scholarly journals Sonic Detection and Ranging (SODAR) Wind Profiler Instrument Handbook

2016 ◽  
Author(s):  
Richard L. Coulter
Keyword(s):  
Wind Profiler ◽  
Sonic Detection

A NOVEL APPROACH TO IMPROVE THE WIND PROFILER DOPPLER SPECTRA USING WAVELETS

2016 ◽  
Vol 4 (4) ◽  
pp. 22
Author(s):  
MURTHY P. KRISHNA ◽  
REDDY S. NARAYANA ◽  
◽  
Keyword(s):  
Wind Profiler ◽  
Novel Approach

scholarly journals Wind shear over the Nice Côte d'Azur airport: case studies

2013 ◽  
Vol 13 (9) ◽  
pp. 2223-2238 ◽  
Author(s):  
A. Boilley ◽  
J.-F. Mahfouf
Keyword(s):  
Numerical Simulation ◽  
Numerical Model ◽  
Numerical Simulations ◽  
Wind Shear ◽  
Horizontal Wind ◽  
Wind Profiler ◽  
Measurement Campaign ◽  
Wind Lidar ◽  
Real Time Applications ◽  
Wind Shears

Abstract. The Nice Côte d'Azur international airport is subject to horizontal low-level wind shears. Detecting and predicting these hazards is a major concern for aircraft security. A measurement campaign took place over the Nice airport in 2009 including 4 anemometers, 1 wind lidar and 1 wind profiler. Two wind shear events were observed during this measurement campaign. Numerical simulations were carried out with Meso-NH in a configuration compatible with near-real time applications to determine the ability of the numerical model to predict these events and to study the meteorological situations generating an horizontal wind shear. A comparison between numerical simulation and the observation dataset is conducted in this paper.

scholarly journals Implementation of a 3-D-Var system for atmospheric profiling data assimilation into the RAMS model: initial results

2013 ◽  
Vol 6 (2) ◽  
pp. 3581-3610
Author(s):  
S. Federico
Keyword(s):  
Relative Humidity ◽  
Data Assimilation ◽  
Initial Conditions ◽  
Weather Prediction ◽  
Wind Profiler ◽  
Short Term ◽  
Recursive Filters ◽  
Data Assimilation System ◽  
Rams Model ◽  
Assimilation System

Abstract. This paper presents the current status of development of a three-dimensional variational data assimilation system. The system can be used with different numerical weather prediction models, but it is mainly designed to be coupled with the Regional Atmospheric Modelling System (RAMS). Analyses are given for the following parameters: zonal and meridional wind components, temperature, relative humidity, and geopotential height. Important features of the data assimilation system are the use of incremental formulation of the cost-function, and the use of an analysis space represented by recursive filters and eigenmodes of the vertical background error matrix. This matrix and the length-scale of the recursive filters are estimated by the National Meteorological Center (NMC) method. The data assimilation and forecasting system is applied to the real context of atmospheric profiling data assimilation, and in particular to the short-term wind prediction. The analyses are produced at 20 km horizontal resolution over central Europe and extend over the whole troposphere. Assimilated data are vertical soundings of wind, temperature, and relative humidity from radiosondes, and wind measurements of the European wind profiler network. Results show the validity of the analysis solutions because they are closer to the observations (lower RMSE) compared to the background (higher RMSE), and the differences of the RMSEs are consistent with the data assimilation settings. To quantify the impact of improved initial conditions on the short-term forecast, the analyses are used as initial conditions of a three-hours forecast of the RAMS model. In particular two sets of forecasts are produced: (a) the first uses the ECMWF analysis/forecast cycle as initial and boundary conditions; (b) the second uses the analyses produced by the 3-D-Var scheme as initial conditions, then is driven by the ECMWF forecast. The improvement is quantified by considering the horizontal components of the wind, which are measured at a-synoptic times by the European wind profiler network. The results show that the RMSE is effectively reduced at the short range (1–2 h). The results are in agreement with the set-up of the numerical experiment.

What Sound Can Be Expected From a Worn Tool?

1969 ◽  
Vol 91 (3) ◽  
pp. 525-534 ◽  
Author(s):  
E. J. Weller ◽  
H. M. Schrier ◽  
Bjorn Weichbrodt
Keyword(s):  
Machine Tool ◽  
Detection System ◽  
Cutting Edge ◽  
Cemented Carbide ◽  
Electronic Unit ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
Edge Wear ◽  
Sonic Detection ◽  
1045 Steel

This paper describes an electronic-mechanical system which utilizes sonic signals to detect the degree of cutting edge wear in metalworking tools and automatically trigger a cutting edge change. A packaged electronic unit reads out sonic vibrations from an instrumented machine-tool workpiece cutting-tool system to determine degree of cutting edge wear during a turning cut. At a predetermined comparative sonic ratio, the electronic unit commands stoppage of the machine tool feed, retraction of the tool and automatic index of the cemented carbide insert to the next good cutting edge. The latter function is performed by a prototype mechanical device. The paper describes the system and cites data generated during use of the sonic detection system with five grades of cemented carbide cutting AISI 1045 steel. Results under varying cutting conditions are reported. The authors speculate on the possibility of combining such a wear detection and cutting edge indexing arrangement with a computer to provide a complete system for optimum productivity and economy in a completely automatic operation.

scholarly journals Field test of a lidar wind profiler

1996 ◽  
Vol 35 (11) ◽  
pp. 3074 ◽  
Author(s):  
Gerard J. Kunz
Keyword(s):  
Field Test ◽  
Wind Profiler

scholarly journals Microphysical retrievals from simultaneous polarimetric and profiling radar observations

2009 ◽  
Vol 27 (12) ◽  
pp. 4435-4448 ◽  
Author(s):  
M. P. Morris ◽  
P. B. Chilson ◽  
T. J. Schuur ◽  
A. Ryzhkov
Keyword(s):  
Remote Sensing Data ◽  
Weather Radar ◽  
Ground Truth ◽  
Ambient Air ◽  
Exponential Model ◽  
Squall Line ◽  
Doppler Velocity ◽  
Wind Profiler ◽  
Polarimetric Weather Radar ◽  
Velocity Spectra

Abstract. The character of precipitation detected at the surface is the final product of many microphysical interactions in the cloud above, the combined effects of which may be characterized by the observed drop size distribution (DSD). This necessitates accurate retrieval of the DSD from remote sensing data, especially radar as it offers large areal coverage, high spatial resolution, and rigorous quality control and testing. Combined instrument observations with a UHF wind profiler, an S-band polarimetric weather radar, and a video disdrometer are analyzed for two squall line events occuring during the calendar year 2007. UHF profiler Doppler velocity spectra are used to estimate the DSD aloft, and are complemented by DSDs retrieved from an exponential model applied to polarimetric data. Ground truth is provided by the disdrometer. A complicating factor in the retrieval from UHF profiler spectra is the presence of ambient air motion, which can be corrected using the method proposed by Teshiba et al. (2009), in which a comparison between idealized Doppler spectra calculated from the DSDs retrieved from KOUN and those retrieved from contaminated wind profiler spectra is performed. It is found that DSDs measured using the distrometer at the surface and estimated using the wind profiler and polarimetric weather radar generally showed good agreement. The DSD retrievals using the wind profiler were improved when the estimates of the vertical wind were included into the analysis, thus supporting the method of Teshiba et al. (2009). Furthermore, the the study presents a method of investigating the time and height structure of DSDs.

scholarly journals Aspects of quality control of wind profiler measurements in complex topography

2014 ◽  
Vol 7 (1) ◽  
pp. 135-148 ◽  
Author(s):  
M. Maruri ◽  
J. A. Romo ◽  
L. Gomez
Keyword(s):  
Complex Terrain ◽  
Meteorological Conditions ◽  
Complex Signal ◽  
Wind Profiler ◽  
Complex Topography ◽  
Homogeneity Study ◽  
Homogeneity Assumption ◽  
Patterns Of Behavior ◽  
Wind Profiler Radar ◽  
Wind Profiles

Abstract. It is well known in the scientific community that some remote sensing instruments assume that sample volumes present homogeneous conditions within a defined meteorological profile. At complex topographic sites and under extreme meteorological conditions, this assumption may be fallible depending on the site, and it is more likely to fail in the lower layers of the atmosphere. This piece of work tests the homogeneity of the wind field over a boundary layer wind profiler radar located in complex terrain on the coast under different meteorological conditions. The results reveal the qualitative importance of being aware of deviations in this homogeneity assumption and evaluate its effect on the final product. Patterns of behavior in data have been identified in order to simplify the analysis of the complex signal registered. The quality information obtained from the homogeneity study under different meteorological conditions provides useful indicators for the best alternatives the system can offer to build wind profiles. Finally, the results are also to be considered in order to integrate them in a quality algorithm implemented at the product level.

Wind Profiler and RASS Measurements Compared with Measurements from a 450-m-Tall Tower

1998 ◽  
Vol 15 (3) ◽  
pp. 818-825 ◽  
Author(s):  
Wayne M. Angevine ◽  
Peter S. Bakwin ◽  
Kenneth J. Davis
Keyword(s):  
Wind Profiler ◽  
Tall Tower
Sign in / Sign up

Export Citation Format

Share Document