Now showing items 30091-30110 of 49060

    • Obduracy and Change in Urban Transport—Understanding Competition Between Sustainable Fuels in Swedish Municipalities

      Amelia Mutter (MDPI AG, 2019-11-01)
      Within the renewable transport transition, a number of alternative technologies have emerged creating competing visions of how to reduce fossil fuel dependence. This paper examines the dynamics of competing fuels in two Swedish municipalities where electric buses have emerged, threatening incumbent biogas-based bus systems. While in Linköping, actors are resistant to the promise of electrification, in Malmö the shift to electrify urban buses has already begun. Here, the theoretical perspectives of obduracy and sociotechnical imaginaries are used to analyze obduracy and change in Linköping and Malmö, showing how the local contexts of these two municipalities influence obduracy or willingness to change. In Linköping, perceived connections between the biogas-based bus system and local infrastructures of renewable waste management and organic food production cause actors to place biogas buses at the center of a sustainable future region, while in Malmö linkages to the gas network (which also distributes natural gas) cause actors to question the sustainability of the fuel in use and opens up the city to welcome new electric vehicle tests. These examples show how fuel alternatives interact with each other in the wider renewable energy transition.
    • Objective and Subjective Determinants of Neighborhood Satisfaction in the Context of Retrofitting Suburbs

      Dorota Mantey (MDPI AG, 2021-10-01)
      A strong preference for suburban living has led to extensively developed suburbs that need retrofitting by improving their compactness. However, an attempt to make suburban areas more sustainable only by shaping their spatial form, without considering individual demands and preferences, is usually ineffective. The aim of this research is to better understand the factors that are important for suburban neighborhood satisfaction and to determine the relationship between neighborhood satisfaction and both the objective spatial attributes reflecting different levels of spatial chaos and satisfaction with particular neighborhood characteristics. The factor analysis and a linear multiple regression model have revealed that there are four significant subjective factors explaining neighborhood satisfaction, namely: assessed suburban assets, assessed accessibility, assessed walkability, and assessed mental and social attitude towards the neighborhood. Among these, the assessed accessibility is the most important predictor of the neighborhood satisfaction and synthetic indicator of spatial chaos the least significant one. Although the research proved that subjective measures are more important determinants of neighborhood satisfaction, fighting urban sprawl should be based on the interference in both subjective evaluations and objective spatial attributes, since two of the four subjective factors are likely to be strongly influenced by improving accessibility in the process of retrofitting suburbs.
    • Objective Building Energy Performance Benchmarking Using Data Envelopment Analysis and Monte Carlo Sampling

      Seong-Hwan Yoon; Cheol-Soo Park (MDPI AG, 2017-05-01)
      An objective measure of building energy performance is crucial for performance assessment and rational decision making on energy retrofits and policies of existing buildings. One of the most popular measures of building energy performance benchmarking is Energy Use Intensity (EUI, kwh/m2). While EUI is simple to understand, it only represents the amount of consumed energy per unit floor area rather than the real performance of a building. In other words, it cannot take into account building services such as operation hours, comfortable environment, etc. EUI is often misinterpreted by assuming that a lower EUI for a building implies better energy performance, which may not actually be the case if many of the building services are not considered. In order to overcome this limitation, this paper presents Data Envelopment Analysis (DEA) coupled with Monte Carlo sampling. DEA is a data-driven and non-parametric performance measurement method. DEA can quantify the performance of a given building given multiple inputs and multiple outputs. In this study, two existing office buildings were selected. For energy performance benchmarking, 1000 virtual peer buildings were generated from a Monte Carlo sampling and then simulated using EnergyPlus. Based on a comparison between DEA-based and EUI-based benchmarking, it is shown that DEA is more performance-oriented, objective, and rational since DEA can take into account input (energy used to provide the services used in a building) and output (level of services provided by a building). It is shown that DEA can be an objective building energy benchmarking method, and can be used to identify low energy performance buildings.
    • Objective Comparison of Achievement Motivation and Competitiveness among Semi-Professional Male and Female Football Players

      Ricardo de la Vega; Jorge Gómez; Raquel Vaquero-Cristobal; Javier Horcajo; Lucía Abenza-Cano (MDPI AG, 2022-04-01)
      The aim of this study was to examine differences in achievement motivation (measured with the Objective Achievement Motivation Test, OLMT, Schuhfried®) and competitiveness between male and female semi-professional football players. The OLMT objectively assessed three constructs regarding achievement motivation: motivation through personal goals, aspiration level, and motivation through competition. In addition, competitiveness was measured with the self-reported Competitiveness-10 Questionnaire. Finally, participants’ performance was assessed by three expert observers in each of ten matches. Thirty-eight football players (men = 27; women = 11) participated in the present study, and no significant differences were found in the Levene test when comparing men and women with respect to the scores obtained in the different measures used in our research. Significant differences were found in the motivation through competition (p = 0.021) as well as in self-reported competitiveness (p = 0.020) as a function of gender, with males showing higher values in both cases. No gender differences were found in aspiration level (p = 0.283) or motivation through personal goals (p = 0.897). Moreover, age and player performance did not modulate gender differences on any measures. No significant correlation was found between motivational measures and performance. In conclusion, it should be noted that the only variable on which gender differences emerged was the level of competitiveness, such that males scored higher than females on both objective and self-reported measures.
    • Objective Environmental Indicators and Subjective Well-Being: Are They Directly Related?

      Gianni Betti; Laura Neri; Marco Lonzi; Achille Lemmi (MDPI AG, 2020-03-01)
      This paper discusses how objective environmental indicators affect the measure of a country’s well-being. The dependent variable in the analysis is subjective well-being (WB), for which the objective environmental variable we use is per capita carbon dioxide (CO<sub>2</sub>) emissions. The paper refers to the relationship between subjective well-being and a set of objective variables representing the four basic types of capital to satisfy human needs and to ensure the well-being of future generations based on the ecological economic systems. Implementing different mediation models, estimated using structural equation modeling, we discover that the objective environmental variable does not directly affects the country’s subjective well-being, while, according to different models, the mediated effects are statistically significant in explaining subjective well-being. The surprising results lead us to think that the environmental risks related to CO<sub>2</sub> emissions might not be correctly perceived by the public.
    • Objective Measurement of the Mode of Commuting to School Using GPS: A Pilot Study

      Emilio Villa-González; Sergio Rosado-López; Yaira Barranco-Ruiz; Manuel Herrador-Colmenero; Cristina Cadenas-Sánchez; Maria Paula Santos; Palma Chillón (MDPI AG, 2019-09-01)
      Background and objectives: Active commuting to school (ACS) is a promising strategy to increase the daily physical activity (PA) in youths. However, more studies are required to objectively quantify the mode of commuting to school, as well as the health impact of this behavior. Thus, the aims of this study were: (1) to objectively determine the mode of commuting to school using GPS; (2) to quantify the sedentary time, PA levels, energy expenditure, and the steps derived from each mode of commuting; and (3) to analyze the associations between ACS trips and sedentary time, PA, energy expenditure, and steps. Participants and Methods: A total of 180 trips to school were detected, which corresponded to 18 adolescents (12 girls, mean age = 15 ± 0.0 years old). Mode of commuting to school was detected using a novel method merging GPS data in the Personal Activity Location Measurement System (PALMS), whereas sedentary time, PA levels, energy expenditure, and steps were objectively evaluated through accelerometry. Logistic regressions were used to analyze the associations of these variables with walking trips. Results: A total of 115 trips were recorded. Most trips were performed by walk (49.5%), followed by vehicle (39.1%) and mixed transport (11.3%). In the active school trips, youths were less likely to spend minutes in sedentary behaviors (OR: 0.481, <i>p</i> = 0.038), a higher increase on Metabolic-Equivalent of Task (METs) (OR: 5.497, <i>p</i> = 0.013), and greater steps (OR: 1.004, <i>p</i> = 0.029) than in the passive school trips (both active and passive modes were objectively measured). Conclusions: ACS (mainly walking) contribute to higher METs and steps in adolescents. GPS could be an appropriate method to objectively evaluate the PA variables related to the ACS trips.
    • Objective Sustainability Assessment in the Digital Economy: An Information Entropy Measure of Transparency in Corporate Sustainability Reporting

      Mohammed Zakaria; Chadi Aoun; Divakaran Liginlal (MDPI AG, 2021-01-01)
      The Internet is now a central enabler for sharing sustainability information. Yet, such enablement is complicated through an exponentially increasing array of information. What is lacking in the digital economy are objective and transparent mechanisms to provide reliable assessments of the published sustainability information in a timely and efficient manner. In addressing such limitation, this research proposes an objective automated mechanism for measuring transparency in sustainability reporting using an information entropy-based approach. Through text-mining methods and expert validation, the study built a sustainability dictionary corpus and then applied the corpus for objectively assessing the relative entropy between the probability distributions of words in the sustainability dictionary and those in corporate reports. To demonstrate its effectiveness, the mechanism was empirically applied to compare sustainability reporting of organizations in the energy sector. Here, the research effectively compared cartels with non-cartels by assessing the sustainability reports of major OPEC (Organization of the Petroleum Exporting Countries) and non-OPEC producers spanning a three-year period and found consistent differences in transparency between the two groups. The findings demonstrate likely normative transparency pressures on disaffiliated producers for which cartels may be immune. The automated mechanism holds important theoretical and practical contributions to the field of sustainability as it provides a rapid and objective means for textual analysis of sustainability information, thus promoting transparency in sustainability reporting in the rapidly evolving digital economy.
    • Objectively-Assessed Physical Activity, Sedentary Behavior, Smartphone Use, and Sleep Patterns Pre- and during-COVID-19 Quarantine in Young Adults from Spain

      Borja Sañudo; Curtis Fennell; Antonio J. Sánchez-Oliver (MDPI AG, 2020-07-01)
      This study assessed the effects of COVID-19 home confinement on physical activity, sedentary behavior, smartphone use, and sleep patterns. Data was collected in a sample of 20 young adults (mean age ± SD: 22.6 ± 3.4 years; 55% males) over seven days pre- and during the COVID-19 lockdown. Objective and subjective physical activity (Accelerometer and the International Physical Activity Questionnaire (IPAQ), respectively), the number of hours sitting (IPAQ), objectively-measured smartphone use (smartphone screen time applications), and objective and subjective sleep (accelerometer and the Pittsburgh Sleep Quality Index, respectively) were assessed. Results revealed significantly greater walking time and mean steps (<i>p</i> < 0.001, d = 1.223 to 1.605), and moderate and vigorous physical activity (<i>p</i> < 0.05, d = 0.568 to 0.616), in the pre- compared with the during-COVID-19 lockdown phase. Additionally, smartphone use (<i>p</i> = 0.009, d = 0.654), sitting time (<i>p</i> = 0.002, d = 1.120), and total sleep (<i>p</i> < 0.004, d = 0.666) were significantly greater in the during- compared with the pre-COVID-19 lockdown phase. Multiple regressions analyses showed associations between physical activity and sedentary behavior and sleep quality. The number of hours sitting per day and moderate-to-vigorous physical activity significantly predicted deep sleep (adj.R<sup>2</sup> = 0.46). In conclusion, this study revealed that during the COVID-19 outbreak, behaviors changed, with participants spending less time engaging in physical activity, sitting more, spending more time using the smartphone, and sleeping more hours. These findings may be of importance to make recommendations, including lifestyle modifications during this time.
    • Objectives for Stakeholder Engagement in Global Environmental Assessments

      Jennifer Garard; Martin Kowarsch (MDPI AG, 2017-09-01)
      Global environmental assessments (GEAs) are among the most large-scale, formalized processes for synthesizing knowledge at the science–policy–society interface. The successful engagement of diverse stakeholders in GEAs is often described as a crucial mechanism for increasing their legitimacy, salience and credibility. However, the diversity of perspectives on the more precise objectives for stakeholder engagement remains largely unclear. The aims of this study are to categorize and characterize the diversity of perspectives on objectives for stakeholder engagement in GEAs; to explore differences in perspectives within and between different stakeholder groups and categories; and to test whether the more practical prioritization and selection of objectives in GEAs can be linked to deliberative policy learning as a higher-level rationale for stakeholder engagement. For these purposes, we conduct a grounded theory analysis and a keyword analysis of interview material and official GEA documents relating to two GEAs: UN Environment’s Fifth Global Environment Outlook and the Working Group III contribution to the Intergovernmental Panel on Climate Change Fifth Assessment Report. Based on the analysis, we identify six categories of objectives and present as hypotheses promising ways forward for prioritizing and characterizing objectives for stakeholder engagement in GEAs, as well as potential reasons for the differences between perspectives on objectives. This study draws attention to the need for future GEA processes to have more explicit discussions on the objectives for stakeholder engagement, as well as the importance of moving towards increasingly deliberative and inclusive assessment processes more broadly.
    • Objectives of Sustainable Development and Youth Employment in Colombia

      Cristian Castillo; Julimar Da Silva; Sandro Monsueto (MDPI AG, 2020-01-01)
      The sustainable development goals (SDGs) aim to raise quality employment, gender equity in access to employment and increase coverage in education. However, in Colombia, high unemployment rates and the informality of young people are risks of achieving these goals. The purpose of this research is to estimate the determinants of youth unemployment and its relationship with SDGs Objective 8, and linking it to the objectives of quality education and gender equity. Using the microdata of the Colombian household survey, DANE, this relationship is estimated with a methodology of age, period, and cohort, through a Probit/Logit Multinomial model. As a novel result for the Colombian case, it is shown that, although new generations of young people are more educated, education per se is not enough to guarantee them a quality insertion into the labor market, penalizing, above all, young women. Lack of work experience and segmentation of the labor market would help explain this outcome. Employment policies, therefore, to achieve the SDGs must not only invest in education, but also expand dual education programs, considering gender.
    • Obligation or Innovation: Can the EU Floods Directive Be Seen as a Tipping Point Towards More Resilient Flood Risk Management? A Case Study from Vorarlberg, Austria

      Magdalena Rauter; Thomas Thaler; Marie-Sophie Attems; Sven Fuchs (MDPI AG, 2019-10-01)
      Environmental change is subject to discussion among scientists, practitioners, and policymakers. As increasing threats to both environment and society are on the agenda, alternative management approaches are gaining importance. This paper focuses on the influence of policy changes on flood risk management. There is evidence that shifts in settlement patterns and population growth might influence the dynamics of flood damage and loss. There is increased pressure to intensify land use, but also to keep free spaces for hazard mitigation and adaptation. In this paper, we focus on new regulative and management approaches associated with the implementation of the European (EU) Floods Directive in Austria. The concept of tipping points, which are defined as turning points for system change, has been applied. Based on semi-structured interviews we evaluate whether or not the implementation of the EU Floods Directive has triggered a system change in flood risk management. Our results show that triggers for change are past flood events and a general need for action rather than the implementation of the directive itself. Changes related to the EU Floods Directive are likely to happen in the long-term; however, these cannot yet be determined. The main challenges are associated with transparency and communication between policymakers and the affected society. So far, the requirements of the first policy cycle of the directive have been fulfilled. The second policy cycle will show further outcomes and potential needs.
    • Observation of the Effect of Gender on Children’s Concept of Motion; Sustainability Issue

      Punsiri Dam-o; Joanna Gondek; Michał Karbowiak; Tadeusz Wibig (MDPI AG, 2018-08-01)
      Determination of the parameters of motion of the surrounding objects, and in particular their speed, is one of the basic skills of a human being. Studies on the development of basic concepts of motion have been carried out for years, exploiting various methods and in different contexts. In our research, we analyzed the effect of school education on the understanding of the phenomenon of motion. We tried to determine its possible short- and long-term cognitive consequences. To achieve this goal, we used the survey method. Our studies show that children differentiate two specific concepts: average speed and instantaneous velocity. In the present work we present how the gender context is superimposed on the general picture. We found that the initial, genuine pre-school concept of speed is different for girls and boys. Our analysis shows also that this gender effect vanishes quickly along with the introduction of physical definitions of kinematical quantities by physics/science curricula. We discuss the methodological aspect of the statistical gender gap measure and we calculate the gender effect chance probability, p-value, to be slightly less than 0.001. The importance of the observed effect for the sustainable science teaching processes is discussed.
    • Observational Analysis of Corner Kicks in High-Level Football: A Mixed Methods Study

      Rubén Maneiro; José Luís Losada; Mariona Portell; Antonio Ardá (MDPI AG, 2021-07-01)
      Corner kicks are one of the most important set pieces in high-level football. The present study aimed to analyze the evolution of the tactical approach to corner kicks in high-performance football. For this, a total of 1704 corner kicks executed in the 192 matches corresponding to the 2010, 2014 and 2018 FIFA World Cups were analyzed. To achieve the proposed objectives, the observational methodology was used. The results show an evolution in the mode of execution of these actions, but instead the success rate remains low. The log-linear test allowed to find significant relationships between some of the most important categorical variables in these actions: match status, number of intervening attackers and time. The decision tree models show that the number of players involved in these actions is the criterion that presents the greatest information gain. These results corroborate previous multivariate studies, although more research is still needed. Finally, the results of the present study can be used by coaches to create different training situations where success in this type of action can be enhanced.
    • Observational Evidence of the Need for Gender-Sensitive Approaches to Wildfires Locally and Globally: Case Study of 2018 Wildfire in Mati, Greece

      Anastasia Zabaniotou; Anastasia Pritsa; E-A Kyriakou (MDPI AG, 2021-02-01)
      The study takes an equality justice perspective to compare resilience against the controlled management of wildfires, for an effective preparedness, which is a prerequisite for equitable mitigation. The objectives were (a) conceptualizing wildfire mitigation by exploring the ties with gender equality to wildfire hazards, (b) taking the case of wildfire 2018 in Mati, Greece, to contribute reducing the country’s gender inequality, and (c) increasing resilience to climate change hazards by considering lessons learnt. The authors underscore the benefits of a workshop-based and instrumental case study methodology for unravelling evidence on the need for gender-sensitive approaches and tools for future planning at local, regional, and global scales. The case study unravels women’s lack of preparedness to wildfires in Greece, their absence in decision-making for fire management, and the need for capacity building to transform communities’ resilience. The literature research and the specific interviews conducted helped bring awareness to the wildfire’s dynamics, in alignment with the fundamental aspect of gender equality, and to ground recommendations for socio-ecological resilience transition and gender-sensitive approaches in fire management, from reactive fire-fighting to proactive integration. Although in the geographical-context, the study can bring widespread geographical awareness, bringing insights for relevance to similar areas worldwide.
    • Observational Scale Matters for Ecosystem Services Interactions and Spatial Distributions: A Case Study of the Ussuri Watershed, China

      Jian Zhang; Hengxing Xiang; Shizuka Hashimoto; Toshiya Okuro (MDPI AG, 2021-09-01)
      Understanding how observational scale affects the interactions and spatial distributions of ecosystem services is important for effective ecosystem assessment and management. We conducted a case study in the Ussuri watershed, Northeast China, to explore how observational scale (1 km to 15 km grid resolution) influences the correlations and spatial distributions of ecosystem services. Four ecosystem services of particular importance for the sustainable development of the study area were examined: carbon sequestration, habitat provision, soil retention, and water retention. Across the observational scales examined, trade-offs and synergies of extensively distributed ecosystem services were more likely to be robust compared with those of sparsely distributed ecosystem services, and hot/cold-spots of ecosystem services were more likely to persist when associated with large rather than small land-cover patches. Our analysis suggests that a dual-purpose strategy is the most appropriate for the management of carbon sequestration and habitat provision, and cross-scale management strategies are the most appropriate for the management of soil retention and water retention in the study area. Further studies to deepen our understanding of local landscape patterns will help determine the most appropriate observational scale for analyzing the spatial distributions of these ecosystem services.
    • Observational Study on the Impact of Large-Scale Photovoltaic Development in Deserts on Local Air Temperature and Humidity

      Wei Wu; Shengjuan Yue; Xiaode Zhou; Mengjing Guo; Jiawei Wang; Lei Ren; Bo Yuan (MDPI AG, 2020-04-01)
      As an important form of clean energy, photovoltaic (PV) power generation is entering a rapid development phase. Qinghai, China is located on the Qinghai-Tibet Plateau. It has sufficient sunlight and rich heat and light resources, includes a large area of the Gobi Desert, and has become China’s largest base for PV power generation. However, large-scale PV development in deserts changes the local surface energy distribution and impacts local microclimates. This study considered the Gonghe PV Power Plant in Qinghai as an example. Three monitoring stations were set up in the PV power plant, transition, and reference areas, and the influence of large-scale PV developments on the local air temperature and humidity was studied based on long-term, multi-point field observation data. The results showed that the overall daytime air temperature in the PV power plant had changed slightly (increased and decreased), while the night-time temperature dropped significantly. Specifically, in spring and summer, the daytime temperature increased slightly, with a maximum increase of 0.34 °C; in autumn and winter, the daytime temperature decreased slightly, with a maximum decrease of 0.26 °C; in all seasons, the night-time temperature decreased, with a maximum decrease of 1.82 °C during the winter night. The relative humidity in the PV power plant generally increased; except for a slight decrease in summer, the daytime and night-time relative humidity in spring, autumn, and winter always increased. The humidification in winter was the most significant, with increases of 5.00% and 4.76% for the transition and reference areas, respectively. The diurnal air temperature and relative humidity ranges in the PV power plant were greater than those outside the PV power plant. The results obtained in this field observation study could serve as a basis for quantitative evaluation of the microclimate effects of large-scale PV development in deserts and provide technical support for guiding the future planning and development of the PV industry.
    • Observations of Strategies Used by Secondary School Teachers in Physical Classrooms to Promote Positive Behaviour

      Mohd Mahzan Awang; Abdul Talib Mohamed Hashim; Tan Kim Hua; Abdul Razaq Ahmad; Nordin Mamat (MDPI AG, 2022-06-01)
      Difficult behaviour in pupils poses a challenge to teachers. Although teachers have been trained to implement various pedagogical strategies, teachers’ spontaneous actions in classrooms may affect pupils’ behaviour. Indeed, teachers may face difficulties in making decisions regarding pupils’ behaviour in the classroom. Therefore, we carried out 12 observations in two schools in Malaysia to analyse a pattern of teachers’ initiatives to promote positive behaviour and discourage negative behaviour in classrooms. The study was carried in two urban national secondary schools located in the capital city of Malaysia, Kuala Lumpur. We observed pupils’ behaviour in response to strategies used by teachers for carrying out teaching and learning in the first ten minutes of the lessons. All 12 lessons were video-recorded, then analysed by three coders by looking at the frequency of the following targeted behaviours (using a checklist): teachers’ action: encouragement, praise, and guidance; pupils’ behaviour: attentive, uninvolved, initiative, and disruptive; teachers’ response: positive and ignore. The data gathered were analysed using an event-based analysis technique. The results indicate that teachers were more likely to guide pupils in lessons. There was less encouragement and praise used in the classroom. A clear pattern from this study is that pupils were more likely to pay attention when a teacher responded to their action positively. The data also show that ignoring pupils’ negative behaviour increases such behaviour (uninvolved and disruptive). The implications of the study suggest that there should be intensive training to increase teachers’ skills in managing pupils’ behaviour in the classroom. A specific module is suggested to be designed and implemented.
    • Observations on Appropriate Technology Application in Indigenous Community Using System Dynamics Modelling

      Paulus Daniel Jokhu; Cat Kutay (MDPI AG, 2020-03-01)
      It is possible to develop a well-sustained society by balancing social, technical, and environmental concerns at the community level. Indigenous governance methods provide enormous prospects for developing well-sustained societies. A limitation is the knowledge gap and lack of interest from dominant cultures. With the application of appropriate technology in development, it is possible for Indigenous communities to adjust technology to their uses and transfer their accumulated knowledge to the development of infrastructure and mechanisms for production incorporating cultural value. Activating such talents within the Indigenous community is important for enabling them to achieve their ideal future. Using participatory design methods, Indigenous people can be brought into the development planning to understand the key variables that limit and influence technology development. System dynamic modelling can be adapted to simulate these new attributes and develop plans and objectives based on outcomes from the model. An example is shown around a case study for community development in Papua, Indonesia. This research is to establish a long-term development plan for all stakeholders, while preserving the value of the Indigenous culture. An analysis of Indigenous social behavioral patterns toward development provides an idea of social-constructive values, which will allow Indigenous community to develop self-sustainable and independent communities.
    • Observed Changes in Meteorological Drought Events during 1981–2020 over Rwanda, East Africa

      Jacqueline Uwimbabazi; Yuanshu Jing; Vedaste Iyakaremye; Irfan Ullah; Brian Ayugi (MDPI AG, 2022-01-01)
      Drought is one of the most complex natural phenomena affecting the life and livelihood of people, especially in the current time of human-induced climate change. This research employs ground-based observations to assess the recent spatiotemporal characteristics of meteorological drought events over Rwanda. The drought is examined based on the Standardized Precipitation Evapotranspiration Index (SPEI) and Standardized Precipitation Index (SPI) at seasonal and annual time scales from 1981 to 2020. The Man–Kendal test was used to evaluate the trends in rainfall, temperature, and SPEI values at the annual scale and during the March to May (MAM) and October to December (OND) seasons. The analysis revealed nonsignificant trends in annual (8.4 mm/decade), MAM (−3.4 mm/decade), and OND (4.5 mm/decade) rainfall, while an apparent significant increasing trend in surface air temperature was obtained during the MAM (0.19 °C/decade), OND (0.2 °C/decade), and annual (0.23 °C/decade) time slices. Overall, the SPEI characteristics indicated that the country is more prone to moderate drought events than severe and extreme drought events during MAM and OND seasons. However, the intensity, duration, and frequency differ spatially among seasons. The findings of this study inform policy and decision-makers on the past experienced drought behavior, which can serve as a baseline for future drought mitigation and adaptation plans.
    • Observed Changes in the Frequency, Intensity, and Spatial Patterns of Nine Natural Hazards in the United States from 2000 to 2019

      J. K. Summers; A. Lamper; C. McMillion; L. C. Harwell (MDPI AG, 2022-03-01)
      There is increasing evidence from across the globe that climate change results in changes in the frequency, location, and impact of natural hazards. Much of this evidence is conceptual, inferential, or simply assumed. To provide objective support to confirm these hypotheses, we constructed county-level time-series datasets (2000–2019) for nine natural hazards for the entire United States. Hazards considered for this study included hurricanes, tropical storms, landslides, wildfires, earthquakes, drought, inland flooding, coastal flooding, and tornadoes. Geospatial analysis techniques were used to calculate the percentage (range: 0–100) of land area in each county exposed to each natural hazard for all the years that hazard data were available. The best available data were acquired from publicly accessible sources. Cumulative distribution functions were calculated for each hazard in five-year intervals to test for statistically significant changes in distribution patterns across the five-year time periods using the Kolmogorov–Smirnov test. There were significant changes in hurricanes, tropical storms, and drought over the two decades; changes in tornadoes, landslides, and wildfires were not significant in terms of frequency, likely due to the site-specific nature of their occurrences. The intensity and spatial distribution and an emerging hot spot and spatial trend analyses and an emerging hot spot and spatial trend analyses were also completed (except for flooding events and earthquakes due to insufficient data). All datasets provide empirical support for earlier inferences concerning the connections between the hazards and climate change. Analyses showed apparent changes in the frequency and intensity of hurricanes, tropical storms, and drought-related to climate change factors. Internal and coastal flooding also demonstrated these connections, although the length of the dataset did not permit significant testing but shows significant hot spots and trending locations. Tornadoes, landslides, and wildfires showed significant hot spots and trending locations, but the specific locational nature of the data did not show significant changes in frequency. Earthquakes showed no significant changes over the time period.