Comparing reactions to two severe tornadoes in one Oklahoma community

The authors compared the effect of the 3 May 1999 F5 and 8 May 2003 F3 tornadoes on the community of Moore, Oklahoma, by canvassing damaged areas after both tornadoes and surveying residents. Significantly more 1999 than 2003 residents reported property damage and injuries. Television and tornado sirens were the most common warnings each year, however, more 1999 residents received and responded to television warnings. Importantly, storm shelters were used more frequently in 2003. Fifty-one per cent of residents who experienced both tornadoes took the same amount of protective action in 2003 as they had in 1999; 22% took less; and 27% took more. Residents who took less action said that the reason for doing so was inadequate warning and shelter. First-hand experience of tornadoes prompts people to heed warnings when adequate notification is received and to take effective protective action when adequate shelter is available.     

龙卷风风灾的调查与评估

以江苏省为例搜集并核实了最近３７年间龙卷风的事实和灾情资料，尝试性地采用专家评分方式从风灾实况对各次龙卷风的强度进行了富士达级别评定，论证了这种从具有模糊性的灾情事实中提取半定量信息方法的客观性。结果发现，各强度级别是龙卷风的累积分布可近似用两段指数函数拟合。在此基础上，定量地给出了江苏省龙卷风频率和强度的地域分布，各级龙卷风的平均再现间隔年数等统计指标。     

Normalized tornado damage in the United States: 1950–2011

In 2011, thunderstorms in the United States resulted in 550 deaths from tornadoes and more than $28 billion in property damage, according to data from the US National Oceanic and Atmospheric Administration, with the vast majority of economic losses resulting from tornadoes. This article normalizes U.S. tornado damage from 1950 to 2011, using several methods. A normalization provides an estimate of the damage that would occur if past events occurred under a common base year's societal conditions. We normalize for changes in inflation and wealth at the national level and changes in population, income and housing units at the county level. Under several methods, there has been a sharp decline in tornado damage. This decline corresponds with a decline in the reported frequency of the most intense (and thus most damaging) tornadoes since 1950. However, quantification of trends in tornado incidence is made difficult due to discontinuities in the reporting of events over time. The normalized damage results are suggestive that some part of this decline may reflect actual changes in tornado incidence, beyond changes in reporting practices. In historical context, 2011 stands out as one of the most damaging years of the past 61 years and provides an indication that maximum damage levels have the potential to increase should societal change lead to increasing exposure of wealth and property.     

Predictors for people's response to a tornado warning: Arkansas, 1 March 1997

On 1 March 1997, powerful tornadoes touched down in Arkansas (USA) on a Saturday afternoon. Twenty-six fatalities and 400 non-fatal injuries were reported. We performed a population-based cross-sectional study to determine factors associated with appropriate responses to tornado warnings. Of 146 survey participants, 140 (96 per cent) knew the difference between 'tornado watch' and 'tornado warning' and were aware of when the warning was announced. Of those 140 participants, 64 (45.7 per cent) responded to the warning by seeking shelter, and 58 (90.6 per cent) of those 64 acted within five minutes of hearing the warning. Four factors were positively associated with those seeking shelter: having graduated from high school (OR = 4.2, 95 per cent CI = 1.1-15.5); having a basement in one's house (OR = 3.8, 95 per cent exact CI = 1.1-17.1); hearing a siren (OR = 4.4, 95 per cent CI = 1.3-18.9); and having prepared a household plan of response when tornadoes occur (OR = 2.6, 95 per cent CI = 1.1-6.3). On the basis of these findings, we recommend: first, that people who live in tornadoprone areas have a personal plan of action to help them respond immediately to warnings; second, public-health education officials in areas with frequent tornadic activity should do more to educate the public about what they can do to protect themselves from a tornado; and third, that emergency-management officials planning protection measures for vulnerable communities should consider that most people have limited time (our study documented five minutes) in which to respond to a tornado warning. Thus, shelters in tornado-prone areas should be quickly accessible by residents.     

Predictors of compliance with tornado warnings issued in Joplin,Missouri, in 2011

Joplin, a city in the southwest corner of Missouri, United States, suffered an EF‐5 tornado in the late afternoon of 22 May 2011. This event, which claimed the lives of 162 people, represents the deadliest single tornado to strike the US since modern record‐keeping began in 1950. This study examines the factors associated with responses to tornado warnings. Based on a post‐tornado survey of survivors in Joplin, it reveals that tornado warnings were adequate and timely. Multivariate logistic regression identified four statistically significant determinants of compliance with tornado warnings: number of warning sources, whether respondents were at home when the tornado struck, past tornado experience, and gender. The findings suggest several recommendations, the implementation of which will further improve responses to tornado warnings.     

Perception of earthquake risk in Agadir,Morocco: A case study from a Muslim community

Earthquakes are separated from other hazards in meaning, significance, and risk perception throughout the Islamic World due to their specific focus in their own chapter or surah “al-Zalzala” (99th) in the Qur'an. Unlike earthquakes that are discussed in terms or the Judgment Day or as divine punishment or retribution against the disbelieving or hypocritical—other natural hazards like floods, tornadoes, and landslides are rarely discussed. An extensive survey of earthquake survivors and longtime residents was undertaken to better understand the perceptions of seismic risk in Agadir, Morocco where two moderate earthquakes razed the city in 1960 leaving 15,000 dead and 25,000 injured. Most of the deaths were attributed to faulty construction (along with standards and enforcement), inaddition to poor evacuation plans.

During the summer of 2002, more than 250 earthquake survivors and residents were surveyed and interviewed for their knowledge and perception of the disaster forty years before. Surveys were conducted in Arabic, French and English and included questions and Likertscaled responses including extensive interviews in the hopes of obtaining ideas of their potential quake recurrence, seismology, current construction standard policies, and local and regional planning strategies. In addition, reviews the Qur'an, Hadith and classical and contemporary tafasir texts were used to investigate the guiding passages used in Islamic discussions of “al-Zalzala”.

It was found that younger persons (<25yo) were more likely to believed that brick, mortar and cement structures were always safer and stronger during and after a tremor, regardless as to whether they are iron-reinforced or sub-standard (and hazardous) stone or brick infilled. After the 1960 disaster, speedy recovery efforts often undermined concrete construction and reinforcement techniques since such ‘rebar’ was relatively unavailable. Even today, inferior and seismically unstable construction practices are widely used.

It was found that television-watchers considered themselves less knowledgeable about earthquakes, when in fact many aspects of the1960 event and earthquakes in general, were more widely understood by this group, supporting the notion that the medium of televisionis the most widely used, efficient, and fastest mass communication and education tool.

Less-educated respondents in general tended to attribute earthquakes to divine action and retribution. All questions, however, concerning the possibility of quake recurrence frequency or magnitude caused an overwhelming refusal to answer, or with the reply of ‘Allahu a'lam’ or “God is wisest”—implying or directly stating that any attempt at earthquake forecasting, quake-related construction, advanced architectural standards for seismic safety, and/or related education was ‘haram’ or prohibited by Islam.

Further discussions with participants in Agadir indicated that any guess, awareness or prediction was in fact, fortune-telling and therefore an act forbidden by the Qur'an and Hadith.

Finally, the less educated were more likely to say that Allah protected those who were devout and considered scientific assessment as futile, forecasting as forbidden, or new construction technologies as a waste since only the ‘kafir’ (non-Muslim) or ‘munafiq’ (hypocrite) were at risk to death or injury from an earthquake. These conclusions are important toward gaining an insight of perception and risky behavior in a questionably constructed city with now more than 600,000 people 40 years later, and in a region laced by active faulting.     

Facebook and Twitter,communication and shelter,and the 2011 Tuscaloosa tornado

This paper represents one of the first attempts to analyse the many ways in which Facebook and Twitter were used during a tornado disaster. Comparisons between five randomly selected campus samples and a city of Tuscaloosa, Alabama, sample revealed that campus samples used Facebook and Twitter significantly more both before and after the tornado, but Facebook usage was not significantly different after the event. Furthermore, differences in social media usage and other forms of communication before the tornado were found for age, education, and years lived in Tuscaloosa. Generally, age and education were inversely proportionate to social media usage. Influences on shelter‐seeking actions varied between social media users and three random samples of non‐social media users; however, it appears that social media respondents were likely to be using a smartphone simultaneously to access warning polygon information, to receive text message alerts, and to listen or respond to environmental cues.     

Vehicle-occupant deaths caused by tornadoes in the United States, 1900–1998

Abstract

Occupants of vehicles encounter an uncertain degree of risk during tornadic storms. The current National Weather Service guidelines suggest we abandon vehicles to lie in a ditch if no sturdy shelter is available. However, these guidelines were developed without the benefit of supporting research. As we are an increasingly vehicle-dependent society, it is important to explore the historical record of vehicle-occupant deaths to see if the National Weather Service guidance is appropriate. The objective of this paper is to investigate the number, distribution, and broad spatial and temporal trends associated with vehicle-occupant deaths that have occurred as a result of tornadoes, and to define the proportion of tornado-induced deaths that have occurred in vehicles.

There were 15,047 deaths caused by tornadoes from 1900 through 1998. Of those, 5685 occurred at a defined site, and 270 were known to have occurred in vehicles. The number of vehicle-occupant deaths, as a proportion of all site-known, tornado-induced deaths, was constant from 1959–1979, but decreased significantly between 1980–1998. The number of deaths was related to several influencing factors. Linear regressions and correlations were employed to determine the degree of relationship between the number of deaths and several explanatory factors. While population, number of vehicle registrations, and number of tornadoes all seemed to influence the number of deaths to some degree, the most significant factor to influence the number of deaths appeared to be vehicle safety features. Most vehicle-occupant deaths occurred during rare F4 tornadoes, when vehicles where thrown from roadways. Regionally, the Great Plains had the highest number of vehicle-occupant deaths from tornadoes.     

Disaster devastation of US communities: long-term demographic consequences

This paper describes demographic changes resulting from devastating natural disasters in which at least half of the community's structures suffered major damage or total destruction. Considering 92 US communities that suffered disasters (mainly from hurricanes, river flooding, and tornadoes) between 1992 and 2008, locations that were already experiencing declining populations before their disaster were most likely to experience large post-disaster population losses. Communities suffering severe flooding were most likely to lose over a third of their population. Population movement typically occurred regardless of whether the community formally relocated. Small communities were particularly at risk of losing population following destruction, particularly when they lacked schools. Communities with higher home vacancy rates before their devastation were significantly more likely to experience large population declines. Wealthier communities and those located nearer metropolitan cities were most likely to retain their populations following major destruction, yet overall pre-disaster home values and median incomes in the communities were well below national averages. Race and Hispanic population were not significantly related to post-disaster population change in the overall study.     

A comparison of employment growth and stability before and after the Fort Worth tornado

This study examined the time series pattern of employment growth and stability in Fort Worth, Texas taking into account the March 28, 2000 tornado. The tornado is treated econometrically as an intervention and both the mean and conditional variance of employment growth were estimated. Overall, this regional labor market experienced a decline in the employment growth rate following the tornado. Among the sectors that exhibited differences in employment dynamics between the pre- and post-tornado periods, the mining sector experienced a significant increase in employment growth following the tornado while the service andwholesale, retail trade sectors experienced significant declines in employment growth in the post-tornado period. The manufacturing, service, and wholesale, retail trade sectors were characterized by greater stability (i.e., a lower level of employment growth volatility) in the post-tornado period than in the pre-tornado period. Interestingly, in several sectors, no differences in the time series dynamics of employment growth were detected between the pre- and post-tornado periods. These sectors included construction, finance, insurance, real estate, government, and transportation and public utilities.     

Earthquake mortality in Pakistan

A strong earthquake, measuring 7.6 on the Richter scale, hit northern Pakistan on 8 October 2005, causing massive destruction, including an official death toll of 73,276. Four cross-sectional surveys were performed in late 2005 to assess mortality before the event, on the day, and subsequently. Two surveys were community-based and two were situated in camps for internally displaced persons. Crude mortality rates were low in the 3.5 months preceding the earthquake (less than 0.1 deaths per 10,000 per day) and slightly higher in the six-to-eight weeks after the earthquake (ranging from 0.10–0.43 per 10,000 per day). On 8 October 2005, approximately two per cent of the population in one community survey died and around five per cent in the other three surveys. Children less than five years and adults more than or equal to 50 years tended to have a higher risk of mortality on the day of the disaster. These results corroborate the high mortality caused by the earthquake.     

Epidemiology of tornado destruction in rural northern Bangladesh: risk factors for death and injury

The epidemiology of tornado-related disasters in the developing world is poorly understood. An August 2005 post-tornado cohort study in rural Bangladesh identified elevated levels of death and injury among the elderly (≥ 60 years of age) (adjusted odds ratio (AOR) = 8.9 (95 per cent confidence interval (CI): 3.9-20.2) and AOR = 1.6 (95 per cent CI: 1.4-1.8), respectively), as compared to 15-24 year-olds, and among those outdoors versus indoors during the tornado (AOR = 10.4 (95 per cent CI: 5.5-19.9) and AOR = 6.6 (95 per cent CI: 5.8-7.5), respectively). Females were 1.24 times (95 per cent CI: 1.15-1.33) more likely to be injured than males. Elevated risk of injury was significantly associated with structural damage to the house and tin construction materials. Seeking treatment was protective against death among the injured, odds ratio = 0.08 (95 per cent CI: 0.03-0.21). Further research is needed to develop injury prevention strategies and to address disparities in risk between age groups and between men and women.     

四川泥石流灾害与降雨关系的初步探讨

2003年，四川共发生了8次泥石流灾害，造成了1130余人死亡和失踪，给地方经济带来了巨大的损失，是近年来灾害最为严重的一年。结合天气形势分析结果和收集的降水资料对8次泥石流灾害进行了分析，得出了泥石流灾害的发生大都伴有暴雨天气过程；暴发泥石流地区历年的降雨资料，说明这些区域在泥石流发生的当月，降雨量比历年普遍偏多。针对降雨对泥石流的激发作用和临界雨量问题，探索了四川泥石流灾害的发生规律，及相应预测预报和防灾决策。     

Residents' preparedness and response to the Kalamazoo Tornado

A survey was conducted of individuals residing directly in the path of the tornado that hit Kalamazoo, Michigan, on 13th May 1980. The residents' tornado preparedness and response were examined in an effort to evaluate the city's emergency warning system. The system was adequate for people on the east side of the city and lacking for west side residents. Other factors pertaining to the storm event and human response were also evaluated.     

Hurricane Katrina‐linked environmental injustice: race,class, and place differentials in attitudes

Claims of environmental injustice, human neglect, and racism dominated the popular and academic literature after Hurricane Katrina struck the United States in August 2005. A systematic analysis of environmental injustice from the perspective of the survivors remains scanty or nonexistent. This paper presents, therefore, a systematic empirical analysis of the key determinants of Katrina‐induced environmental injustice attitudes among survivors in severely affected parishes (counties) in Louisiana and Mississippi three years into the recovery process. Statistical models based on a random sample of survivors were estimated, with the results revealing significant predictors such as age, children in household under 18, education, homeownership, and race. The results further indicate that African‐Americans were more likely to perceive environmental injustice following Katrina than their white counterparts. Indeed, the investigation reveals that there are substantial racial gaps in measures of environmental injustice. The theoretical, methodological, and applied policy implications of these findings are discussed.     

Individual relocation decisions after tornadoes: a multi‐level analysis

This study examines how multi‐level factors affected individuals' relocation decisions after EF4 and EF5 (Enhanced Fujita Tornado Intensity Scale) tornadoes struck the United States in 2013. A telephone survey was conducted with 536 respondents, including oversampled older adults, one year after these two disaster events. Respondents' addresses were used to associate individual information with block group‐level variables recorded by the American Community Survey. Logistic regression revealed that residential damage and homeownership are important predictors of relocation. There was also significant interaction between these two variables, indicating less difference between homeowners and renters at higher damage levels. Homeownership diminished the likelihood of relocation among younger respondents. Random effects logistic regression found that the percentage of homeownership and of higher income households in the community buffered the effect of damage on relocation; the percentage of older adults reduced the likelihood of this group relocating. The findings are assessed from the standpoint of age difference, policy implications, and social capital and vulnerability.     

The 2004 tsunami and mental health in Thailand: a longitudinal analysis of one‐and two‐year post‐disaster data

Some 280,000 people died in the Indian Ocean tsunami on 26 December 2004. This cohort study examined its impact on mental health one and two years later. It did so by investigating the association between six consequent variables (personal injury, loss of home, loss of business, death of a family member, injury to a family member, or loss of a family member's business) and mental health, as measured by the 36‐item Short Form Health Survey (SF‐36), among residents in four provinces of Thailand. One year later, participants who suffered a personal injury, the loss of a business, or the loss of a family member reported poorer mental health than those who were unaffected. Two years later, participants who experienced the loss of a family member reported poorer mental health than those who were unaffected. This research shows that such a disaster may have long‐lasting ramifications for mental health, and that diverse losses may influence mental health differently.     

Substance use and functional impairment among adolescents directly exposed to the 2001 World Trade Center attacks

The relationship between exposure to the World Trade Center (WTC) attacks, increased substance use, functional impairment and mental health service use, controlling for depression and post-traumatic stress disorder, was assessed through an in-school survey of directly exposed students (N = 1040) attending the five middle and five high schools nearest the WTC. The survey was conducted 18 months after the attacks. Students with one WTC exposure risk factor had a five-fold increase in substance use, while those with three or more exposure risks had a nearly 19-fold increase. Increased substance use was associated with impaired school work, school behaviour and grades. Students reporting increased substance use were nearly twice as likely to want help but were no more likely than asymptomatic students to receive services. Adolescents reporting increased substance use, without co-morbidity, were less likely to receive psychological services than others. Attention to the needs of substance-using adolescents exposed to disaster is needed.     

2019年辽宁开原龙卷风观测事实分析

利用加密自动站、FY-4A卫星及多普勒雷达等观测资料,对2019年7月3日辽宁开原突发龙卷天气进行分析.结果表明:在冷涡减弱阶段,中纬度冷空气活动频繁,冷涡底部500 hPa与850 hPa的短波槽垂直分布,利于辽宁北部对流不稳定加强.FY-4A可见光云图显示,开原龙卷生消迅速,有明显的上冲云顶.雷达反射率因子特征是,...