scholarly journals Of Fire and Smoke Plumes, Polarimetric Characteristics

2020 ◽  
Author(s):  
Dusan Zrnic ◽  
Pengfei Zhang ◽  
Valery Melnikov ◽  
Djordje Mirkovic
Keyword(s):  
Urban Area ◽  
Forest Fire ◽  
Computational Electromagnetics ◽  
Weather Radar ◽  
Doppler Weather Radar ◽  
National Weather Service ◽  
Weather Radars ◽  
Wild Fire ◽  
Smoke Plumes ◽  
The Usa

Weather surveillance radars routinely detect smoke of various origin. Of particular significance to the meteorological community are wildfires in forests and/or prairies. For example, one responsibility of the National Weather Service in the USA is to forecast fire outlooks as well as to monitor wild fire evolution. Polarimetric variables have enabled relatively easy recognitions of smoke plumes in data fields of weather radars. Presented here are the fields of these variables from smoke plumes caused by grass fire, brush fire, and forest fire. Histograms of polarimetric data from plumes contrast these three cases. Most of the data are from the polarimetric Weather Surveillance Radar 1988 Doppler (WSR-88D aka Nexrad, 10 cm wavelength) hence the wavelength does not influence these comparisons. Nevertheless, in one case simultaneous observations of a plume by the operational Terminal Doppler Weather Radar (TDWR, 5 cm wavelength) and a WSR-88D is used to infer backscattering characteristic and hence sizes of dominant contributors to the returns. In addition, comparisons with observations by other investigators of plumes from urban area but at a 5 cm wavelength are made. To interpret some measurements Computational Electromagnetics (CEM) tools are applied.

scholarly journals Of Fire and Smoke Plumes, Polarimetric Radar Characteristics

Atmosphere ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 363
Author(s):  
Dusan Zrnic ◽  
Pengfei Zhang ◽  
Valery Melnikov ◽  
Djordje Mirkovic
Keyword(s):  
Forest Fire ◽  
Satellite Images ◽  
Cold Front ◽  
Computational Electromagnetics ◽  
Weather Radar ◽  
Doppler Weather Radar ◽  
Polarimetric Radar ◽  
Weather Radars ◽  
Smoke Plumes ◽  
The Usa

Weather surveillance radars routinely detect smoke of various origin. Of particular significance to the meteorological community are wildfires in forests and/or prairies. For example, one responsibility of the National Weather Service in the USA is to forecast fire outlooks as well as to monitor wildfire evolution. Polarimetric variables have enabled relatively easy recognitions of smoke plumes in data fields of weather radars. Presented here are the fields of these variables from smoke plumes caused by grass fire, brush fire, and forest fire. Histograms of polarimetric data from plumes contrast these cases. Most of the data are from the polarimetric Weather Surveillance Radar 1988 Doppler (WSR-88D aka NEXRAD, 10 cm wavelength); hence, the wavelength does not influence these comparisons. Nevertheless, in one case, simultaneous observations of a plume by the operational Terminal Doppler Weather Radar (TDWR, 5 cm wavelength) and a WSR-88D is used to infer backscattering characteristic and, hence, sizes of dominant contributors to the returns. To interpret these measurements, Computational Electromagnetics (CEM) tools are applied. For one wildfire from Oklahoma, radar and satellite (GOES-16, Geostationary Operational Environmental Satellite) images are analyzed. The case demonstrates a potential to forecast fire intensification caused by a very rapid cold front. Finally, we suggest a possible way to extract the smoke plume return from the class of nonmeteorological scatterers.

scholarly journals Multi-PRI Signal Processing for the Terminal Doppler Weather Radar. Part I: Clutter Filtering

2005 ◽  
Vol 22 (5) ◽  
pp. 575-582 ◽  
Author(s):  
John Y. N. Cho ◽  
Edward S. Chornoboy
Keyword(s):  
Finite Impulse Response ◽  
Signal Transmission ◽  
Weather Radar ◽  
Spectral Width ◽  
Doppler Weather Radar ◽  
Strong Suppression ◽  
Weather Radars ◽  
Ground Clutter ◽  
Anomalous Propagation ◽  
Repetition Interval

Abstract Multiple pulse repetition interval (multi-PRI) transmission is part of an adaptive signal transmission and processing algorithm being developed to aggressively combat range–velocity ambiguity in weather radars. In the past, operational use of multi-PRI pulse trains has been hampered due to the difficulty in clutter filtering. This paper presents finite impulse response clutter filter designs for multi-PRI signals with excellent magnitude and phase responses. These filters provide strong suppression for use on low-elevation scans and yield low biases of velocity estimates so that accurate velocity dealiasing is possible. Specifically, the filters are designed for use in the Terminal Doppler Weather Radar (TDWR) and are shown to meet base data bias requirements equivalent to the Federal Aviation Administration’s specifications for the current TDWR clutter filters. Also an adaptive filter selection algorithm is proposed that bases its decision on clutter power estimated during an initial long-PRI surveillance scan. Simulations show that this adaptive algorithm yields satisfactory biases for reflectivity, velocity, and spectral width. Implementation of such a scheme would enable automatic elimination of anomalous propagation signals and constant adjustment to evolving ground clutter conditions, an improvement over the current TDWR clutter filtering system.

Polarimetric Doppler Weather Radar

2001 ◽  
Author(s):  
V. N. Bringi ◽  
V. Chandrasekar
Keyword(s):  
Weather Radar ◽  
Doppler Weather Radar

Modern Weather Surveillance Radars: Hygienic Aspects of Monitoring Electromagnetic Fields at Operators’ Workplaces and in the Environment

2020 ◽  
pp. 34-40
Author(s):  
VN Nikitina ◽  
GG Lyashko ◽  
NI Kalinina ◽  
EN Dubrovskaya ◽  
VP Plekhanov
Keyword(s):  
Electromagnetic Fields ◽  
Weather Radar ◽  
Measuring Instruments ◽  
Residential Areas ◽  
Emf Measurements ◽  
Operating Modes ◽  
Weather Radars ◽  
Radio Transmitters ◽  
Permissible Levels ◽  
Radar Antennas

Summary. Introduction: Location of weather surveillance radars near settlements, in residential areas and on airport premises makes it important to ensure safe levels of electromagnetic fields (EMF) when operating these radio transmitters. EMF maximum permissible levels for weather radars developed in the 1980s are outdated. Our objective was to analyze modern weather surveillance radars to develop proposals for improvement of radar-generated radiofrequency field monitoring. Materials and methods: We studied trends in meteorological radiolocation and technical characteristics of modern weather radars for atmospheric sensing and weather alerts, analyzed regulations for EMF measurements and hygienic assessment, and measured radiofrequency fields produced by weather radar antennas in open areas and at workplaces of operators. Results: We established that modern types of weather radars used in upper-air sensing systems and storm warning networks differ significantly in terms of technical characteristics and operating modes from previous generations. Developed in the 1980s, current hygienic standards for human exposures to radiofrequency fields from weather radar antennas are obsolete. Conclusions: It is essential to develop an up-to-date regulatory and method document specifying estimation and instrumental monitoring of EMF levels generated by weather radars and measuring instruments for monitoring of pulse-modulated electromagnetic radiation.

Terminal Doppler weather radar clutter control

2002 ◽  
Author(s):  
J.E. Evans ◽  
W.H. Drury ◽  
D.P. Hynek ◽  
T.S. Lee ◽  
B.H. Stevens
Keyword(s):  
Weather Radar ◽  
Doppler Weather Radar ◽  
Radar Clutter

Advanced Polarimetric Doppler Weather Radar Simulator

2014 ◽  
Author(s):  
S. Lischi ◽  
A. Lupidi ◽  
M. Martorella ◽  
F. Cuccoli ◽  
L. Facheris ◽  
...  
Keyword(s):  
Weather Radar ◽  
Doppler Weather Radar ◽  
Radar Simulator
Sign in / Sign up

Export Citation Format

Share Document