Flash Flood Risks and Warning Decisions: A Mental Models Study of Forecasters,Public Officials,and Media Broadcasters in Boulder,Colorado

Timely warning communication and decision making are critical for reducing harm from flash flooding. To help understand and improve extreme weather risk communication and management, this study uses a mental models research approach to investigate the flash flood warning system and its risk decision context. Data were collected in the Boulder, Colorado area from mental models interviews with forecasters, public officials, and media broadcasters, who each make important interacting decisions in the warning system, and from a group modeling session with forecasters. Analysis of the data informed development of a decision‐focused model of the flash flood warning system that integrates the professionals’ perspectives. Comparative analysis of individual and group data with this model characterizes how these professionals conceptualize flash flood risks and associated uncertainty; create and disseminate flash flood warning information; and perceive how warning information is (and should be) used in their own and others’ decisions. The analysis indicates that warning system functioning would benefit from professionals developing a clearer, shared understanding of flash flood risks and the warning system, across their areas of expertise and job roles. Given the challenges in risk communication and decision making for complex, rapidly evolving hazards such as flash floods, another priority is development of improved warning content to help members of the public protect themselves when needed. Also important is professional communication with members of the public about allocation of responsibilities for managing flash flood risks, as well as improved system‐wide management of uncertainty in decisions.     

“Know What to Do If You Encounter a Flash Flood”: Mental Models Analysis for Improving Flash Flood Risk Communication and Public Decision Making

Understanding how people view flash flood risks can help improve risk communication, ultimately improving outcomes. This article analyzes data from 26 mental models interviews about flash floods with members of the public in Boulder, Colorado, to understand their perspectives on flash flood risks and mitigation. The analysis includes a comparison between public and professional perspectives by referencing a companion mental models study of Boulder‐area professionals. A mental models approach can help to diagnose what people already know about flash flood risks and responses, as well as any critical gaps in their knowledge that might be addressed through improved risk communication. A few public interviewees mentioned most of the key concepts discussed by professionals as important for flash flood warning decision making. However, most interviewees exhibited some incomplete understandings and misconceptions about aspects of flash flood development and exposure, effects, or mitigation that may lead to ineffective warning decisions when a flash flood threatens. These include important misunderstandings about the rapid evolution of flash floods, the speed of water in flash floods, the locations and times that pose the greatest flash flood risk in Boulder, the value of situational awareness and environmental cues, and the most appropriate responses when a flash flood threatens. The findings point to recommendations for ways to improve risk communication, over the long term and when an event threatens, to help people quickly recognize and understand threats, obtain needed information, and make informed decisions in complex, rapidly evolving extreme weather events such as flash floods.     

Flash Flood Awareness in Southwest Virginia

Flash floods are one of the most dangerous weather-related natural disasters in the world. These events develop less than six hours after a rainfall event and create hazardous situations for people and extensive damage to property. It is critical for flash flood conditions to be warned of in a timely manner to minimize impacts. There is currently a knowledge gap between flood experts and the general public about the level of perceived risk that the latter has toward the powerful flood waters and how events should be warned of, which affects the communication capabilities and efficiency of the warning process. Prior research has addressed risk perception of natural disasters, but there is little emphasis on flash floods within flood-prone regions of the United States. This research utilizes an online survey of 300 respondents to determine the current state of flash flood awareness and preparation in southwest Virginia. Analysis of trends involved the use of chi-squared tests (chi2) and simple frequency and percentage calculations. Results reveal that a knowledge base of flash floods does exist, but is not advanced enough for proper awareness. Young adults have a lower understanding and are not as concerned about flood impacts. Increased exposure and perceived risk play a key role in shaping the way a person approaches flash floods. People do monitor flood events, but they are unaware of essential guidance and communication mechanisms. Finally, results suggest that the current method of warning about flash floods is not provided at an appropriate level of detail for effective communication.     

How Do Disaster Characteristics Influence Risk Perception?

The main purpose of this study is to examine how risk perception is influenced by the type of disaster (flood or landslide) and victim characteristics. The data reported here are based on the National Risk Perception Survey (NRPS) that was administered for the victims and the general public in Taiwan in 2004. In that year, many towns in Taiwan were seriously affected by floods and landslides, resulting in huge economic losses and fatalities. The primary findings are: (1) the victims and the general public are concerned about the different potential hazards that might affect their residential area, (2) the negative associations between the sense of controllability and the perceived impact is high for landslide victims, but not for flood victims, and (3) disaster type, gender, and previously experienced disasters are good predictors of victims' attitudes toward natural disasters.     

Mortality Patterns of Hydro‐Geomorphologic Disasters

Social impacts caused by floods and landslides in Portugal in the period of 1865–2010 are gathered in the DISASTER database. This database contains 1,902 hydro‐geomorphologic cases that caused 1,248 fatalities (81% and 19% associated with floods and landslides, respectively). The use of the DISASTER database allowed for: (i) the analysis of the frequency and the temporal evolution of fatal floods and landslides; (ii) the analysis of the spatio‐temporal distribution of fatalities; (iii) the identification of the most deadly flood and landside types; (iv) the verification of gender tendencies in mortalities; and (v) the evaluation of individual and societal risk. The highest number of flood and landslide cases and related mortalities occurred in the period of 1935–1969. After this period, the number of flood and landslide mortalities decreased, although landslide fatalities remained higher than those registered in the period of 1865–1934. The occurrence of flood fatalities was widespread in the country, with an important cluster in the Lisbon region and in the Tagus valley, while fatalities caused by landslides mainly occurred in the north of the Tagus valley. Flash floods caused the majority of fatalities associated with floods, while falls and flows were responsible for the highest number of fatalities associated with landslides. Males were found to have the highest frequency of fatalities. In the case of floods, the majority of fatalities were found both outdoors and inside of buildings in rural areas while fatalities inside buildings were dominant in landslide cases, mostly in rural areas.     

The Unintended Effects of Risk‐Refuting Information on Anxiety

Researchers in the field of risk perception have been asking why people are more worried about risk today than in years past. This article explores one possible answer to this question, associative anxiety. The affect heuristic and the mental network models suggest that anxiety triggered by information regarding a particular risk can spread to other risks of the same category. Research to date, however, has not examined how information refuting the particular risk can also be generalized across other risks. The article presents two experimental studies addressing this issue. Study 1 showed that when participants were presented with information based on a real train collision, they experienced increased anxiety not only about train collisions but also about public transportation in general. In contrast, those who were informed about the train collision case as well as the preventative measures implemented after the accident experienced decreased anxiety about train collisions but not about public transportation more generally. Study 2 measured the changes in participant anxiety about a genetically modified organism (GMO) and compared the influence of information about either the existence or nonexistence of its risk. Similar to Study 1, associative anxiety rippled through the risk category. The results also suggest that the follow‐up information refuting the GMO risk reduced the anxiety toward the hazard drastically, but did not fully alleviate the anxiety toward other hazards in the category. The implications and the limitations of these studies are also discussed.     

Hot Potato: Expert-Consumer Differences in the Perception of a Second-Generation Novel Food

Novel foods have been the object of intense public debate in recent years. Despite widespread efforts to communicate the outcomes of risk assessments to consumers, public confidence in risk management has been low. Social scientists have identified various reasons for this, including a disagreement between technical experts and consumers over the nature of the hazards on which risk assessments should focus. The aim of this study was to identify and compare the ways in which experts and consumers understand the benefits and risks associated with a genetically modified example crop. Two qualitative studies were conducted. In Study 1, mental models were elicited from 24 experts by means of a three-wave Delphi procedure. In Study 2, mental models were elicited from 25 consumers by means of in-depth interviews. As expected, the expert mental models were focused on the types of hazards that can realistically be addressed under current regulatory frameworks, whereas the consumers were often more concerned about issues outside the scope of current legislation. Moreover, the experts tended to define risk and benefit in terms of detailed chains of cause-effect relationships between variables for which clear definitions and measurement rules exist. The concepts the consumers used when reasoning about biological processes were very abstract, suggesting that the participants had, at most, a holistic understanding. In line with this, issues of uncertainty played a prominent role for the consumers.     

Awareness of Bad News, Environmental Attitudes, and Subjective Estimates of Coastal Pollution

Questionnaires distributed to 154 holiday-makers on beaches in Southwest England assessed awareness of local hazards or incidents associated with either the electricity supply industry or the water and sewage industry and examined the relationship between awareness and evaluations of the industry, current and future levels of pollution on the beach in question, and general levels of concern about environmental pollution. With respect to electricity, those respondents who were more aware of reports claiming a higher incidence of childhood leukemia in the vicinity of a nearby nuclear plant evaluated the electricity industry as less competent or trustworthy, showed higher levels of environmental concern, and were more pessimistic in their estimates of present and future levels of specific pollutants on their beach. With respect to the water industry, similar effects were associated with greater awareness of an accident at a water treatment plant and agricultural pollution of a nearby estuary. These findings are interpreted as suggesting a cyclical relationship between risk awareness and concern. On the one hand, reports about environmental hazards may lead to generalized concern across specific contexts; on the other hand, greater levels of concern may sensitize individuals to such reports.     

Public Perceptions of Everyday Food Hazards: A Psychometric Study

In this paper, we discuss the conduct and results of a study aimed at eliciting public perceptions of food-related hazards. This study employs the psychometric approach of Paul Slovic and colleagues and aims to extend the recent work of Sparks and Shepherd⁽¹⁾ on defining the primary dimensions of food-related risk perceptions. The study surveyed a nationally representative sample of the general public (respondents = 293; adjusted response rate = 30.1%). Respondents provided ratings on subsets of 22 potential food hazards (e.g., food irradiation and presence of listeria) on a total of 19 risk characteristics (e.g., "perceived severity of risk" and "adequacy of governmental regulations"). In spite of the use of a number of new characteristics and food hazards, Principal Components Analysis revealed a broadly similar factor structure to that obtained by Sparks and Shepherd,⁽¹⁾ suggesting the generalizability of the key dimensions (concerning the severity and awareness of hazards). Interestingly, the positioning in the factor space of potential hazards about which little was generally known (e.g., campylobacter) as being serious and in need of regulation, may suggest a possible "starting position" in the perception of new hazards that have not previously been the subject of risk communications.     

Risk Perceptions and Trust Following the 2010 and 2011 Icelandic Volcanic Ash Crises

Eruptions at the Icelandic volcanoes of Eyjafjallajökull (2010) and Grimsvötn (2011) produced plumes of ash posing hazards to air traffic over northern Europe. In imposing restrictions on air traffic, regulators needed to balance the dangers of accidents or aircraft damage against the cost and inconvenience to travelers and industry. Two surveys examined how members of the public viewed the necessity of the imposed restrictions and their trust in different agencies as estimators of the level of risk. Study 1 was conducted with 213 British citizens (112 males, 101 females), who completed questionnaires while waiting for flights at London City Airport during May 2012. Study 2 involved an online survey of 301 Icelandic citizens (172 males, 127 females, 2 undeclared gender) during April 2012. In both samples, there was general support for the air traffic restrictions, especially among those who gave higher estimates of the likelihood of an air accident or mishap having otherwise happened. However, in both countries, the (minority of) respondents who had personally experienced travel disruption were less convinced that these restrictions were all necessary. Scientists, the International Civil Aviation Organization, and (in Iceland) the Icelandic Department of Civil Protection were all highly trusted, and seen as erring on the side of caution in their risk estimates. Airlines were seen as more likely to underestimate any risk. We conclude that perceptions of the balance between risk and caution in judgments under uncertainty are influenced by one's own motives and those attributed to others.     

Risk Perception,Experience, and Objective Risk: A Cross‐National Study with European Emergency Survivors

Understanding public risk perceptions and their underlying processes is important in order to learn more about the way people interpret and respond to hazardous emergency events. Direct experience with an involuntary hazard has been found to heighten the perceived risk of experiencing the same hazard and its consequences in the future, but it remains unclear if cross‐over effects are possible (i.e., experience with one hazard influencing perceived risk for other hazards also). Furthermore, the impact of objective risk and country of residence on perceived risk is not well understood. As part of the BeSeCu (Behavior, Security, and Culture) Project, a sample of 1,045 survivors of emergencies from seven European countries (i.e., Germany, the Czech Republic, Poland, Sweden, Spain, Turkey, and Italy) was drawn. Results revealed heightened perceived risk for emergency events (i.e., domestic and public fires, earthquakes, floods, and terrorist attacks) when the event had been experienced previously plus some evidence of cross‐over effects, although these effects were not so strong. The largest country differences in perceived risk were observed for earthquakes, but this effect was significantly reduced by taking into account the objective earthquake risk. For fires, floods, terrorist attacks, and traffic accidents, only small country differences in perceived risk were found. Further studies including a larger number of countries are welcomed.     

The Use of Mental Models in Chemical Risk Protection: Developing a Generic Workplace Methodology

We adopted a comparative approach to evaluate and extend a generic methodology to analyze the different sets of beliefs held about chemical hazards in the workplace. Our study mapped existing knowledge structures about the risks associated with the use of perchloroethylene and rosin-based solder flux in differing workplaces. "Influence diagrams" were used to represent beliefs held by chemical experts; "user models" were developed from data elicited from open-ended interviews with the workplace users of the chemicals. The juxtaposition of expert and user understandings of chemical risks enabled us to identify knowledge gaps and misunderstandings and to reinforce appropriate sets of safety beliefs and behavior relevant to chemical risk communications. By designing safety information to be more relevant to the workplace context of users, we believe that employers and employees may gain improved knowledge about chemical hazards in the workplace, such that better chemical risk management, self-protection, and informed decision making develop over time.     

Attitudes and Risk Perceptions of Stakeholders in a Nuclear Waste Siting Issue

Stakeholders are often regarded as a critically important group in such issues as the siting of nuclear facilities. In this article, stakeholders were identified on the basis of self-reported activities with regard to a nuclear waste siting issue under debate in four communities. Data were obtained in an extensive mailed survey from a total of 2,548 respondents, approximately an equal number from each community. The overall response rate was 43.9%. Some of the results and telephone interviews with a sample of the nonrespondents indicated that the data are reasonably representative of the respective populations. Stakeholder activities were measured by 20 questions and combined with an index of stakeholder activity level, dichotomized at the 90th percentile. Stakeholders were found to have a higher level of education than others, but otherwise they did not differ in demographics. They did not tend to see risks in general as high, but were quite interested and involved in the nuclear waste siting issue. The stakeholder activity level correlated with risk perception and attitudes in the waste siting issue, but with different signs for those who were for and those who were opposed: stakeholders of both types had more extreme views than others, but in different directions. In addition, stakeholder opponents were much more likely to strongly espouse extreme statements regarding the project than were supporters who also were stakeholders. Implications for risk management and communication are discussed.     

Fairness and nanotechnology concern

Research suggests that fairness perceptions matter to people who are asked to evaluate the acceptability of risks or risk management. Two separate national random surveys (n = 305 and n = 529) addressed Americans’ concerns about and acceptance of nanotechnology risk management in the context of the degree to which they view scientists and risk managers as fair. The first survey investigated general views about scientists across four proposed dimensions of fairness (distributional, procedural, interpersonal, and informational). The results show that respondents who believe that the outcomes of scientific research tend to result in unequal benefits (distributional fairness) and that the procedures meant to protect the public from scientific research are biased (procedural fairness) were more concerned about nanotechnology. Believing scientists would treat them with respect (interpersonal fairness) and ensure access to information (informational fairness) were not significant predictors of concern. The second study also looked at these four dimensions of fairness but focused on perceptions of risk managers working for government, universities, and major companies. In addition to concern, it also examined acceptance of nanotechnology risk management. Study 2 results were similar to those of study 1 for concern; however, only perceived informational fairness consistently predicted acceptance of nanotechnology risk management. Overall, the study points to the value of considering fairness perceptions in the study of public perceptions of nanotechnology.     

Information Technology Risks as Seen by the Public

Risks related to information technology (IT) are becoming a focus of concern in current risk debates. The use of IT is rapidly spreading in the population, as is access to computers in general. The present article reviews the literature on IT use (especially electronic mail and various Internet applications) and the related risks. In addition, the results from a survey about IT use and risk perception, given to a random sample of the Swedish population, are reported. In general, participants were quite positive to IT and were, to some extent, aware of the related risks. However, risks of IT were mostly seen as pertinent to other people, a finding in contrast with other results on perceived technology hazards. The attitude toward the use of IT was strongly related to general attitude toward computers, and less clearly to risk perception. Only a small percentage of the respondents reported having had negative experiences with IT hazards such as Internet addiction, depression, and social isolation. When extrapolated to the general population, however, these small percentages amount to large groups in the population that have been negatively affected by IT use.     

Energy Choices and Risk Beliefs: Is It Just Global Warming and Fear of a Nuclear Power Plant Accident?

A survey of 3,200 U.S. residents focused on two issues associated with the use of nuclear and coal fuels to produce electrical energy. The first was the association between risk beliefs and preferences for coal and nuclear energy. As expected, concern about nuclear power plant accidents led to decreased support for nuclear power, and those who believed that coal causes global warming preferred less coal use. Yet other risk beliefs about the coal and nuclear energy fuel cycles were stronger or equal correlates of public preferences. The second issue is the existence of what we call acknowledged risk takers, respondents who favored increased reliance on nuclear energy, although also noting that there could be a serious nuclear plant accident, and those who favored greater coal use, despite acknowledging a link to global warming. The pro‐nuclear group disproportionately was affluent educated white males, and the pro‐coal group was relatively poor less educated African‐American and Latino females. Yet both shared four similarities: older age, trust in management, belief that the energy facilities help the local economy, and individualistic personal values. These findings show that there is no single public with regard to energy preferences and risk beliefs. Rather, there are multiple populations with different viewpoints that surely would benefit by hearing a clear and comprehensive national energy life cycle policy from the national government.     

Gender Differences in Risk Perception: Effects Differ in Stressed vs. Non-Stressed Environments

Contrary to previous reports that women are more concerned about environmental risks than men, we hypothesized that men and women residing in neighborhoods stressed by multiple hazards would demonstrate similar concerns about local environmental conditions. Analysis of a national data base and an aggregate of ten local data bases found greater female than male concern about local technological, behavioral, and land use hazards in good neighborhoods, but, as expected, not in stressed ones. We urge analysts to conduct more studies in stressed neighborhoods in order to better understand the perspective of those who live with environmental risks.     

Efficacy Foundations for Risk Communication: How People Think About Reducing the Risks of Climate Change

Believing action to reduce the risks of climate change is both possible (self‐efficacy) and effective (response efficacy) is essential to motivate and sustain risk mitigation efforts, according to current risk communication theory. Although the public recognizes the dangers of climate change, and is deluged with lists of possible mitigative actions, little is known about public efficacy beliefs in the context of climate change. Prior efficacy studies rely on conflicting constructs and measures of efficacy, and links between efficacy and risk management actions are muddled. As a result, much remains to learn about how laypersons think about the ease and effectiveness of potential mitigative actions. To bring clarity and inform risk communication and management efforts, we investigate how people think about efficacy in the context of climate change risk management by analyzing unprompted and prompted beliefs from two national surveys (N = 405, N = 1,820). In general, respondents distinguish little between effective and ineffective climate strategies. While many respondents appreciate that reducing fossil fuel use is an effective risk mitigation strategy, overall assessments reflect persistent misconceptions about climate change causes, and uncertainties about the effectiveness of risk mitigation strategies. Our findings suggest targeting climate change risk communication and management strategies to (1) address gaps in people's existing mental models of climate action, (2) leverage existing public understanding of both potentially effective mitigation strategies and the collective action dilemma at the heart of climate change action, and (3) take into account ideologically driven reactions to behavior change and government action framed as climate action.     

Powerline Frequency Electric and Magnetic Fields: A Pilot Study of Risk Perception

The perception of the potential risk arising from human exposure to 50/60 Hz electric and magnetic fields was studied with a quasi-random sample of 116 well-educated, opinion leaders using the risk perception framework previously developed by Slovic, Fischhoff, and Lichtenstein. These individuals rated exposure to fields from transmission lines and electric blankets on a variety of scales that have been found useful in characterizing people's risk attitudes and perceptions. These judgments allowed us to conjecture about the likely desire for regulation of these potential hazards and the likely response to a publicized problem (e.g., an accident or ominous research finding) involving these two sources of exposure. Various forms of detailed information about 50/60 Hz fields were supplied to respondents. The provision of information produced modest, but statistically significant, changes in perceptions in the direction of greater concern about the risks. In response to questions of public policy, participants desired modest regulatory control of field exposure from transmission lines and little or no control of field exposure from appliances like electric blankets.     

Egyptian Farmers' Attitudes and Behaviors Regarding Agricultural Pesticides: Implications for Pesticide Risk Communication

The need to boost pre- and postharvest agricultural productivity serves as a powerful driving force for developing countries to promote the use of agricultural pesticides. Pesticides are, however, "poisons by design" and poisonings resulting from unsafe use of these chemicals are the most prevalent and serious occupational hazards faced by agricultural workers in developing countries. This article provides the results of a study designed to investigate the extent of unsafe use of pesticides by farmers in one of the largest agricultural areas in Egypt, the farmers' knowledge about pesticides, and their preferred sources of receiving risk information on pesticides. The results of this study show a high level of unsafe use of pesticides and inappropriate methods of disposal of empty pesticide containers. Also, knowledge about pesticides is scant. Notwithstanding that more than half of the farmers obtain regular drinking water from wells, most of the respondents were "not sure" as to whether or not pesticides may contaminate groundwater. The low level of knowledge about pesticides can be attributed to relatively low levels of education and that almost all the respondents have never participated in a pesticide education program. This article concludes with a recommendation for pesticide and pesticide use education programs, especially through "ministry officials" who most of the respondents seem to trust regarding receiving pesticide information.