Download or read book Detection of Gust Fronts Using Surface Sensors written by A. J. Bedard and published by . This book was released on 1977 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Thunderstorm Gust Front Detection System Part I System Operation and Significant Case Studies Part II Statistical Results written by and published by . This book was released on 1979 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Dulles International Airport wind and wind shear detection system recorded more than 160 events from November 1976 through March 1978. Eighty-two percent of 113 significant events occurred in conjunction with thunderstorms, squall-lines and frontal passages. The chief source of false alarms for anemometers was boundary layer disturbances representing 10% of the total; while gravity shear waves related to the 500mb winds caused the most false alarms for pressure sensors (4% of the total). Using complementary arrays of wind and pressure sensors, total system false alarms can be greatly reduced. These data demonstrate the importance of stable surface layers in determining how well surface temperature and wind measurements represent flow at higher levels and explain underestimates of system severity. Moreover, because we demonstrate the value of wind vector information and since temperature is a scaler quantity, there seems little operational value in using temperature sensors as part of a detection system. Conversely, pressure sensors will not reliably detect relatively thin outflows (100-200 M thick) occurring at a distance from downflows having small dimensions. Again, the wind and pressure sensors combine to provide a total system offering good reliability for detection of thunderstorm outflows. The results suggest an array configuration (composed of wind and pressure jump sensors) for use in airport warning systems. This configuration extending about 10km from the airport provides a warning for Thunderstorm gust-fronts.

Download or read book Atmospheric Pressure Jumps Measured with Arrays of Sensitive Pressure Sensors in the Vicinity of Chicago s O Hare International Airport written by A. J. Bedard and published by . This book was released on 1977 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book On the Potential Use of the Terminal Doppler Weather Radar Gust Front Detection Algorithm on the WSR 88D System written by Gregory J. Stumpf and published by . This book was released on 1991 with total page 46 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 1977 with total page 1006 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Detection of Gust Fronts Using the Doppler Velocity Derived Divergence Product written by Russell J. Clemins and published by . This book was released on 2018 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: Identifying gust fronts can be essential for situational awareness when developing nowcasts during convective events. In addition to bearing potentially damaging winds, gust fronts also act as forcing mechanisms; influencing storm initiation, development, and propagation. Using doppler radar, gust fronts are usually observed by the presence of a reflectivity thin line ahead of the parent storm. In the situation where a thin line is not visible on radar, there is a loss of situational awareness. This study aimed to determine if gust fronts can be observed through the doppler velocity derived divergence product by isolating contiguous areas of divergence (convergence) that form couplets or line features, relative to the leading edge or ahead of a storm. Radar data for the study was collected using the University of Missouri -- Columbia's MZZU X-Band radar, as well as the WSR-88D from the NWS Saint Louis CFO. Data processing was performed through the Warning Decision Support System Integrated Information (WDSS-II), and the data was analyzed using the MatLab software. Thresholds for minimum pixel area, as well as minimum and maximum divergence (convergence) were used to establish a range of interest. Data was then filtered through a process of dilation and erosion, to prune out noise and highlight larger features. Through multiple cases using MZZU and KLSX, suitable criteria were developed that allowed the identification of Div-Conv couplets and linear regions of convergence that suggest the presence of gust fronts. Eddy covariance towers near Columbia, MO were used for surface observations of vertical velocity (w) and Turbulence Kinetic Energy (TKE). Good agreement was found between increases in w and TKE when gust fronts were detected and propagating through the region.

Download or read book Federal Register written by and published by . This book was released on 1979-05 with total page 1344 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Monthly Catalog of United States Government Publications written by United States. Superintendent of Documents and published by . This book was released on 1978 with total page 1228 pages. Available in PDF, EPUB and Kindle. Book excerpt: February issue includes Appendix entitled Directory of United States Government periodicals and subscription publications; September issue includes List of depository libraries; June and December issues include semiannual index

Download or read book Federal Information Processing Standards Publication written by and published by . This book was released on with total page 1228 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development and Testing of the Gust Front Algorithm written by Arthur Witt and published by . This book was released on 1987 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: Threshold changes, additions, and other refinements to the original version of the Gust Front Algorithm are documented. Threshold changes include a minimum velocity difference threshold, the maximum azimuthal separation between vectors, and maximum range separation. Additions include gust front tracking and forecasting in Cartesian coordinates, vertical continuity checks of gust front features to reduce the occurrence of false detections, and horizontal wind estimation both ahead and behind a detected gust front using single Doppler velocity data. Results of these additions and the effects of threshold changes on detection capability are presented for several case studies. Keywords: Wind shear; Doppler radar; Gust fronts.

Download or read book Aviation Weather Surveillance Systems written by Pravas Mahapatra and published by IET. This book was released on 1999 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: Focusing on radar-based surveillance, this book has been written to provide a comprehensive introduction to the science, sensors and systems that form modern aviation weather surveillance systems.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1986 with total page 1056 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Wind Shear written by and published by . This book was released on 1987 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Applications of Ground based Remote Sensing Techniques written by Donald R. Fitzgerald and published by . This book was released on 1980 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of selected techniques for the remote measurement of winds, shear, turbulence, aerosols, and temperature and moisture profiles has been outlined in some detail. Emphasis has been placed on techniques that may provide high-resolution data in the vicinity of airbases. A representative and fairly extensive list of references to the evolution of the various techniques has been prepared. The FM-CW radar and CO2 pulse Doppler laser have been identified as valuable for low-level wind and shear measurements. Strong downdraft conditions may be identified through use of infrared thermal anomaly detectors. Temperature and moisture profiles may be obtained through a combination of active sounding for profile inflection points and thermal or microwave multichannel radiometry.

Download or read book Terminal Doppler Weather Radar TDWR Site Determination Program written by and published by . This book was released on 1991 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Airborne Wind Shear Detection and Warning Systems Fourth Combined Manufacturers and Technologists Conference Part 1 written by and published by . This book was released on 1992 with total page 730 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Low Altitude Wind Shear and Its Hazard to Aviation written by National Research Council and published by National Academies Press. This book was released on 1983-02-01 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: