparisons are made between the EISCat measurements and those determined by rockets and an ionosonde.