Understanding the Influence of Climate Elements on Traffic Behavior: The Wind Impact Approach

Author(s):  
Ivana Sentić ◽  
Jasmina Đorđević ◽  
Tijana Đorđević ◽  
Mirjana Ljubojević ◽  
Jelena Čukanović

Abstract Due to intense highway congestion in Europe, increased percentage of highway accidents, as well as mortality rate, safety is an imperative in highway planning and design. Highway design safety standards have been researched extensively, but not enough attention has been paid to the surrounding environmental impacts, foremost climate elements. Therefore, this research attempts to understand the least researched climate element — the wind, and its impact on highway safety. The highway landscape falls under the category of the wind impacts that can cause significant problems for the drivers throughout the year. The values for wind direction, frequency and intensity were taken from the CARPATCLIM database. The evaluation of homogenized and harmonized set of data on a daily basis for a twenty-year period documented a variety of wind impacts on highway safety. It was found that the wind is constantly present throughout the year, with specific monthly oscillations. By using the ArcGis and the interpolation method, it has been clearly observed at which points the effect of intense winds was present the most. In order to understand the overall image of highway safety, fieldwork was conducted in various meteorological conditions. The checklists photo-documented and qualitatively described the observed extreme wind events (alone or combined with one more climate element). Based on everything described above, the image of the current situation was provided, and the proposal for control of the impact of wind using an adequate vegetation assembly (windbreaks) has been offered.

2014 ◽  
Vol 53 (11) ◽  
pp. 2417-2429 ◽  
Author(s):  
S. C. Pryor ◽  
R. Conrick ◽  
C. Miller ◽  
J. Tytell ◽  
R. J. Barthelmie

AbstractThe scale and intensity of extreme wind events have tremendous relevance to determining the impact on infrastructure and natural and managed ecosystems. Analyses presented herein show the following. 1) Wind speeds in excess of the station-specific 95th percentile are coherent over distances of up to 1000 km over the eastern United States, which implies that the drivers of high wind speeds are manifest at the synoptic scale. 2) Although cold fronts associated with extratropical cyclones are a major cause of high–wind speed events, maximum sustained and gust wind speeds are only weakly dependent on the near-surface horizontal temperature gradient across the front. 3) Gust factors (GF) over the eastern United States have a mean value of 1.57 and conform to a lognormal probability distribution, and the relationship between maximum observed GF and sustained wind speed conforms to a power law with coefficients of 5.91 and −0.499. Even though there is coherence in the occurrence of intense wind speeds at the synoptic scale, the intensity and spatial extent of extreme wind events are not fully characterized even by the dense meteorological networks deployed by the National Weather Service. Seismic data from the USArray, a program within the Earthscope initiative, may be suitable for use in mapping high-wind and gust events, however. It is shown that the seismic channels exhibit well-defined spectral signatures under conditions of high wind, with a variance peak at frequencies of ~0.04 s−1 and an amplitude that appears to scale with the magnitude of observed wind gusts.


1990 ◽  
Vol 17 (1) ◽  
pp. 79-86 ◽  
Author(s):  
John Morrall ◽  
Wayne Thompson

This paper describes the techniques used in the planning and design of a system of passing lanes for the Trans-Canada Highway in Yoho National Park. The techniques, which include a traffic simulation model, were developed to allow the evaluation of the impact of low-cost operational improvements such as passing lanes on the level of service. The traffic simulation model allowed the investigation of a wide range of highway alternatives in addition to changes in traffic flow, traffic stream characteristics, and vehicle performance characteristics. The passing lane designs described in the paper are based on the concept of incorporating passing lanes within the existing highway cross section. The design concept has evolved from the experimental passing lane project in Banff. In addition to geometric design, signing, and road marking guidelines, warrants for bicycle lanes on the Trans-Canada Highway are also presented. Key words: highway planning and engineering, two-lane highways, traffic simulation model, level of service, passing lanes, Trans-Canada Highway.


CICTP 2020 ◽  
2020 ◽  
Author(s):  
Xiaofei Wang ◽  
Jiangbei Yao ◽  
Zhengkai Li ◽  
Yuntao Liu ◽  
Jin Cai

2021 ◽  
Vol 18 (6) ◽  
pp. 1405-1423
Author(s):  
Dariusz Strzyżowski ◽  
Elżbieta Gorczyca ◽  
Kazimierz Krzemień ◽  
Mirosław Żelazny

AbstractStrong wind events frequently result in creating large areas of windthrow, which causes abrupt environmental changes. Bare soil surfaces within pits and root plates potentially expose soil to erosion. Absence of forest may alter the dynamics of water circulation. In this study we attempt to answer the question of whether extensive windthrows influence the magnitude of geomorphic processes in 6 small second- to third-order catchments with area ranging from 0.09 km2 to 0.8 km2. Three of the catchments were significantly affected by a windthrow which occurred in December 2013 in the Polish part of the Tatra Mountains, and the other three catchments were mostly forested and served as control catchments. We mapped the pits created by the windthrow and the linear scars created by salvage logging operations in search of any signs of erosion within them. We also mapped all post-windthrow landslides created in the windthrow-affected catchments. The impact of the windthrow on the fluvial system was investigated by measuring a set of channel characteristics and determining bedload transport intensity using painted tracers in all the windthrow-affected and control catchments. Both pits and linear scars created by harvesting tend to become overgrown by vegetation in the first several years after the windthrow. The only signs of erosion were observed in 10% of the pits located on convergent slopes. During the period from the windthrow event in 2013 until 2019, 5 very small (total area <100 m2) shallow landslides were created. The mean distance of bedload transport was similar (t-test, p=0.05) in most of the windthrow-affected and control catchments. The mapping of channels revealed many cases of root plates fallen into a channel and pits created near a channel. A significant amount of woody debris delivered into the channels influenced the activity of fluvial processes by creating alternating zones of erosion and accumulation.


2021 ◽  
Vol 9 (3) ◽  
pp. 246
Author(s):  
Difu Sun ◽  
Junqiang Song ◽  
Xiaoyong Li ◽  
Kaijun Ren ◽  
Hongze Leng

A wave state related sea surface roughness parameterization scheme that takes into account the impact of sea foam is proposed in this study. Using eight observational datasets, the performances of two most widely used wave state related parameterizations are examined under various wave conditions. Based on the different performances of two wave state related parameterizations under different wave state, and by introducing the effect of sea foam, a new sea surface roughness parameterization suitable for low to extreme wind conditions is proposed. The behaviors of drag coefficient predicted by the proposed parameterization match the field and laboratory measurements well. It is shown that the drag coefficient increases with the increasing wind speed under low and moderate wind speed conditions, and then decreases with increasing wind speed, due to the effect of sea foam under high wind speed conditions. The maximum values of the drag coefficient are reached when the 10 m wind speeds are in the range of 30–35 m/s.


2016 ◽  
Vol 31 (3) ◽  
pp. 985-1000 ◽  
Author(s):  
Nicholas J. Weber ◽  
Matthew A. Lazzara ◽  
Linda M. Keller ◽  
John J. Cassano

Abstract Numerous incidents of structural damage at the U.S. Antarctic Program’s (USAP) McMurdo Station due to extreme wind events (EWEs) have been reported over the past decade. Utilizing nearly 20 yr (~1992–2013) of University of Wisconsin automatic weather station (AWS) data from three different stations in the Ross Island region (Pegasus North, Pegasus South, and Willie Field), statistical analysis shows no significant trends in EWE frequency, intensity, or duration. EWEs more frequently occur during the transition seasons. To assess the dynamical environment of these EWEs, Antarctic Mesoscale Prediction System (AMPS) forecast back trajectories are computed and analyzed in conjunction with several other AMPS fields for the strongest events at McMurdo Station. The synoptic analysis reveals that McMurdo Station EWEs are nearly always associated with strong southerly flow due to an approaching Ross Sea cyclone and an upper-level trough around Cape Adare. A Ross Ice Shelf air stream (RAS) environment is created with enhanced barrier winds along the Transantarctic Mountains, downslope winds in the lee of the glaciers and local topography, and a tip jet effect around Ross Island. The position and intensity of these Ross Sea cyclones are most influenced by the occurrence of a central Pacific ENSO event, which causes the upper-level trough to move westward. An approaching surface cyclone would then be in position to trigger an event, depending on how the wind direction and speed impinges on the complex topography around McMurdo Station.


PEDIATRICS ◽  
1993 ◽  
Vol 91 (1) ◽  
pp. 234-236
Author(s):  
Sue Bredekamp

Any discussion of standards, no matter how brief, must first acknowledge that there are different types of standards established for different purposes. As the director of the national voluntary accreditation system for child care centers and schools established by the National Association for the Education of Young Children (NAEYC), I am most familiar with the need and impact of accreditation standards, which are, by definition, standards for distinguishing high-quality programs established by a professional organization. In any case the implementation of a national accreditation system is heavily influenced by local and state licensing standards, which are mandatory government regulations that establish a baseline of protection. Accreditation and licensing standards are both influenced by model standards such as the health and safety standards of the American Academy of Pediatrics and the American Public Health Association.1 These standards establish a model, based on the best professional evidence, that serves as a reference for the other two systems but does not carry an enforcement system of its own. This paper will discuss the need for and impact of all three types of standards from the point of view of my experience in operating NAEYC's accreditation system.2 Because our accreditation process is nationally administered, we have the opportunity to observe the impact of diverse licensing standards on quality. In order to maintain accessibility we have relatively few eligibility requirements, and because we do not require 100% compliance with our criteria, we also have the opportunity to observe the interrelationships among standards and other effects. One caveat must be offered at the outset.


Buildings ◽  
2016 ◽  
Vol 6 (4) ◽  
pp. 48 ◽  
Author(s):  
Peter Wootton-Beard ◽  
Yangang Xing ◽  
Raghavalu Durai Prabhakaran ◽  
Paul Robson ◽  
Maurice Bosch ◽  
...  

Author(s):  
Jieling Xiao ◽  
Andrew Hilton

Square dancing is a popular music-related group physical exercise for health benefits in China mainly participated by mid-aged women and elderly people. This paper investigates the soundscape and enjoyment of the square dancing in urban streets through a case study in Lichuan, a county level city in southwest China, in December 2017. It examines the impact of gender, age, participation and places on perceptions of square dancing soundscape. Two sites along two main urban streets in the city were selected to conduct onsite investigations where residents spontaneously perform square dancing on a daily basis. Ethnographical observations were conducted to identify the social-physical features and sounds of both sites during the dance and without dance. Sound pressure measurements (LAeq and LAmax) were also conducted under the two conditions. An off-site survey was distributed through the local social media groups to understand residents’ everyday experiences and perceptions of square dancing in the city; 106 responses were received for the off-site survey. T-tests and Chi-squared tests were used for statistical analysis of the survey data. The results show gender does appear to be a factor influencing the regularity of participation in square dancing, with a bias towards more female participants. Participation frequency of square dance has an impact on the enjoyment of square dancing. There is no correlation between the dislike of watching square dancing, or dislike of the music and a desire to restrict locations for square dancing.


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