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1.
Samanthi W. Durage Lina Kattan S. C. Wirasinghe Janaka Y. Ruwanpura 《Natural Hazards》2014,71(3):1495-1517
With increasing concerns over the possibility of tornadoes in highly populated areas in Canada, emergency managers are looking into ways to mitigate the impacts of tornadoes. Given that tornadoes can cause enormous destruction, early warnings and proper evacuation actions are critically important in helping save lives. In this paper, a survey was conducted to analyse the evacuation behaviour of households and drivers during a hypothetical tornado warning situation in the city of Calgary, Alberta. Nearly 500 Calgarians took part in the online survey and provided information on how they would respond to tornado warnings after receiving them. This paper presents the results of the survey. Using probit models, the factors influencing these evacuation decisions are identified and discussed in detail. The results of the household evacuation model show the importance of improving awareness about the safest locations during a tornado. It further highlights the need for targeting the population under the age of 30, who are more likely to take unsafe evacuation actions. The model for evacuation of drivers shows that several factors, such as knowing the difference between a watch and a warning, awareness of safe cover, receipt of warnings through natural environmental cues and the level of education, trigger evacuation actions in avoiding a tornado threat. 相似文献
2.
Weather-related disasters and affiliated losses in the USA have amplified over time. However, prior research using normalization schemes on damage tallies suggests that weather hazard losses are not necessarily rising when inflation, changes in wealth, and growth in population are accounted. This study evaluates the latter factor, assessing if population changes and a sprawling development mode have led to increasing potential for tornado disasters in the USA. Specifically, this research shows where and how quickly tornado exposure is growing by appraising spatiotemporal trends in gridded population and housing unit data for five metropolitan statistical areas (MSAs). The macroscale risk to tornadoes is represented by tornado day climatology and is related to the exposure of the five MSAs, which include Atlanta, GA; Chicago, IL; Dallas/Fort Worth, TX; Oklahoma City, OK; and St. Louis, MO. Supplementing the macroscale investigation, an observationally derived, hypothetical violent tornado track is transposed on various development types in each MSA to determine the microscale changes in human and built-environment exposure. Results demonstrate increased exposure in all MSAs at both the macro- and microscale. Of the five MSAs studied, Dallas, TX, had the greatest potential for a tornado disaster due to the higher risk for tornado occurrence comingling with the amount of MSA exposure. These results reveal further that amplifying exposure is a major impetus behind intensifying severe weather impacts and losses. 相似文献
3.
Cameron C. Lee 《Natural Hazards》2012,62(2):325-343
Previous research into the impacts of climate change on severe mid-latitude weather has been limited by the spatial resolution of many important variables in global climate model output. By utilizing synoptic climatological methods, however, this research takes an entirely different approach. Using a six-step process that includes principal components analysis, cluster analysis, and discriminant function analysis, this study first creates a continental-scale map pattern classification at three levels of the atmosphere, from geopotential height and temperature fields. These patterns are then associated to historic F2 and stronger United States?? tornado days using binary logistic regression. Using output data from two GCMs, spanning five different model emissions scenarios, this synoptic climatology of tornadoes is then utilized in order to project the changes in the frequency and seasonality of tornadic environments due to a changing climate. Results indicate that F2 and stronger US tornado days will increase anywhere from 3.8 to 12.7% by the 2090s. The majority of this increase is likely to be manifested in the earlier part of the tornado season. In addition to the shift in seasonality, a broadening of the peak tornado season is also noticed under some scenarios. Geographically, portions of the Northern and Central Plains, the High Plains, the Lower Great Lakes, the Mid-Atlantic States, and the Southeast are projected to experience an increase in tornado days under some future scenarios. The Upper Great Lakes states and the Southern Plains are projected to experience a decrease in tornado days. 相似文献
4.
James B. Elsner Richard J. Murnane Thomas H. Jagger Holly M. Widen 《Mathematical Geosciences》2013,45(6):667-679
The authors illustrate a statistical point process model that uses the spatial occurrence of nonviolent tornadoes to predict the distribution of the rare, violent tornadoes that occur during springtime across the US central Great Plains. The average rate of nonviolent tornadoes is 55 per 104 km2 per 62 years which compares with an average rate of only 1.5 violent tornadoes per 104 km2 over the same period (less than 3 %). Violent tornado report density peaks at 2.6 per 104 km2 (62 yr) in the city but is only 0.7 per 104 km2 in the countryside. The risk of a violent tornado is higher by a factor of 1.5, on average, in the vicinity of less violent tornadoes after accounting for the population bias. The model for the occurrence rate of violent tornadoes indicates that rates are lower by 10.3 (3.6, 16.5) % (95 % CI) for every 1 km increase in distance from the nearest nonviolent tornado, controlling for distance from the nearest city. Model significance and the distance-from-nearest nonviolent tornado parameter are not sensitive to population threshold or the definition of a violent tornado. The authors show that the model is useful for generating a catalogue of touchdown points that can be used as a component to a tornado catastrophe model. 相似文献
5.
Navid Attary John W. van de Lindt Hussam Mahmoud Steve Smith Christopher M. Navarro Yong Wook Kim Jong Sung Lee 《Natural Hazards》2018,93(3):1295-1316
Resiliency of communities prone to natural hazards can be enhanced through the use of risk-informed decision-making tools. These tools can provide community decision makers key information, thereby providing them the ability to consider an array of mitigation and/or recovery strategies. The Center for Risk-Based Community Resilience Planning, headquartered at Colorado State University in Fort Collins, Colorado, developed an Interdependent Networked Community Resilience (IN-CORE) computational environment. The purpose of developing this computational environment is to build a decision-support system, for professional risk planners and emergency responders, but even more focused on allowing researchers to explore community resilience science. The eventual goal was being to integrate a broad range of scientific, engineering and observational data to produce a detailed assessment of the potential impact of natural and man-made hazards for risk mitigation, planning and recovery purposes. The developing computational environment will be capable of simulating the effects from different natural hazards on the physical and socioeconomic sectors of a community, accounting for interdependencies between the sectors. However, in order to validate this computational tool, hindcasting of a real event was deemed necessary. Therefore, in this study, the community of Joplin, Missouri in the USA, which was hit by an EF-5 tornado on May 22, 2011, is modeled in the IN-CORE v1.0 computational environment. An explanation of the algorithm used within IN-CORE is also provided. This tornado was the costliest and deadliest single tornado in the USA in the last half century. Using IN-CORE, by uploading a detailed topological dataset of the community and the estimated tornado path combined with recently developed physics-based tornado fragilities, the damage caused by the tornado to all buildings in the city of Joplin was estimated. The results were compared with the damage reported from field studies following the event. This damage assessment was done using three hypothetical idealized tornado scenarios, and results show very good correlation with observed damage which will provide useful information to decision makers for community resilience planning. 相似文献
6.
Tornadoes are the most destructive winds created by nature. Sometimes tornadoes are strong enough to destroy most things in their path. These types of tornadoes are few compared to all tornadoes confirmed/reported. Currently, existing scales describe severity levels in terms of intensity/magnitude, and they are not sufficient to clearly distinguish the severity level. Several discrepancies between various sources of information complicate the interpretation of trends in tornado data. As a solution to these inconsistencies, a technique is required to compare the severity level of tornadoes. Impact factors, such as the number of fatalities, number of injuries, number of homeless, affected population, affected area, and cost of damage, can be considered to evaluate the severity levels. Prior experience, preparedness, awareness, evolving technology, mitigation methods, and early warning systems may minimize the number of fatalities and injuries. Models are used to identify which of the above factors should be considered in a severity scale to indicate the seriousness of tornadoes. However, the lack of data prevents an in-depth analysis of tornado severity. Extreme value theory is used to study potential severity levels of tornadoes. This paper attempts to develop an initial severity scale for tornadoes, which is a primary stage to develop a multi-dimensional severity scale. This common scale provides the criteria to rank tornadoes and allows the impact of one tornado to be compared to the impact of another tornado. Further, the scale allows the impact of a tornado to be compared to any type of natural disaster that occurs. 相似文献
7.
Anytime that tornadoes interface with people, the results are often grim. The varied characteristics of tornado windfields
and the diverse techniques of home construction complicate the expected outcomes of such interactions. Since it is now known
that tornadoes do not produce unfathomable winds, engineers have developed techniques for increasing a home’s tornado resistance;
thus, increasing the odds of survival of the inhabitants. Even considering these advances, tornadoes still wreak havoc and
cause much causality every year. The story of tornado survival is partly chance, partly knowledge, and partly science. This
essay utilizes analogies between a popular motion picture and the state of the art of tornado-resistant construction to illustrate
the good, the bad, and the ugly facts of tornado survival. First examined are the positive aspects of tornado probability.
The odds of experiencing a tornado are so low that massive expenditures are not necessarily cost effective. Next, various
techniques of tornado-resistant construction practices are included for new and existing structures. Introduction of equations
for predicting debris penetration are compared with various building techniques to describe the viability of tornado protection.
The negative aspect of tornado/structure interfaces describes the fact that despite contemporary construction and prevention
exercise, the unpredictability of the tornado windfield causes tremendous damage and loss of life. The final section examines
the interface between tornadoes and mobile homes. This proves very ugly in every aspect of the word. Statistics and equations
confirm the inherent dangers of such an interaction. Also, described is a novel approach to the design of a portable tornado
shelter. 相似文献
8.
Exploring probable reasons for record fatalities: the case of 2011 Joplin, Missouri, Tornado 总被引：1，自引：1，他引：0
On the evening of 22 May 2011, an EF-5 tornado tore a path six miles long across Joplin, Missouri, USA, killing 162 people as it passed through the heart of the city. This tornado stands as the deadliest single tornado to hit the United States since modern recordkeeping began in 1950, surpassing the tornado of 8 June 1953 that claimed 116 lives in Flint, Michigan. The record number of deaths caused by the single tornado in Joplin was far higher than the average annual number of US tornado deaths over the last three decades. This study explores the reasons for the high number of fatalities caused by the 2011 Joplin tornado. Questionnaire surveys administered among tornado survivors and informal discussions with emergency management personnel and others suggest that five reasons are associated with the high number of tornado fatalities experienced in Joplin: (1) the sheer magnitude of this event; (2) its path through commercial and densely populated residential areas; (3) the relatively large size of damage area; (4) the physical characteristics of affected homes in Joplin; and (5) the fact that some residents ignored tornado warnings. Several recommendations are offered, the implementation of which should reduce future tornado fatalities not only in Joplin, but elsewhere in the United States. 相似文献
9.
Tornadoes are one of the most powerful and destructive weather events. The frequency of tornado occurrence is highest in North America, especially in the US Canada is second only to the US, and approximately, 80 occurrences are reported annually. Communities are impacted only when and if a tornado touches down on the ground. Early recognition of tornadoes and proper communication of warnings in the pre-touchdown phase helps the public to be ready and respond appropriately and effectively. Given that tornadoes are hard to predict and the warnings give only a very brief window of opportunity to prepare for evacuation to a secure underground or other location, each activity in the detection and warning phases is critically important. This study is focused on conducting a detailed comparison of the tornado detection and warning systems in the US and Canada. The sequences of activities and their interrelationships in the tornado detection and warning systems of each country are identified and developed as networks. A detection and warning network for Canada is developed, using Calgary as a case study, whereas a separate network is developed for the US, showing how local residents receive tornado warnings initiated by a local weather forecast office. Moreover, collaborating partners are identified, and their involvement at each level of the information flow is recognized. The two networks are compared and critically analyzed, focusing on the key issues, such as prediction/detection capabilities, warning decision-making, warning dissemination methods, and the spotters’ role. This qualitative comparison supports the recognition of key areas that need to be considered in improving the tornado detection and warning system in Canada. 相似文献
10.
Motor vehicles historically have been dangerous locations to shelter in during tornado events. Throughout the twentieth century, motor vehicle design has become safer while tornado forecasting has become better understood. Despite such advances, tornado fatalities in motor vehicles still occur today, and some events periodically result in high numbers of deaths (e.g., ten motor vehicle occupants were killed by a single tornado in Garland, Texas, in 2015). We seek to examine all US tornado-induced motor vehicle fatalities documented between 1991 and 2015. Our findings indicate that motor vehicle fatalities have not significantly changed during this study period. We attribute annual fatality totals to persons lacking awareness of impending dangers coupled with numbers of significant tornado events for a given year. We find most fatalities result when vehicles are lofted or passengers are ejected, and this most typically occurs at the EF3–EF5 intensity thresholds. Fatalities that occur at weaker tornado winds (EF0–EF2) are most often attributed to collapsing debris (mostly trees) on vehicles. Spatially, motor vehicle fatalities are greatest in the Deep South and southern Great Plains regions where overall tornado and nighttime tornado frequencies are greatest. Some of the largest motor vehicle fatality events have resulted from tornadoes not being distinctly visible to motorists; such events have been characterized by tornadoes occurring at night or by tornadoes not appearing as “classic funnels.” 相似文献
11.
This paper reported a tornado hazard happened on June 23, 2016, in Yancheng city, Jiangsu Province. The moving footprint of this huge tornado was from west to east. Shuoji, Chenliang, Goudun, Banhu, Xingou, Wutan towns in Funing district and Sheyang town in Sheyang district were severely hit by this tornado. This tornado along with rainstorm and hailstorm had claimed 99 lives and caused more than 3800 flats to collapse as well as damaged 48 high-voltage circuits. As the cold air from northwest met the subtropical high pressure system that forms over relatively cool water bodies (i.e., Indian and Pacific Oceans), such a powerful meteorological phenomenon was initiated. The strong connective airflow intensified the development of this tornado. Based on the preliminary investigation and analysis of this tornado, cost-effective timber structures with adequate anchorage of the framing to foundations and adequate connection between walls and roofs may be recommended to ensure occupants safety and reduce potential damage in these extreme wind events. Additionally, it is suggested to utilize early warning system along with geographical information system (GIS), Global Positioning System (GPS), and remote sensing (RS) (3S) to monitor and precast the occurrence of rainfall, hailstorm, and tornado hazards in future.
相似文献12.
Krocak Makenzie J. Ernst Sean Allan Jinan N. Wehde Wesley Ripberger Joseph T. Silva Carol L. Jenkins-Smith Hank C. 《Natural Hazards》2020,102(3):1351-1368
When the National Weather Service (NWS) issues a tornado warning, the alert is rapidly and widely disseminated to individuals in the general area of the warning. Historically, the assumption has been that a false-negative warning perception (i.e., when someone located within a warning polygon does not believe they have received a tornado warning) carries a higher cost than a false-positive warning perception (i.e., when someone located outside the warning area believes they have received a warning). While many studies investigate tornado warning false alarms (i.e., when the NWS issues a tornado warning, but a tornado does not actually occur), less work focuses on studying individuals outside of the warning polygon bounds who believe they received a warning (i.e., false-positive perceptions). This work attempts to quantify the occurrence of false-positive perceptions and possible factors associated with the rate of occurrence. Following two separate storm events, Oklahomans were asked whether they perceived a tornado warning. Their geolocated responses were then compared to issued warning polygons. Individuals closer to tornado warnings or within a different type of warning (e.g., a severe thunderstorm warning) are more likely to report a false-positive perception than those farther away or outside of other hazard warnings. Further work is needed to understand the rate of false-positive perceptions across different hazards and how this may influence warning response and trust in the National Weather Service.
相似文献13.
Kevin D. Ash 《GeoJournal》2017,82(3):533-552
Occupants of mobile or manufactured homes in the United States of America (USA) are highly exposed and susceptible to injury or death from tornado hazards. This problem is most pronounced in the southern and eastern USA, where tornadoes are frequent and mobile homes comprise upwards of 15 % of the housing stock. Recognizing this vulnerability, emergency management entities and the USA National Weather Service often recommend that mobile home residents evacuate to a nearby sturdy building or a specially-built tornado shelter when tornadoes threaten their communities. Previous research suggests, however, that only 30 % of residents follow this recommendation. In this research I aim to provide insight as to why many mobile home residents seldom undertake the suggested course of action for tornadoes. Using excerpts from twenty semi-structured interviews conducted during 2013 in South Carolina, I show that some individuals understand physical characteristics of tornadoes very differently than experts do. In addition, mobile home residents may also hold views that differ from experts about the ability of their homes to withstand tornadic winds and debris. Even if mobile home occupants pay close attention to thunderstorm hazards and might be willing to evacuate, they may prioritize protective actions for lightning or flash flooding over those recommended for tornadoes. Finally, the interviews reveal that there is much confusion over where to go, when to leave, and which route to take to arrive safely at a sheltering place for tornado hazards. I discuss some of the potential ramifications of the findings for theory and practice and suggest how future research might build on this work. 相似文献
14.
Sergey A. Arsen’yev 《地学前缘(英文版)》2011,2(2):215-221
Recent advances in modeling of tornadoes and twisters consist of significant achievements in mathematical calculation of occurrence and evolution of a violent F5-class tornado on the Fujita scale, and four-dimensional mathematical modeling of a tornado with the fourth coordinate time multiplied by its characteristic velocity.Such a tornado can arise in a thunderstorm supercell filled with turbulent whirlwinds.A theory of the squall storms is proposed.The squall storm is modeled by running perturbation of... 相似文献
15.
A May 2007 tornado destroyed 95% of aging, declining Greensburg, Kansas. The city took the opportunity to build back “stronger,
better, and greener,” enforcing upgraded codes, requiring city-owned buildings to meet LEED Platinum level standards, and
recommending energy-efficiency housing in a new Sustainable Comprehensive Plan. Using information collected from surveys of
Greensburg tornado survivors, interviews, and publications, we examined the housing-related recovery, including the emergency
provision of temporary shelter and rebuilding permanently. Although temporary shelter kept residents nearby for rebuilding,
given the gap between insurance policy limits on the aging housing stock and rebuilding costs, housing affordability is a
critical issue in Greensburg’s recovery. Local, state, and federal support have made construction of municipal buildings at
LEED Platinum level and some affordable and green housing projects possible. However, far greater public and private sector
funding for affordable workforce housing, in conjunction with broader economic and job development, is needed. 相似文献
16.
This research provides an overview and discussion of language used in tornado safety recommendations along with development of a rubric for scaled tornado safety recommendations. Residents living in affected areas and those temporarily housed at relief stations were surveyed to collect information on their experiences during a 2-week period following the April 27, 2011 Tuscaloosa, Alabama EF4 tornado. Respondents were asked about their refuge plans during the storm and about any future changes to those plans. A specific focus of this research evaluated the adequacy of each respondent’s plan. Each refuge plan was compared using a tornado refuge rubric developed through the use of enhanced Fujita (EF) scale degree of damage ratings for available damage indicators. There was a significant difference in the counts of refuge adequacy for Tuscaloosa residents when holding the locations during the April 27 tornado constant and comparing adequacy ratings for weak (EF0–EF1), strong (EF2–EF3), and violent (EF4–EF5) tornadoes. There was also a significant difference when comparing the future tornado refuge plans of those same participants to the adequacy ratings for weak, strong, and violent tornadoes. This research introduces renewed discussion on proper refuge and shelter alternatives for days when violent tornadoes are forecasted. 相似文献
17.
Tornado fatalities and mobile homes in the United States 总被引：1，自引：1，他引：0
Fatalities from tornadoes have declined dramatically over the last century in the United States. Despite the overall reduction
in tornado lethality, fatalities from mobile homes remain high. In fact, research suggests that the likelihood of a fatality
in a mobile home is ten times or more than that in a permanent home. This study examines possible explanations of the mobile
home tornado problem, including the potential for concentration of these homes in tornado prone states, the relation to Fujita
Scale rating, and incidence during the day. We find that mobile home fatalities are concentrated in the Southeastern US, significantly
more likely in weaker tornadoes, and occur disproportionately at night. 相似文献
18.
Mariano Angelo Zanini Lorenzo Hofer Flora Faleschini Carlo Pellegrino 《Natural Hazards》2017,86(3):1247-1273
A tornado with severe intensity hit the municipalities of Pianiga, Dolo and Mira close to Venice, northeast Italy, causing damages on a wide number of residential and industrial buildings and destroying some historical villas. In this study, the authors show the results of the damage assessment survey performed in the first days after the occurrence of the extreme event. Limited literature deals with damage assessment of European building types due to wind actions, and the available one does not consider building vulnerability as key factor in the structural response of existing structures subject to tornado hazard. In this paper, structural damages surveyed in reinforced concrete frame structures and masonry buildings, representative of common Italian building types, are critically discussed. Additionally, this work provides a database of past tornado events in northeast Italy, evidencing how the analyzed area has been found to be quite prone to tornado hazard. 相似文献
19.
Richard H. D. McRae Jason J. Sharples Stephen R. Wilkes Alan Walker 《Natural Hazards》2013,65(3):1801-1811
On 18 January 2003, fires had a devastating impact on Australia’s capital, Canberra. A series of reviews and scientific studies have examined the events of that day and indicate that the worst impacts were due to a series of violent pyro-convective events and resultant pyro-cumulonmibi. These coupled fire–atmosphere events are much more energetic than normal fires. In one instance, an intense pyro-convective cell developed a tornado. We demonstrate that this was indeed a tornado, the first confirmed pyro-tornadogenesis in Australia, and not a fire whirl. Here, we discuss aspects of the formation, evolution and decay of the tornado, which was estimated to have been of at least F2 intensity, highlighting a process that can significantly increase the damage of a wildfire event. 相似文献
20.
Tornadoes have been reported in various places around the world. The United States has the greatest number of tornado reports. In South America, tornadoes have been reported in Argentina and neighboring countries, such as Chile, Brazil, and Uruguay. There are no reports of tornadoes in Colombia in the worldwide databases. The first reported tornado event in Colombia took place in 2001. Since then, four tornados have affected the northern part of Colombia. The aim of this study is to characterize the events reported on the Caribbean coast of Colombia and their relation to local climate conditions. Before 2001, we had no knowledge regarding tornadoes in this area. However, during the past 10?years, these atmospheric phenomena have occurred in Barranquilla and the surrounding metropolitan area. Worldwide databases on tornadoes have not registered any such events in this part of South America. A review of the atmospheric information was conducted to determine the influence of air temperature increases on tornado formation. This study reveals that tornadoes have appeared between May and September, the months during which the city experiences the hottest temperatures of the year. The most significant tornado took place on September 15, 2006. This tornado lasted 15?min and travelled almost 10?km. Of the four registered tornadoes, this was the only one to affect the residential area of the city. The other three affected only the suburbs located in the surrounding metropolitan area. The most recent phenomenon related with tornadoes took place between July and August of 2010, during which three tornadoes could have potentially formed. However, a vortex never made contact with the ground. This meteorological analysis is very basic because climate information for these areas is limited. Still, what information we have reveals conditions that are typical of tornado formation: a mass of cold air combined with high air temperatures in a specific area. The data analysis reveals that tornados have occurred between May and June. These months correspond to the period characterized by the highest temperatures: average temperatures of 28.2?°C and maximum temperatures of 33.2?°C. This is also the period characterized by the greatest relative humidity and precipitation (84?% and 50?mm, respectively). Because the tornadoes reports only appeared in the last 10?years, it is not possible to determine whether there is a realistic relationship between their occurrence and large-scale climatic change. This article characterizes tornadoes as a new environmental threat and not an isolated phenomenon for this part of Colombia. Tornadoes in this region should thus be included in global databases. 相似文献