Results 321 to 330 of about 376,247 (350)

Simulation of vertical wind profile under neutral conditions

International Journal of Remote Sensing, 2007
After analysing formulations of the horizontal wind velocity above a non-uniform underlying surface, it is found that the mean height of roughness elements, fractional vegetation cover and leaf area index are the most essential parameters of vertical wind profile under neutral conditions.
T. X. Yue, W. Wang, Q. Yu, Z. L. Zhu, S. H. Zhang, R. H. Zhang, Z. P. Du   +6 more
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Solar Orbiter Neutral Solar Wind Detector

2006
Neutral hydrogen atoms, which give rise to the prominent so lar Ly-alpha corona, are closely coup led to the emerging solar-wind plasma. The density ratio of neutral hydrogen to protons is minute, ~10-6; therefore, the neutral atoms are tracers in the solar wind.
M Hilchenbach, S Orsini, KC Hsieh, E Antonucci, S Barabash, K Bamert, R Bruno, MR Collier, A Czechowski, R D'Amicis, E De Angelis, I Dandouras, AM Di Lellis, R Esser, J Giacalone, M Gruntman, SR Habbal, JR Jokipii, E Kallio, J Kota, H Kucharek, R Leoni, S Livi, I Mann, E Marsch, S Massetti, A Milillo, E Möbius, A Mura, RB Sheldon, W Schmidt, S Selci, K Szego, J Woch, P Wurz, V Zanza, TH Zurbuchen   +36 more
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Sensor Development Thermospheric Neutral Wind Measurements

2002
Abstract : This report describes progress made in the development of novel new sensors to measure the thermospheric neutral wind velocity from space. The measurements depend upon the supersonic velocity of the spacecraft to determine a velocity vector from measurement of the kinetic energy of the gas along the sensor look direction and the angle of ...
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On neutral sheets in the solar wind

Solar Physics, 1972
The structure and dynamics of neutral sheets in the solar wind is examined. The internal magnetic topology of the sheet is argued to be that of thin magnetic tongues greatly distended outward by the expansion inside the sheet. Due to finite conductivity effects, outward flow takes place across field lines but is retarded relative to the ambient solar ...
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Zonal neutral winds at equatorial and low latitudes

Journal of Atmospheric and Solar-Terrestrial Physics, 2001
Abstract Fabry–Perot interferometric (FPI) measurements of thermospheric zonal neutral winds at Arequipa, Peru ( 16.7° S , 71.5° W , −2.7° dip ), and Carmen Alto, Chile ( 23.1° S , 69.4° W , −10.2° dip ), were collected during the solar minimum periods of September–October 1996 and 1997.
C. Martinis, J. Meriwether, R. Niciejewski, M. Biondi, C. Fesen, M. Mendillo   +5 more
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Neutral Winds in the Polar Cap

1980
The optical Doppler technique of the ground-based remote sensing of the thermospheric wind is reviewed with special consideration given to the admissibility of the assumptions made in the reduction of data from a single station. Examples of observations made in the Auroral Zone indicating substantial wind gradients and vertical winds are given.
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GAS 2 instrument for neutral solar wind detectinga

Physics and Chemistry of the Earth, Part C: Solar, Terrestrial & Planetary Science, 2000
Abstract The GAS 2 instrument is designed to detect neutral atoms (especially H) of the solar wind with typical energies of about 1 keV. To separate fast atoms from intense flux of photons from the sun the coincidence technique was used. The instrument was tested and calibrated and it was shown that GAS 2 could really measure various kinds of light ...
A.P. Kalinin, M.I. Verigin, G.L. Gdalevich, A.Yu. Safronov, H. Rosenbauer, M. Banaszkiewicz, M. Hlond, T. Zarnowiecki   +7 more
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Polar wind ion bands after neutral sheet acceleration

Journal of Geophysical Research: Space Physics, 1989
The transport of polar wind protons from their ionospheric source through the magnetosphere is examined, using three‐dimensional particle codes. The trajectory simulations demonstrate the escape of the high‐latitude polar wind in the boundary layers during the quiescent magnetosphere, and, in contrast, its trapping in the nightside plasma sheet at ...
D. C. Delcourt, T. E. Moore, J. H. Waite, C. R. Chappell   +3 more
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Observation of neutral winds during an equatorial electrojet

Journal of Atmospheric and Terrestrial Physics, 1977
The vertical profile of the horizontal wind in a strong equatorial electrojet is distinctly different from profiles observed previously at other times and locations. The zonal wind speed is small and varies slowly with altitude, whereas the meridional component manifests a cross-equatorial oscillation with altitude which may result from a unique ...
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Small-scale advection and the neutral wind profile

Journal of Fluid Mechanics, 1962
The flow of air in the lowest few metres of the atmosphere is examined in the case when a neutrally stratified logarithmic profile encounters a sudden change in surface roughness. Examination of the available evidence suggests that the ratio of new to old friction velocity is given by the ratio of the roughness lengths raised to a power about equal to ...
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