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Robert Prestley
and
Rebecca E. Morss

Abstract

Common disaster-phase models provide a useful heuristic for understanding how disasters evolve, but they do not adequately characterize the transitions between phases, such as the forecast and warning phase of predictable disasters. In this study, we use tweets posted by professional sources of meteorological information in Florida during Hurricane Irma (2017) to understand how visual risk communication evolves during this transition. We identify four subphases of the forecast and warning phase: the hypothetical threat, actualized threat, looming threat, and impact subphases. Each subphase is denoted by changes in the kinds of visual risk information disseminated by professional sources and retransmitted by the public, which are often driven by new information provided by the U.S. National Weather Service. In addition, we use regression analysis to understand the impact of tweet timing, content, risk visualization and other factors on tweet retransmission across Irma’s forecast and warning phase. We find that cone, satellite, and spaghetti-plot image types are retweeted more, while watch/warning imagery is retweeted less. In addition, manually generated tweets are retweeted more than automated tweets. These results highlight several information needs to incorporate into the current NWS hurricane forecast visualization suite, such as uncertainty and hazard-specific information at longer lead times, and the importance of investigating the effectiveness of different social media posting strategies. Our results also demonstrate the roles and responsibilities that professional sources engage in during these subphases, which builds understanding of disasters by contextualizing the subphases along the transition from long-term preparedness to postevent response and recovery.

Significance Statement

Visual information is an important tool for communicating about evolving tropical cyclone threats. In this study, we investigate the kinds of visualizations posted by professional weather communicators on Twitter during Hurricane Irma (2017) to understand how visual information shifts over time and whether different visuals are more retweeted. We find that visual information shifts substantially in the days before Irma’s impacts, and these shifts are often driven by changes in Irma’s strength or forecast track. Our results show that cone, satellite, and spaghetti-plot visualizations are retweeted more frequently, while watch/warning imagery is retweeted less. These results help us to understand how visual information evolves during predictable disasters, and they suggest ways that visual communication can be improved.

Restricted access
O. V. Wilhelmi
,
B. C. Chamberlain
,
R. E. Morss
,
J. L. Demuth
,
H. D. Walpole
,
J. Boehnert
,
J. M. Gambill
,
H. Lazrus
, and
J. G. Dobson

Abstract

Geovisualizations play a central role in communicating hurricane storm surge risks to the public by connecting information about the hazard to a place. Meanwhile, people connect to places through meaning, functions, and emotional bond, known as a sense of place. The mixed-method approach presented in this paper focuses on the intersection of sense of place, geovisualization, and risk communication. We explored place meaning, scale of place, and place attachment in the coastal communities in Georgia and South Carolina. We conducted cognitive mapping focus groups and developed a series of geovisualizations of storm surge risk with varying representations of place. We then investigated people’s ability to connect visual storm surge information to a place and understand their risk by testing these geovisualizations in a large population survey (n = 1442). We found that a 2D regional-scale map displayed together with a 3D abstract representation of a neighborhood was the most helpful in enabling people to relate to a place, quickly make sense of the information, and understand the risk. Our results showed that while the geovisualizations of storm surge risk can be effective generally, they were less effective in several important and vulnerable groups. We found substantial impacts of race, income, map-reading ability, place attachment, and scale of place on how people connected the storm surge risk shown in the visual to a place. These findings have implications for future research and for considering the way weather forecasters and emergency managers communicate storm surge information with diverse audiences using geovisualizations.

Significance Statement

Weather forecasters and emergency managers often use geovisualizations to communicate hurricane storm surge risks and threats to the public. Despite the important role that geovisualizations play, few studies have empirically investigated their effectiveness in hazardous weather risk communication. With the overarching goal of understanding how geovisualizations enable coastal residents to understand and respond to risk, we use an interdisciplinary approach to create new knowledge about the effectiveness of geovisualizations in storm surge risk communication. Our results show substantial impacts of sociodemographic factors across many of the measures that enable people to connect to a place through visualizations. These findings have implications for communicating geospatially varying risk to diverse audiences.

Open access
Rakesh Gomaji Nannewar
,
Tejal Kanitkar
, and
R. Srikanth

Abstract

Providing knowledge inputs to farmers is critical to reduce their vulnerability and enhance resilience against climate change. In developing countries such as India, where small holdings and rain-fed agriculture are predominant, knowledge inputs become even more critical. The India Meteorological Department has provided integrated agrometeorological advisory services (AAS) to farmers since 2008. In this paper, we estimate the scale of access to AAS and its impact on crop yields in 1000 households across 10 villages in two agroclimatic zones in India. We find evidence suggesting that access to AAS can have a significant impact on crop yields in the kharif (June–September) season, whereas other inputs are more important in the case of rabi (winter) crops. Specifically, the yields of pigeon pea, soybean, and pearl millet are higher by 233, 98, and 318 kg ha−1, respectively, for AAS beneficiaries. For the entire study area, this translates to a value addition of $9.66 million for these three crops in one season. Our results show that AAS can be an important contributor to meeting the developmental goals of enhancing food security in dry-land agriculture and building resilience against climate change.

Significance Statement

In the era of climate change, with rapidly increasing weather and climatic variability, protecting the incomes of small farmers and ensuring they have the capacity to adapt and build resilience to the growing impacts of climate change is an urgent necessity. We have studied the impact of knowledge services such as the agrometeorological advisory services of the India Meteorological Department on crop yields for major crops in dry agroclimatic zones in India. The study shows that large public programs like the agrometeorological advisory services that bring science to people in meaningful ways can contribute significantly to meeting developmental goals and building resilience against climate change.

Restricted access
Taylor A. DeWinter-Maciag
and
Renee A. McPherson

Abstract

Although decision-making in response to tornado warnings is well researched, most studies do not examine whether individual responses to these warnings vary across different geographical locations and demographic groups. This gap is addressed by using data from a decision experiment that places participants virtually in a simulated tornado warning and asks them to minimize the costs of their decisions. The authors examine the following: 1) what demographic attributes may contribute to choices to minimize costs to protect assets at a specific location in a tornado warning, 2) whether there is a spatial component to how these attributes influence decision-making, and 3) if there are specific U.S. regions where individuals do not make protective decisions that minimize their overall cost. Multilevel regression analysis and poststratification are applied to data from the simulated decision experiment to estimate which demographic attributes and National Weather Service County Warning Areas are most associated with the costliest protective decisions. The results are then analyzed using spatial autocorrelation to identify spatial patterns. Results indicate that sex, race, and ethnicity are important factors that influence protection decisions. Findings also show that people across the southern portions of the United States tend to make more costly protective decisions, as defined in this work.

Significance Statement

Tornadoes, although rare, threaten both life and property. Studies have shown that certain demographic groups are more negatively impacted by disasters than others and are at higher risk of severe weather hazards. We ask if there are demographic characteristics or geographic locations in common among people who are more prone to making protection decisions during tornado warnings to minimize economic costs. Results can help warning providers, such as the National Weather Service, direct resources and education to specific types of decision-makers or locations to improve sheltering decisions.

Open access
Mary Anne T. Clive
,
Emma E. H. Doyle
,
Sally H. Potter
,
Chris Noble
, and
David M. Johnston

Abstract

Multiday severe weather outlooks can inform planning beyond the hour-to-day windows of warnings and watches. Outlooks can be complex to visualize, as they represent large-scale weather phenomena overlapping across several days at varying levels of uncertainty. Here, we present the results of a survey (n = 417) that explores how visual variables affect comprehension, inferences, and intended decision-making in a hypothetical scenario with the New Zealand MetService Severe Weather Outlook. We propose that visualization of the time window, forecast area, icons, and uncertainty can influence perceptions and decision-making based on four key findings. First, composite-style outlooks that depict multiple days of weather on one map can lead to biased perceptions of the forecast. When responding to questions about a day for which participants accurately reported there was no severe weather forecast, those who viewed a composite outlook reported higher likelihoods of severe weather occurring, higher levels of concern about travel, and higher likelihoods of changing plans compared to those who viewed outlooks that showed weather for each day on a separate map, suggesting that they perceived the forecast to underrepresent the likelihood of severe weather on that day. Second, presenting uncertainty in an extrinsic way (e.g., “low”) can lead to more accurate estimates of likelihood than intrinsic formats (e.g., hue variation). Third, shaded forecast areas may lead to higher levels of confidence in the forecast than outlined forecast areas. Fourth, inclusion of weather icons can improve comprehension in some conditions. The results demonstrate how visualization can affect decision-making about severe weather and support several evidence-based considerations for effective design of long-term forecasts.

Significance Statement

Severe weather outlook forecasts can be hard to clearly communicate because they show multiple weather patterns across multiple days and regions with varying uncertainty. The purpose of this study is to explore how visual elements of outlook design affect the way that people understand this complex content. We had three separate groups respond to the same series of questions while viewing different modified versions of the MetService Severe Weather Outlook in Aotearoa New Zealand and compared their responses. We find that the way the outlooks’ time window, forecast area, icons, and uncertainty are visualized can influence how people understand outlooks and make inferences and decisions about severe weather. We discuss how these influences may impact communication and action and present several evidence-based considerations for effective outlook design.

Open access
Mahdi Zarei
,
Seyyed Hadi Hosseini
, and
Mahnaz Naemitabar

Abstract

The motivations of this research are the continuation and intensification of drought effects on various socioeconomic sectors and the observation of few studies and no coordinated efforts to provide a compatible framework for drought risk management in different economic sectors and population groups of the study region. Present research was carried out to assess the vulnerability and population exposed to drought in Khorasan Razavi Province. Meteorological datasets for the years 1950–2020; drought indices including self-calibrating Palmer (scPDSI), standardized precipitation (SPI), and standardized precipitation evapotranspiration (SPEI); population and livestock density indicators; agricultural lands; water stress; and socioeconomic and infrastructural factors have been used. Results indicate that dry and wet periods were estimated to be more intense by SPEI in all studied stations; also, a significant difference was observed between the results of the SPI and SPEI indices in determining the long dry and wet periods. The highest variation between the occurrence of dry and wet periods was estimated using SPEI, which could be related to seasonal fluctuations of temperature and computational evapotranspiration. Although no significant correlation was observed between used indices to identify the number of wet months, a significant positive correlation exists between the numbers of dry months estimated by those. Drought risk analysis demonstrated that the central and southern parts of the province are exposed to very severe drought while the northern and northeastern parts of the area are more inclined to severe drought. The highest class of drought exposure is observed in the southern, central, and eastern regions of the province, so they represent the high-risk category of drought.

Free access
Kelsey N. Ellis
,
Jennifer M. First
,
Stephen M. Strader
,
Nicholas S. Grondin
,
Daniel Burow
, and
Zachary Medley

Abstract

Simultaneous and overlapping tornadoes and flash floods are a meteorological hazard with complex societal implications as, when issued at the same time, tornado and flash flood warnings provide conflicting public safety advice. This work assessed potential tornado and flash flood (TORFF) events in a portion of the Southeast from an interdisciplinary perspective with a focus on the climatology, vulnerability, and public perceptions surrounding these hazards. Our results suggest that, in addition to the conflicting warning advice, TORFFs present a challenge to the public because they can occur at night or in cool seasons when they are least expected, though they are most common in spring. Also, the storms causing TORFFs are often not clearly organized, causing a forecast and communication challenge. The public responding to the tornado and flash flood warnings in our study area is more vulnerable to TORFFs than those in other areas and may lack vehicles and structures to respond safely to one or both hazard threats. Administered survey results suggest that many believe they know what protective actions to take in a TORFF, though they may not believe they are likely in their area. Those that believe they are likely are also more likely to feel prepared to respond. Many climatology and vulnerability characteristics vary between, and at times within, NWS county warning areas, highlighting the different communication and preparation needs across the region. Approximately a quarter of flash flood and tornado warnings overlap in the region for an average of 31 min. The frequency of TORFFs and their associated public safety challenges warrant continued investigation.

Significance Statement

The purpose of this work is to increase our understanding of overlapping tornado and flash flood events by studying them from a multidisciplinary perspective. We found that residents in the southeastern United States are especially vulnerable to overlapping tornado and flash floods. This vulnerability is heightened by the climatology of overlapping tornado and flash floods because they can occur when they are unexpected, for example, at night or in the winter, and the public perceptions of overlapping tornado and flash floods, which is that they may not be likely in their area. These findings are important because much of the Southeast includes a population vulnerable to overlapping tornado and flash floods who may be underestimating their risk, and therefore may be unprepared for an event that requires critical decision-making.

Free access
Michele K. Olson
,
Jeannette Sutton
, and
Nicholas Waugh

Abstract

Heat communication interventions are an essential way that public safety organizations can reduce extreme heat consequences for at-risk groups. Although the aim of these interventions is typically behavior change, these organizations commonly assume that providing information about heat risks, impacts, vulnerable populations, and protective actions will lead individuals to protect themselves. However, behavior change is a complex process whereby messages must be crafted in ways that increase their persuasive effects. To examine the extent to which key assumptions about behavior change are present in public safety organizations’ heat communication interventions, we examine 250 heat-related tweets sent by seven National Weather Service (NWS) weather forecast offices (WFOs) in 2021. We find that these NWS WFOs use technical language or “jargon” to communicate about heat risks and impacts. In addition, we find that information about vulnerable populations and protective actions is not presented in a way that conforms to theory on behavior change. Based on these results, we offer recommendations to increase the persuasiveness of NWS WFO communication interventions that encourage the public to protect themselves during extreme heat events.

Significance Statement

Heat is the leading cause of death among all weather-related hazards. How heat is communicated to the public can help mitigate heat-related morbidity and mortality. However, heat communication interventions are often developed with several embedded assumptions about behavior change that negatively impact their effectiveness. By examining how a key public safety organization communicates about heat on social media, and the extent to which these assumptions are present, we offer recommendations to increase the persuasiveness of NWS heat communication on social media.

Free access
Caily Schwartz
,
Tonya Haigh
,
Mark Svoboda
, and
Madeline Goebel

Abstract

Because flash drought is a relatively new phenomenon in drought research, defining the concept is critical for scientists and decision-makers. Having detrimental impacts on many sectors, it is important to have a consistent definition and understanding of flash drought, between experts and stakeholders, to provide early warning to the community. This study focuses on onset and progression of conditions and demonstrates the difference in flash drought identification for 15 events across six quantitative definitions of flash drought that use the U.S. Drought Monitor (USDM). Five flash drought events have been studied in the literature while 10 additional events have been perceived as flash drought by stakeholders. The results show that two of six definitions consistently capture the earliest onset of flash drought and include a large percent area in the identification. A qualitative analysis of management challenges and needs determined by stakeholders was completed using survey data. The results found that managing impacts and better communication and education were the top challenges and more data and enhanced and efficient communication as the top needs to better monitor, manage, and respond to flash droughts. The results demonstrate the need for assessing the characteristics of the definitions to enhance communication and monitoring strategies for large and small-scale flash droughts.

Significance Statement

The purpose of this study is to better understand how different numerical flash drought definitions characterize multiple flash drought events and how these definitions are useful in addressing the needs and challenges of stakeholders. This is important because definitions may capture different areas in flash droughts, which can impact how end users identify a flash drought. Further, this study uses events identified by the literature and by people familiar with drought monitoring. From these findings, definitions that capture flash drought earliest would help address the challenge of rapid onset and the need of quicker data. Further, definitions by sector would be beneficial to address the scale of impacts. This study identifies the importance of definitions for early warning systems.

Open access
Shari Fox
,
Alex Crawford
,
Michelle McCrystall
,
Julienne Stroeve
,
Jennifer Lukovich
,
Nicole Loeb
,
Jerry Natanine
, and
Mark Serreze

Abstract

Arctic communities are experienced with severe weather, but impacts can still be serious, particularly when the intensity or persistence of hazardous conditions is extreme. Such was the case for the community of Clyde River (Kangiqtugaapik), Nunavut, Canada, which experienced 33 blizzard days during winter 2021/22—likely the most at Clyde River since at least 1978/79. Blizzard conditions resulted from unusually frequent high winds rather than excessive snowfall. The most severe stretch included eight blizzard days over an 11-day period, with top wind gusts of 98 km h−1. Winds caused severe drifting, covering homes and blocking streets. Broken heavy equipment, including snow-clearing machines, compounded the impacts, leaving homes without essential services like water delivery and sewage pump-out for days. Residents reported the storms and resulting impacts as some of the worst in memory. The drifting and volume of snow, combined with the lack of available resources to manage it, obliged the community to declare a state of emergency. Projections of increased Arctic precipitation and extreme weather events points to the need for communities to have proper resources and supports, including preparedness and adaptation and mitigation strategies, so they can be better equipped to handle storm and blizzard impacts such as those experienced at Clyde River in the winter of 2021/22. Additional steps that can be implemented to better support and prepare communities include investing in preparedness planning, expanded and enhanced weather information and services, community land-based programming to transfer Inuit knowledge and skills, assessing the usefulness of current forecasts, and new approaches to community planning.

Significance Statement

In this study, we consider the winter of 2021/22, during which the community of Clyde River (Kangiqtugaapik), Nunavut experienced 33 days with blizzard conditions—more than any other year since at least 1978/79. Blizzards are characterized by strong winds and blowing snow. Low visibility impedes travel, and drifting snow blocks roads and can bury equipment and buildings. In this case, broken snow-clearing equipment and other infrastructure challenges also hampered the community’s ability to respond, and residents went days without essential services. Several studies suggest that extreme winds will become more common in the Baffin Bay region in the future. This study demonstrates the need for proper resourcing of communities for preparedness, response, and adaptation strategies, especially with the possibility of extreme winter weather becoming more common.

Open access