Download or read book Lower Thermosphere Density Variations in the Southern Hemisphere written by F. A. Marcos and published by . This book was released on 1972 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: Profiles of the neutral atmospheric density have been obtained at high and middle latitudes in the southern hemisphere from OV1-15 (SPACES) satellite accelerometer measurements. The data were obtained during a geomagnetically quiet period near the equinox, 24-28 September 1968, when the satellite was in a nearly down-dusk orbit. Perigee moved from 50 degrees S to 65 degrees S during this period. Measurements were made in the altitude range 170-250 km. Density values at dusk at high latitudes (before perigee) are less than those at midlatitudes (after perigee). The average difference between the high latitude and midlatitude data is 15 percent. A longitudinal variation is superimposed on the latitudinal gradients. Enhanced densities at high southern latitudes are found at longitudes near the south geomagnetic pole. (Author).

Download or read book Lower thermosphere Neutral Density Profiles Derived from Satellite Accelerometer Data written by F. A. Marcos and published by . This book was released on 1976 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Cannon Ball II and SPADES satellites carried triaxial accelerometer systems for accurate measurement of neutral atmospheric density. Cannon Ball II was launched 6 August 1971 into a polar elliptic orbit in which the initial perigee was at the extremely low altitude of 132 km. SPADES was launched 11 July 1968 into a polar elliptic orbit in which the initial perigee was at 155 km. The data, analyzed to deduce an average density profile for each satellite for summer conditions in the northern hemisphere, are for the altitude region 135 to 250 km, where measurements have heretofore been extremely sparse. Comparisons were made with recent models and experimental data. These results are intended to be supplemented by those of lower-thermosphere studies now being carried out on accelerometer data from the Atmosphere Explorer satellites and a low-altitude Air Force satellite. Comprehensive analyses of accelerometer data low-altitude satellites will allow accurate modeling of the lower thermosphere. These models are required for improving calculation of the trajectories of Air Force systems vehicles and other spacecraft.

Download or read book Dynamics and Structure of the Quiet Thermosphere written by K. S. W. Champion and published by . This book was released on 1974 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The COSPAR International Reference Atmospheres (CIRA) 1972 provides both a Mean International Reference Atmosphere of the thermosphere and a parametric set of models for the region. The models are based on knowledge of the thermosphere as of mid 1971. The differences in the diurnal variations of atmospheric density scale height obtained from satellite drag studies and temperatures obtained from incoherent radar scatter observations are probably due to different diurnal variations of density and temperature and not due to systematic discrepancies in the measurements. The answer to this question should be provided by data obtained from recently launched satellites ESRO IV, AEROS, and AE-C. The second major area of interest involves the absolute number densities and variations with time of day, latitude, and season of the major and minor constituents of the thermosphere. Recent data obtained with mass spectrometers and optical instruments are reviewed in addition to the results of theoretical composition calculations, which include turbulence and other transport effects.

Download or read book A Global Thermospheric Density Model Based on Satellite Accelerometer Data written by Frank A. Marcos and published by . This book was released on 1982 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements from the accelerometer experiments on four low-altitude satellites (S3-1 and Atmosphere Explorer-C, -D, and -E) have been combined to produce an empirical model of the neutral mass density from 140 to 240 km. Data from over a 8000 orbits are analyzed using the least-squares method of multiple linear regression. The resulting model gives density as a function of solar flux (for flux values 60 to 130 units), geomagnetic activity, day of year, local time, latitude and altitude. It provides a more accurate fit to the measured data than other available atmospheric models. Three commonly used models are evaluated by comparison of their predicted density variations with those of this empirical model.

Download or read book Species Densities in the Lower Thermosphere Compatible with the U S Standard Atmosphere written by Gene W. Adams and published by . This book was released on 1970 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Density Variations in the Lower Thermosphere written by William F. Johnson and published by . This book was released on 1974 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Variations with Season and Latitude of Density Temperature and Composition in the Lower Thermosphere written by K. S. W. Champion and published by . This book was released on 1967 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Analysis of neutral density data has made it possible to extend curves of mean density as a function of latitude and season from 90 to 120 km. There is an approximate isopycnic point at 91 km. Above this point the density variations are reversed from what they are at 80 km. In other words, at 120 km the density in summer and at the tropics is lower than that in CIRA 1965 and in winter the density is higher. The density curves have been idealized near 120 km to join at one of three points. These correspond to typical summer and tropical conditions, winter conditions, and spring/autumn conditions. The summer density is 20 percent below that of the U.S. Standard, the winter density is 50 percent above the Standard and the spring/autumn density is 1 percent above the Standard. By application of appropriate theory the corresponding variations in temperature and mean molecular weight have been calculated. An unexpected result of the theory is the prediction of a seasonal variation of the mean molecular weight. Some of the data presented in the paper have been analyzed since the models were derived. These data have been found to be acceptably close to the models. (Author).

Download or read book Middle Atmosphere written by PLUMB and published by Birkhäuser. This book was released on 2013-11-21 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: PAGEOPH, stratosphere, these differences provide us with new evidence, interpretation of which can materially help to advance our understanding of stratospheric dynamics in general. It is now weil established that smaller-scale motions-in particular gravity waves and turbulence-are of fundamental importance in the general circulation of the mesosphere; they seem to be similarly, if less spectacularly, significant in the troposphere, and probably also in the stratosphere. Our understanding of these motions, their effects on the mean circulation and their mutual interactions is progressing rapidly, as is weil illustrated by the papers in this issue; there are reports of observational studies, especially with new instruments such as the Japanese MV radar, reviews of the state of theory, a laboratory study and an analysis of gravity waves and their effects in the high resolution "SKYHI" general circulation model. There are good reasons to suspect that gravity waves may be of crucial significance in making the stratospheric circulation the way it is (modeling experience being one suggestive piece of evidence for this). Direct observational proof has thus far been prevented by the difficulty of making observations of such scales of motion in this region; in one study reported here, falling sphere observations are used to obtain information on the structure and intensity of waves in the upper stratosphere.

Download or read book Modeling the Ionosphere Thermosphere written by J. D. Huba and published by John Wiley & Sons. This book was released on 2014-03-17 with total page 735 pages. Available in PDF, EPUB and Kindle. Book excerpt: Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 201. Modeling the Ionosphere-Thermosphere System brings together for the first time a detailed description of the physics of the IT system in conjunction with numerical techniques to solve the complex system of equations that describe the system, as well as issues of current interest. Volume highlights include discussions of: Physics of the ionosphere and thermosphere IT system, and the numerical methods to solve the basic equations of the IT system The physics and numerical methods to determine the global electrodynamics of the IT system The response of the IT system to forcings from below (i.e., the lower atmosphere) and from above (i.e., the magnetosphere) The physics and numerical methods to model ionospheric irregularities Data assimilation techniques, comparison of model results to data, climate variability studies, and applications to space weather Providing a clear description of the physics of this system in several tutorial-like articles, Modeling the Ionosphere-Thermosphere System is of value to the upper atmosphere science community in general. Chapters describing details of the numerical methods used to solve the equations that describe the IT system make the volume useful to both active researchers in the field and students.

Download or read book Density Variations in the Thermosphere and Lower Exosphere During Geomagnetic Disturbances written by Max Roemer and published by . This book was released on 1976 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Models of Earth s Atmosphere 90 to 2500 Km written by George Y. Lou and published by . This book was released on 1973 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Air Force Surveys in Geophysics written by and published by . This book was released on 1974 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1991 with total page 910 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Understanding the Causes of Asymmetries in Earth s Magnetosphere Ionosphere System written by Denny Oliveira and published by Frontiers Media SA. This book was released on 2023-04-25 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Atmosphere and Climate of Mars written by Robert M. Haberle and published by Cambridge University Press. This book was released on 2017-06-29 with total page 613 pages. Available in PDF, EPUB and Kindle. Book excerpt: Humanity has long been fascinated by the planet Mars. Was its climate ever conducive to life? What is the atmosphere like today and why did it change so dramatically over time? Eleven spacecraft have successfully flown to Mars since the Viking mission of the 1970s and early 1980s. These orbiters, landers and rovers have generated vast amounts of data that now span a Martian decade (roughly eighteen years). This new volume brings together the many new ideas about the atmosphere and climate system that have emerged, including the complex interplay of the volatile and dust cycles, the atmosphere-surface interactions that connect them over time, and the diversity of the planet's environment and its complex history. Including tutorials and explanations of complicated ideas, students, researchers and non-specialists alike are able to use this resource to gain a thorough and up-to-date understanding of this most Earth-like of planetary neighbours.

Download or read book Report on Research at AFCRL written by Air Force Cambridge Research Laboratories (U.S.) and published by . This book was released on 1974 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Observations of Noctilucent Clouds written by and published by . This book was released on 1969 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: