Download or read book RADAR DETECTION OF THUNDERSTORM HAZARDS FOR AIR TRAFFIC CONTROL VOL 1 STORM CELL DETECTION written by R. K. Crane and published by . This book was released on 1976 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Radar Detection of Thunderstorm Hazards for Air Traffic Control Volume I Storm Cell Detection written by Robert K. Crane and published by . This book was released on 1976 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: A procedure was developed to detect hazardous regions within thunderstorms using weather radar data. The procedure is based upon the hypothesis that convective turbulence occurs within 2-3 km of relative radar reflectivity maxima (cells). The hypothesis was tested using a limited set of simultaneous aircraft radar data. Good agreement was found between the observed regions of convective turbulence and the cell locations determined by radar. The viability of the hazard detection hypothesis as a basis for automatic warning and forecast depends upon the reliability of the cell detection and tracking algorithms. Analysis of precision radar data revealed that the cells are small in area extent, have a detection probability in excess of 0.9 using multiple radar scans, and are readily tracked for periods between 10 and 20 minutes. The characteristics of radar systems for acquiring data to support cell detection, are discussed. The role of Doppler spectral data is explored, and it is found that practical limitations on radar beamwidth hamper direct observation of turbulence on the scale size hazardous to aircraft. (Author).
Download or read book Radar Detection of Thunderstorm Hazards for Air Traffic Control Volume II Radar Systems written by S. M. Sussman and published by . This book was released on 1976 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radar systems are investigated for the acquisition of weather data to support detection and forecasting of hazardous turbulence assoicated with individual storm cells. Utilization of the FAA Airport Surveillance Radar (ASR) is explored. The issues of antenna polarization and Sensitivity Time Control (STC) that impact on shared operation for aircraft and weather detection are addressed. Candidate system configurations employing a common RF channel and dual orthogonal polarization channels are discussed. Ground clutter discrimination by coherent Doppler and noncoherent (Doppler spread) processing methods is described. An interim procedure is suggested for obtaining fixed reflectivity contour data from a Moving Target Detector for use in the all-digital ARTS. A preliminary design is presented for a new joint-use, long-range weather radar to support enroute air traffic controllers and to meet the data requirements of the National Weather Service and the Air Weather Service. (Author).
Download or read book Radar Detection of Thunderstorm Hazards for Air Traffic Control written by Lincoln Laboratory and published by . This book was released on 1976 with total page 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 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thunderstorm Turbulence Hazard Detection written by R. K. Crane and published by . This book was released on 1980 with total page 139 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report documents the development and testing of a viable aircraft hazard detection scheme which operates as well employing conventional radar data as it does employing Doppler radar data. The detection scheme was evaluated using aircraft penetrations into the most turbulent regions of hail storms. These regions are of interest when verifying that turbulence can be detected but are not optimum for evaluating the detection technique under realistic operating conditions. If, in the latter case, higher false alarm rates can be expected, more development will be necessary to utilize more effectively the available information before the hazard detection procedure can be incorporated into an air traffic control environment. The recommended program to develop the automatic hazard detection system include: refine the cell and cluster detection algorithms to reduce the effect of the statistical uncertainties in the estimation of velocity perturbations; refine the cell significance algorithms using cell age location in the development pattern, apparent vertical transport of horizontal momentum and similar parameters to provide and indication of the intensity of the turbulence; and develop a graphical display of the cell, cluster and contour data that can be provided both to meteorologists for the development of short range forecasts.
Download or read book An Evaluation of an Automatic Cell Detection and Tracking Algorithm written by James G. Wieler and published by . This book was released on 1982 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: A storm tracking algorithm designed to detect and track fine structure in digitized radar data is evaluated. These fine structures are defined by regions containing values within 3 dB of peaks in reflectivity factor. The algorithm describes storm structure and evolution by correlating these peak regions in time and space. The evaluation consists of a comparison of the algorithm output with raw data and with output from an AFGL algorithm which detects and tracks three-dimensional reflectivity weighted centroids defined by a preselected threshold. It is concluded that the algorithm cannot reliably detect and track significant structures within storms when applied to data sets with a temporal resolution of aprox. 6 min and a spatial resolution of 1.0 deg in azimuth and 0.7 deg in elevation. The significance of tracking 3 dB peaks is questioned and the implication of defining a larger peak threshold is discussed. The algorithm does track the large features of storms with results similar to the AFGL algorithm. However, it does not run in real time and is not modular, unlike the AFGL algorithm.
Download or read book Automated Cell Detection as a Mesocyclone Precursor Tool written by F. Ian Harris and published by . This book was released on 1984 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Automated cell detection in radar observations of convective storm complexes has been explored as a severe storm indicator. Six-dB peaks were detected in the radar reflectivity fields and their characteristics were monitored as a function of time. It was found in a severe tornadic storm that the number of cells and the average intensity of the cells had trends that appear to be characteristic of super-cell storms with these trends being identifiable at least 45 min before the touchdown of the first tornado and 90 min before the touchdown of a maxi tornado. None of these trends could be detected in a storm system that produced only a funnel cloud. This second storm did produce a tornado vortex signature. It would appear that the peak detection algorithm has the potential of extending the warning period for severe weather associated with super-cell and for indicating the potential of extremely severe weather. Testing has been limited and therefore these results must be considered somewhat tentative.
Download or read book US Air Transportation Industry Handbook Volume 1 Strategic Information and Important Regulations written by IBP, Inc. and published by Lulu.com. This book was released on 2018-05-18 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: 2011 Updated Reprint. Updated Annually. US Air Transportation Handbook: Regulations and Business Opportunities
Download or read book Radar Analysis for Severe Weather Detection and Tracking written by Robert K. Crane and published by . This book was released on 1982 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Radar Detection of Turbulence in Thunderstorms written by Alan R. Bohne and published by . This book was released on 1981 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theoretical investigations are undertaken to relate intensity of turbulent air motion to Doppler radar spectrum mean and variance in precipitation environments. Examples of theoretical radar derived turbulence power density spectra and total precipitation motion variance show that effects due to imperfect particle response are significant for turbulence scale lengths less than 250 m. Doppler spectrum variance and estimated eddy dissipation rate (epsilon) are found strongly dependent upon precipitation environment for ranges less than about 20 km, and for cases where the turbulence outer scale length (lambda) is less than 0.5 km. They are also found to be essentially independent of lambda when the maximum pulse volume dimension is less than 1/2 lambda, and independent of range but strongly dependent on lambda at ranges where the maximum pulse volume dimension is greater than lambda. Estimation of epsilon by radar is shown to be unreliable until a method of remotely determining lambda is found. Nevertheless, classification of turbulence severity (index = cube root of epsilon is possible with only a reasonable guess of lambda. Analyses of aircraft/gust velocity data indicate that thunderstorm turbulence is localized into discrete patches, and that such localization must be accounted for when aircraft gust velocity data undergo power spectrum analysis.
Download or read book NASA SP written by and published by . This book was released on 1992 with total page 654 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book FAR AIM written by and published by . This book was released on 2007 with total page 1052 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1985 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Annual Index written by and published by . This book was released on 1978 with total page 932 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sections 1-2. Keyword Index.--Section 3. Personal author index.--Section 4. Corporate author index.-- Section 5. Contract/grant number index, NTIS order/report number index 1-E.--Section 6. NTIS order/report number index F-Z.
Download or read book The Lincoln Laboratory Journal written by and published by . This book was released on 1994 with total page 556 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transportation Weekly Government Abstracts written by and published by . This book was released on 1991 with total page 574 pages. Available in PDF, EPUB and Kindle. Book excerpt:
