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A summarization of committee findings relative to the five topic areas of severe storms, turbulence, icing, visibility and lightning is given.
Severe storms and turbulence, icing, visibility, and lightning are discussed in new programs on aircraft operations. The education of pilots and ground service personnel are reviewed. More available information of weather programs and services are examined.
Reduced visibility as a human factors problem was studied in terms of the number of lives lost and cost of aircraft accidents and incidents. Human factors in flight through turbulence in detection and avoidance techniques, pilot and crew procedures for handling workloads and distractions caused by turbulence, and aircraft handling techniques for safe flights through turbulence are investigated. Education and training were reviewed in icing problems on aircraft. Pilots failure to recognize and detect wind shear in severe storms is examined. The pilots avoidance of lightning is discussed from the human factors point of view.
Aircraft models were designed to solve aircraft lightning, severe storms, turbulence, icing, and visibility problems. Analytical modeling, wind tunnel simulation tests, ground tests, and in-flight tests were conducted.
Weather services to severe storms, turbulence, icing, visibility, and lightning are discussed. Each weather phenomenon area was explored in terms of needs, problems related to providing services, and availability of timely and appropriate information.
Data acquisition and utilization in terms of turbulence, icing visibility, lightning, and severe storms are discussed. The capability to generate the data, data collection and reduction, and data dissemination and distribution are studied.
Research results of developing experimental and prototype operational systems, sensors, and space facilities for monitoring, and understanding the atmosphere are reported. Major aspects include: (1) detection, monitoring, and prediction of severe storms; (2) improvement of global forecasting; and (3) monitoring and prediction of climate change.
The NASA Weather and Climate Program has two major thrusts. The first involves the development of experimental and prototype operational satellite systems, sensors, and space facilities for monitoring and understanding the atmosphere. The second thrust involves basic scientific investigation aimed at studying the physical and chemical processes which control weather and climate. This fourth science review concentrated on the scientific research rather than the hardware development aspect of the program. These proceedings contain 65 papers covering the three general areas: severe storms and local weather research, global weather, and climate.
Recent developments in mesometeorology are summarized to place this research in perspective. Recent advances in computer analysis and forecast system development that provide the basis for the simulation tests are discussed. The impact of NIMBUS-6 humidity data on analyses off the West Coast are shown and incorporation of geopotential gradient data is discussed. Experiments to demonstrate the feasibility of incorporating satellite-derived wind fields in mesoscale severe storm models are mentioned briefly.
Simultaneous Geosynchronous Operational Environmental Satellite (GOES) 1 km resolution visible image pairs can provide quantitative three dimensional measurements of clouds. These data have great potential for severe storms research and as a basic parameter measurement source for other areas of meteorology (e.g. climate). These stereo cloud height measurements are not subject to the errors and ambiguities caused by unknown cloud emissivity and temperature profiles that are associated with infrared techniques. This effort describes the display and measurement of stereo data using digital processing techniques.
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.
This paper briefly introduces a concept for low-cost, global, day-night, all-weather disaster warning and assistance. Evolving, advanced space technology with passive radio frequency reflectors in conjunction with an imaging synthetic aperture radar is employed to detect, identify, locate, and provide passive communication with earth users in distress. This concept evolved from a broad NASA research on new global search and rescue techniques. Appropriate airborne radar test results from this research are reviewed and related to potential disaster applications. The analysis indicates the approach has promise for disaster communications relative to floods, droughts, earthquakes, volcanic eruptions, and severe storms.
A brief overview is provided of the coherent Doppler lidar work at the Marshall Space Flight Center, taking into account the status and planned development of the system to be used for severe storms research. The considered system is a CW Doppler lidar operating at a wavelength of 10.6 micrometers. This lidar uses a 20 watt carbon dioxide laser. It has a range which is continuously variable from 60 m to approximately 600 m. Range variation is achieved through changing the focus of a 30 cm f/2 Cassegrainian telescope. Successful measurements with the CW lidar have included two and three dimensional wind profiles, wing tip vortex tracks and profiles, dust devil tracks and profiles, and transverse as well as line-of-sight wind velocities. The pulsed lidar in recent ground tests has succeeded in measuring clear air returns to a range of 13 km and has provided substantial information on velocities associated with the gust fronts of thunderstorms.
The paper examines the coupling between the ionosphere and the troposphere during time periods with isolated tornadoes on the stormy day of November 20, 1973. Observations are made with a high-frequency CW Doppler array system, in which radio receivers located at a central site monitored signals transmitted from three independent remote sites on three sets of frequencies (4.0125, 4.759, 5.734 MHz) and reflected off the ionosphere approximately halfway between the transmitter and receiver sites. It is shown that the sources of the gravity waves associated with tornadoes are always on the squall lines and near the tornado touchdown locations, and that analyses of ionospheric Doppler sounder observations of medium-scale gravity waves can contribute to the understanding of the coupling between the ionosphere and the troposphere during periods of severe storm activity.
An automatic cloud tracking system was applied to multilayer clouds associated with severe storms. The method was tested using rapid scan observations of Hurricane Eloise obtained by the GOES satellite on 22 September 1975. Cloud tracking was performed using clustering based either on visible or infrared data. The clusters were tracked using two different techniques. The data of 4 km and 8 km resolution of the automatic system yielded comparable in accuracy and coverage to those obtained by NASA analysts using the Atmospheric and Oceanographic Information Processing System.
The scientific interests and applications of the Airborne Doppler Lidar Wind Velocity Measurement System to severe storms and local weather are discussed. The main areas include convective phenomena, local circulation, atmospheric boundary layer, atmospheric dispersion, and industrial aerodynamics.
An interpretation of the Doppler lidar return is presented. Possible applications of the system to severe storm research are discussed. The present project schedule of the Doppler lidar system is outlined.
Three general areas of research were discussed: Global Weather, Upper Atmosphere, and Severe Storms and Local Weather. Research project summaries, in narrative outline form, stating objectives, significant accomplishments, and recommendations for future research are presented.