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Third Chapman-Enskog approximation to tensor electrical conductivity of partially ionized gas applied to two conductivity mixture rules for atmospheric cesium seeded argon
Simultaneous measurements have been made of the ionospheric electric field at altitudes above 100 km (with rockets and radar) and of the atmospheric electric field at an altitude of about 30 km (with balloons). These results show that the horizontal components of the electric field at 30 km were essentially equal to the ionospheric electric field, as has been argued previously on theoretical grounds.
Abstract The dissonant development of positive and negative lightning leaders is a central question in atmospheric electricity. It is also the likely root cause of other reported asymmetries between positive and negative lightning flashes, including the ones regarding: stroke multiplicity, recoil activity, leader velocities, and emission of energetic radiation. In an effort to contrast lightning leaders of different polarities, we highlight the staggering differences between two rocket‐triggered lightning flashes. The flash beginning with upward positive leaders exhibits an initial continuous current stage followed by multiple sequences of dart leaders and return strokes. On the other, in its opposite‐polarity counterpart, the upward development of negative leaders is by itself the entire flash. As a result, the flash with negative leaders is faster, briefer, transfers less charge to the ground, has lower currents, and smaller spatial extent. We conclude by presenting a discussion on the three fundamental leader propagation modes.
Ball lightning formation attributed to low hydrocarbon density coupled with atmospheric electrical discharge
The effects of extreme values of surface and low altitude atmospheric parameters on space vehicle design, tests, and operations are discussed. Atmospheric extremes from the surface to 150 meters for geographic locations of interest to NASA are given. Thermal parameters (temperature and solar radiation), humidity, pressure, and atmospheric electricity (lighting and static) are presented. Weather charts and tables are included.
The photoemission of materials which might be used in probe measurements of the exo-atmospheric electric field is considered by evaluating the wavelength dependence of their photoelectric yield for eleven elements over the range 800 to 3200 A. Yield data for zinc, copper beryllium, platinum, cadmium, graphite, carbon, gold, silver, tantalum, and tungsten show that copper-beryllium is a preferred material. Silver has one of the highest photoemissions when exposed to solar radiation.
Probable climatic extremes of terrestrial environment data specifically applicable for NASA space vehicles and associated equipment development are considered. Design guideline values are established for the following environmental parameters: (1) Thermal (temperature and solar radiation); (2) humidity; (3) precipitation; (4) winds; (5) pressure; (6) density; (7) electricity (atmospheric); (8) corrosion (atmospheric); (9) sand and dust; (10) fungi and bacteria; (11) atmospheric oxidants; (12) composition of the atmosphere; and (13) inflight thermodynamic properties.
Criteria are provided on atmospheric extremes from the surface to 150 meters for geographical locations of interest to NASA. Thermal parameters (temperature and solar radiation), humidity, precipitation, pressure, and atmospheric electricity (lightning and static) are presented. Available data are also provided for the entire continental United States for use in future space programs.
The nature of the wave interactions, particularly those induced by transient solar and geomagnetic phenomena is discussed. Solar activity which includes modulations of galactic cosmic ray flux reaching Earth is discussed. Coupling processes involving charged particles and atmospheric electric structure are presented.
The results of the Workshop on the Need for Lightning Observations from Space held February 13-15, 1979, at the University of Tennessee Space Institute, Tullahoma, Tennessee are presented. The interest and active involvement by the engineering, operational, and scientific participants in the workshop demonstrated that lightning observations from space is a goal well worth pursuing. The unique contributions, measurement requirements, and supportive research investigations were defined for a number of important applications. Lightning has a significant role in atmospheric processes and needs to be systematically investigated. Satellite instrumentation specifically designed for indicating the characteristics of lightning are of value in severe storms research, in engineering and operational problem areas, and in providing information on atmospheric electricity and its role in meteorological processes.
Significant acomplishments, current focus of work, plans for FY-80, and recommendations for new research are outlined for 36 research projects proposed for technical monitoring by the Atmospheric Sciences Division at Marshall Space Flight Center. Topics of the investigations, which were reviewed at a two-day meeting, relate to cloud physics, atmospheric electricity, and mesoscale/storm dynamics.
Several related investigations of the possible influence of the solar and interplanetary magnetic sector structure on the atmospheric circulation are described. The area of low pressure troughs in the northern hemisphere has a minimum about one day after a warped heliospheric current sheet has been carried past the earth by the solar wind. Possible physical mechanisms could relate to phase changes in meteorological processes, changes in atmospheric electricity or changes in solar extreme ultraviolet irradiation. A quantitative analysis suggests that the accuracy of weather forcasting decreases during the two days after the warped heliospheric current sheet has passed the earth. A description is given of several further investigations in progress.
The proceedings of a workshop on meteorological and environmental inputs to aviation systems are reported. The major objectives of the workshop are to satisfy such needs of the sponsoring agencies as the expansion of our understanding and knowledge of the interaction of the atmosphere with aviation systems, the better definition and implementation of services to operators, and the collection and interpretation of data for establishing operational criteria, relating the total meteorological inputs from the atmospheric sciences to the needs of aviation communities. The unique aspect of the workshop was the achievement of communication across the interface of the boundaries between pilots, meteorologists, training personnel, accident investigators, traffic controllers, flight operation personnel from military, civil, general aviation, and commercial interests alike. Representatives were in attendance from government, airlines, private agencies, aircraft manufacturers, Department of Defense, industries, research institutes, and universities. Full-length papers addressed the topics of training, flight operations, accident investigation, air traffic control, and airports. Winds and wind shear; icing and frost; atmospheric electricity and lightning; fog, visibility and ceilings; and turbulence were discussed.
The proceedings of a workshop on meteorological and environmental inputs to aviation systems held at The University of Tennessee Space Institute, Tullahoma, Tennessee, March 25-27, 1980, are reported. The workshop was jointly sponsored by NASA, NOAA, and FAA and brought together many disciplines of the aviation communities in round table discussions. The major objectives of the workshop are to satisfy such needs of the sponsoring agencies as the expansion of our understanding and knowledge of the interaction of the atmosphere with aviation systems, the better definition and implementation of services to operators, and the collection and interpretation of data for establishing operational criteria relating the total meteorological inputs from the atmospheric sciences to the needs of aviation communities. The unique aspects of the workshop were the diversity of the participants and the achievement of communication across the interface of the boundaries between pilots, meteorologists, training personnel, accident investigators, traffic controllers, flight operation personnel from military, civil, general aviation, and commercial interests alike. Representatives were in attendance from government, airlines, private agencies, aircraft manufacturers, Department of Defense, industries, research institutes, and universities. Full-length papers from invited speakers addressed topics on icing, turbulence, wind and wind shear, ceilings and visibility, lightning, and atmospheric electricity. These papers are contained in the proceedings together with the committee chairmen's reports on the results and conclusions of their efforts on similar subjects.
The dynamic and rapid growth of technology in the area of aviation meteorology research and development are described with emphasis on the measurement of hazardous weather phenomena. Aspects of both onboard instrumentation and ground based facilities are evaluated in terms of their effectiveness of in avoiding hazards due to atmospheric electricity and lightning. Methods of alleviating terminal are hazards such as fog, low visibility and ceilings are also described.
The atmospheric electricity and lightning committee forecasts lightning and dissemination of information on the probability of occurrence. A data source with the F-106 flight program was established. The objective is to improve the detectability of lightning and severe storms and help develop operational avoidance procedures and to study the use of satellite and Doppler radar to detect thunderstorms and forecast the probability of lightning. Three recommendations are made: (1) to establish a national flying lightning laboratory; (2) strike models are considered and to gather strike data; (3) to find the best way to apply electrical field data to operations.
Current and ongoing research programs related to various areas of aviation meteorology are presented. Literature searches of major abstract publications, were conducted. Research project managers of various government agencies involved in aviation meteorology research provided a list of current research project titles and managers, supporting organizations, performing organizations, the principal investigators, and the objectives. These are tabulated under the headings of advanced meteorological instruments, forecasting, icing, lightning and atmospheric electricity; fog, visibility, and ceilings; low level wind shear, storm hazards/severe storms, turbulence, winds, and ozone and other meteorological parameters. This information was reviewed and assembled into a bibliography providing a current readily useable source of information in the area of aviation meteorology.
The Workshop was held at the National Center for Atmospheric Research (NCAR) in Boulder, Colorado, on February 1-2, 1983. The Workshop was attended by seventeen experts in the scientific fields of fog and cloud physics, charged-particle electrodynamics, atmospheric turbulence, atmospheric electricity, and electro-gasdynamics. The major objective of the Workshop was to assess the scientific merits and scientific basis of the proposed system and to assess its potential for operational application.