scholarly journals Meteorologically Stratified Gust Factors for Forecasting Peak Wind Gusts Across the United States

2021 ◽  
pp. 1-17
Author(s):  
Jonathan D. W. Kahl ◽  
Brandon R. Selbig ◽  
Austin R. Harris
Keyword(s):  
United States ◽  
Wind Speed ◽  
Power Distribution ◽  
The United States ◽  
Wind Gust ◽  
Average Wind Speed ◽  
Gust Factor ◽  
Wind Gusts ◽  
Wide Range ◽  
Gust Factors

AbstractWind gusts are common to everyday life and affect a wide range of interests including wind energy, structural design, forestry, and fire danger. Strong gusts are a common environmental hazard that can damage buildings, bridges, aircraft, and trains, and interrupt electric power distribution, air traffic, waterways transport, and port operations. Despite representing the component of wind most likely to be associated with serious and costly hazards, reliable forecasts of peak wind gusts have remained elusive. A project at the University of Wisconsin-Milwaukee is addressing the need for improved peak gust forecasts with the development of the meteorologically stratified gust factor (MSGF) model. The MSGF model combines gust factors (the ratio of peak wind gust to average wind speed) with wind speed and direction forecasts to predict hourly peak wind gusts. The MSGF method thus represents a simple, viable option for the operational prediction of peak wind gusts. Here we describe the results of a project designed to provide the site-specific gust factors necessary for operational use of the MSGF model at a large number of locations across the United States. Gust web diagrams depicting the wind speed- and wind direction-stratified gust factors, as well as peak gust climatologies, are presented for all sites analyzed.

scholarly journals Forecasting Peak Wind Gusts Using Meteorologically Stratified Gust Factors and MOS Guidance

2020 ◽  
Vol 35 (3) ◽  
pp. 1129-1143
Author(s):  
Jonathan D. W. Kahl
Keyword(s):  
Wind Speed ◽  
Weather Forecasting ◽  
Factor Model ◽  
Model Performance ◽  
The United States ◽  
Gust Factor ◽  
Wind Gusts ◽  
Skill Improvement ◽  
Model Output Statistics ◽  
Gust Factors

Abstract Gust prediction is an important element of weather forecasting services, yet reliable methods remain elusive. Peak wind gusts estimated by the meteorologically stratified gust factor (MSGF) model were evaluated at 15 locations across the United States during 2010–17. This model couples gust factors, site-specific climatological measures of “gustiness,” with wind speed and direction forecast guidance. The model was assessed using two forms of model output statistics (MOS) guidance at forecast projections ranging from 1 to 72 h. At 11 of 15 sites the MSGF model showed skill (improvement over climatology) in predicting peak gusts out to projections of 72 h. This has important implications for operational wind forecasting because the method can be utilized at any location for which the meteorologically stratified gust factors have been determined. During particularly windy conditions the MSGF model exhibited skill in predicting peak gusts at forecast projections ranging from 6 to 72 h at roughly half of the sites analyzed. Site characteristics and local wind climatologies were shown to exert impacts on gust factor model performance. The MSGF method represents a viable option for the operational prediction of peak wind gusts, although model performance will be sensitive to the quality of the necessary wind speed and direction forecasts.

scholarly journals An Examination of Tropical and Extratropical Gust Factors and the Associated Wind Speed Histograms

2005 ◽  
Vol 44 (2) ◽  
pp. 270-280 ◽  
Author(s):  
B. M. Paulsen ◽  
J. L. Schroeder
Keyword(s):  
Wind Speed ◽  
Tropical Cyclones ◽  
Deep Convection ◽  
Transitional Flow ◽  
Wind Gust ◽  
Measuring Device ◽  
Gust Factor ◽  
Mean Wind Speed ◽  
Landfalling Tropical Cyclones ◽  
Gust Factors

Abstract A gust factor, defined as the ratio between a peak wind gust and mean wind speed over a period of time, can be used along with other statistics to examine the structure of the wind. Gust factors are heavily dependent on upstream terrain conditions (roughness), but are also affected by transitional flow regimes (specifically, changes in terrain and the distance from the upstream terrain change to the measuring device), anemometer height, stability of the boundary layer, and, potentially, the presence of deep convection. Previous studies have yielded conflicting results regarding differences in gust factors that might exist between winds generated by tropical cyclones and those generated by extratropical systems. Using high-resolution wind speed data collected from both landfalling tropical cyclones and extratropical systems, two databases of wind characteristics were developed. Gust factors from tropical cyclone and extratropical winds were examined, summarized, and compared. Further analysis was conducted to examine and compare the characteristics of the associated tropical and extratropical wind speed histograms. As expected, the mean gust factor was found to increase with increasing upstream surface roughness. Some differences were observed between data from the tropical environment and the extratropical environment. Mean gust factors from the tropical regime were found to be higher than mean gust factors from the extratropical environment within each roughness regime and the wind speed histograms generated from data from the two environments indicated some differences.

scholarly journals Quantitative Assessment of Human Wind Speed Overestimation

2016 ◽  
Vol 55 (4) ◽  
pp. 1009-1020 ◽  
Author(s):  
Paul W. Miller ◽  
Alan W. Black ◽  
Castle A. Williams ◽  
John A. Knox
Keyword(s):  
United States ◽  
Wind Speed ◽  
General Rule ◽  
The United States ◽  
Daily Maximum ◽  
Wind Fields ◽  
Average Wind Speed ◽  
Spatial Homogeneity ◽  
Average Wind ◽  
Wind Events

AbstractHuman wind reports are a vital supplement to the relatively sparse network of automated weather stations in the United States, especially for localized convective winds. In this study, human wind estimates recorded in Storm Data between 1996 and 2013 were compared with instrumentally observed wind speeds from the Global Historical Climatology Network (GHCN). Nonconvective wind events in areas of flat terrain within the continental United States served as the basis for this analysis because of the relative spatial homogeneity of wind fields in these meteorological and geographic settings. The distribution of 6801 GHCN-measured gust factors (GF), defined here as the ratio of the daily maximum gust to the daily average wind, provided the reference upon which human gust reports were judged. GFs were also calculated for each human estimate by dividing the estimated gust by the GHCN average wind speed on that day. Human-reported GFs were disproportionately located in the upper tail of the observed GF distribution, suggesting that humans demonstrate a tendency to report statistically improbable wind gusts. As a general rule of thumb, humans overestimated nonconvective wind GFs by approximately one-third.

scholarly journals Wind and drifting-snow gust factor in an Alpine context

2011 ◽  
Vol 52 (58) ◽  
pp. 223-230 ◽  
Author(s):  
Florence Naaim-Bouvet ◽  
Mohamed Naaim ◽  
Hervé Bellot ◽  
Kouichi Nishimura
Keyword(s):  
Wind Tunnels ◽  
Wind Gust ◽  
Gust Factor ◽  
Wind Gusts ◽  
Drifting Snow ◽  
Order Of Magnitude ◽  
Snow Particle ◽  
Definition Of ◽  
S Peak ◽  
Gust Factors

AbstarctWind-transported snow is a common phenomenon in cold windy areas, creating snowdrifts and contributing significantly to the loading of avalanche release areas. It is therefore necessary to take into account snowdrift formation both in terms of predicting and controlling drift patterns. Particularly in an Alpine context, drifting snow is a nonstationary phenomenon, which has not been taken into account in physical modeling carried out in wind tunnels or in numerical simulations. Only a few studies have been conducted to address the relation between wind gusts and drifting-snow gusts. Consequently, the present study was conducted at the Lac Blanc pass (2700ma.s.l.) experimental site in the French Alps using a snow particle counter and a cup anemometer in order to investigate drifting-snow gusts. First, it was shown that the behavior of the wind gust factor was coherent with previous studies. Then the definition of wind gust factor was extended to a drifting-snow gust factor. Sporadic drifting-snow events were removed from the analysis to avoid artificially high drifting-snow gust factors. Two trends were identified: (1) A high 1 s peak and a mean 10 min drifting-snow gust factor, greater than expected, were observed for events that exhibited a gamma distribution on the particle width histogram. The values of drifting-snow gust factors decreased with increasing gust duration. (2) Small drifting-snow gusts (i.e. smaller than or of the same order of magnitude as wind gusts) were also observed. However, in this case, they were systematically characterized by a snow particle size distribution that differed from the two-parameter gamma probability density function.

scholarly journals Gust Factors: Meteorologically Stratified Climatology, Data Artifacts, and Utility in Forecasting Peak Gusts

2017 ◽  
Vol 56 (12) ◽  
pp. 3151-3166 ◽  
Author(s):  
Austin R. Harris ◽  
Jonathan D. W. Kahl
Keyword(s):  
Wind Speed ◽  
Meteorological Factors ◽  
Factor Models ◽  
Wind Gust ◽  
Gust Factor ◽  
Wind Measurements ◽  
The Mean ◽  
Substantial Bias ◽  
Wind Speed Forecast ◽  
Gust Factors

AbstractGust factors in Milwaukee, Wisconsin, are investigated using Automated Surface Observing System (ASOS) wind measurements from 2007 to 2014. Wind and gust observations reported in the standard hourly ASOS dataset are shown to contain substantial bias caused by sampling and reporting protocols that restrict the reporting of gusts to arbitrarily defined “gusty” periods occurring during small subsets of each hour. The hourly ASOS gust reports are found to be inadequate for describing the gust characteristics of the site and ill suited for the study of gust factors. A gust-factor climatology was established for Milwaukee using the higher-resolution, 1-min version of the ASOS dataset. The mean gust factor is 1.74. Stratified climatologies demonstrate that Milwaukee gust factors vary substantially with meteorological factors, with wind speed and wind direction exerting the strongest controls. A variety of modified gust-factor models were evaluated in which the peak wind gust is estimated by multiplying a gust factor by the observed, rather than forecast, wind speed. Errors thus obtained are entirely attributable to utility of the gust factor in forecasting peak gusts, having eliminated any error associated with the wind speed forecast. Results show that gust-factor models demonstrate skill in estimating peak gusts and improve with the use of meteorologically stratified gust factors.

scholarly journals Comparison of seven wind gust parameterizations over the European part of Russia

2018 ◽  
Vol 15 ◽  
pp. 251-255
Author(s):  
Maria Kurbatova ◽  
Konstantin Rubinstein ◽  
Inna Gubenko ◽  
Grigory Kurbatov
Keyword(s):  
Wind Speed ◽  
Skill Score ◽  
European Part ◽  
Probability Of Detection ◽  
Estimation Methods ◽  
Wind Gust ◽  
Average Wind Speed ◽  
Wind Gusts ◽  
European Part Of Russia ◽  
Temperature Profiler

Abstract. Wind gusts are extreme events which can cause severe damage. Gusts can reach significant values even during medium winds. However, numerical atmospheric models are designed to reproduce average wind speed, not gusts. There are several approaches to estimating wind gusts. Seven different methods are applied to WRF-ARW model output. Results are compared to high-frequency wind speed measurements using ultrasonic anemometers and temperature profiler measurement at the same point in Moscow. Data gathered from synoptic station network over the European part of Russia were also included in the analysis to increase the statistics. None of the wind gust estimation methods shows best results at every skill score. The proposed hybrid method shows good balance between the probability of detection and the false alarm ratio estimates.

The Politics of Precaution

2012 ◽  
Author(s):  
David Vogel
Keyword(s):  
United States ◽  
Animal Feed ◽  
The United States ◽  
Hazardous Substances ◽  
Risk Regulation ◽  
Scientific Certainty ◽  
European Public ◽  
Wide Range ◽  
Regulatory Controls ◽  
Milk Hormones

This book examines the politics of consumer and environmental risk regulation in the United States and Europe over the last five decades, explaining why America and Europe have often regulated a wide range of similar risks differently. It finds that between 1960 and 1990, American health, safety, and environmental regulations were more stringent, risk averse, comprehensive, and innovative than those adopted in Europe. But since around 1990 global regulatory leadership has shifted to Europe. What explains this striking reversal? This book takes an in-depth, comparative look at European and American policies toward a range of consumer and environmental risks, including vehicle air pollution, ozone depletion, climate change, beef and milk hormones, genetically modified agriculture, antibiotics in animal feed, pesticides, cosmetic safety, and hazardous substances in electronic products. The book traces how concerns over such risks—and pressure on political leaders to do something about them—have risen among the European public but declined among Americans. The book explores how policymakers in Europe have grown supportive of more stringent regulations while those in the United States have become sharply polarized along partisan lines. And as European policymakers have grown more willing to regulate risks on precautionary grounds, increasingly skeptical American policymakers have called for higher levels of scientific certainty before imposing additional regulatory controls on business.

Expansion of Groundnut ringspot virus Host and Geographic Ranges in Solanaceous Vegetables in Peninsular Florida

2011 ◽  
Vol 12 (1) ◽  
pp. 34 ◽  
Author(s):  
Craig G. Webster ◽  
William W. Turechek ◽  
H. Charles Mellinger ◽  
Galen Frantz ◽  
Nancy Roe ◽  
...  
Keyword(s):  
United States ◽  
The United States ◽  
Vegetable Production ◽  
Viral Pathogen ◽  
Geographic Ranges ◽  
First Report ◽  
Geographic Spread ◽  
Wide Range ◽  
Production Areas ◽  
Solanaceous Plants

To the best of our knowledge, this is the first report of GRSV infecting tomatillo and eggplant, and it is the first report of GRSV infecting pepper in the United States. This first identification of GRSV-infected crop plants in commercial fields in Palm Beach and Manatee Counties demonstrates the continuing geographic spread of the virus into additional vegetable production areas of Florida. This information indicates that a wide range of solanaceous plants is likely to be infected by this emerging viral pathogen in Florida and beyond. Accepted for publication 27 June 2011. Published 25 July 2011.

The Relations Between the Navy and the Foreign Service

1939 ◽  
Vol 33 (2) ◽  
pp. 283-291
Author(s):  
Clark H. Woodward
Keyword(s):  
United States ◽  
The United States ◽  
Government Agencies ◽  
National Defense ◽  
International Affairs ◽  
Proper Position ◽  
Foreign Service ◽  
Wide Range ◽  
National Emergency ◽  
The Relationship

In the conduct of foreign policy and the participation of the United States in international affairs, the relation between the Navy and the Foreign Service is of vital importance, but often misunderstood. The relationship encompasses the very wide range of coördination and coöperation which should and must exist between the two interdependent government agencies in peace, during times of national emergency, and, finally, when the country is engaged in actual warfare. The relationship involves, as well, the larger problem of national defense, and this cannot be ignored if the United States is to maintain its proper position in world affairs.

Small Screen, Big Feels

2020 ◽  
Author(s):  
Melissa Ames
Keyword(s):  
United States ◽  
The United States ◽  
Presidential Debates ◽  
Audience Studies ◽  
The Walking Dead ◽  
Wide Range ◽  
In Series ◽  
Fear And Anxiety ◽  
Small Screen ◽  
Network Era

While television has always played a role in recording and curating history, shaping cultural memory, and influencing public sentiment, the changing nature of the medium in the post-network era finds viewers experiencing and participating in this process in new ways. They skim through commercials, live tweet press conferences and award shows, and tune into reality shows to escape reality. This new era, defined by the heightened anxiety and fear ushered in by 9/11, has been documented by our media consumption, production, and reaction. In Small Screen, Big Feels, Melissa Ames asserts that TV has been instrumental in cultivating a shared memory of emotionally charged events unfolding in the United States since September 11, 2001. She analyzes specific shows and genres to illustrate the ways in which cultural fears are embedded into our entertainment in series such as The Walking Dead and Lost or critiqued through programs like The Daily Show. In the final section of the book, Ames provides three audience studies that showcase how viewers consume and circulate emotions in the post-network era: analyses of live tweets from Shonda Rhimes's drama, How to Get Away with Murder (2010--2020), ABC's reality franchises, The Bachelor (2002--present) and The Bachelorette (2003--present), and political coverage of the 2016 Presidential Debates. Though film has been closely studied through the lens of affect theory, little research has been done to apply the same methods to television. Engaging an impressively wide range of texts, genres, media, and formats, Ames offers a trenchant analysis of how televisual programming in the United States responded to and reinforced a cultural climate grounded in fear and anxiety.

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