24 research outputs found
Assessing the role of human behaviors in the management of extreme hydrological events: an agent-based modeling approach
This thesis aims to assess the role of human behaviors in the management of extreme hydrological events. Using an agent-based modeling (ABM) approach, three specific issues associated with modeling human behaviors are addressed: (1) behavioral heterogeneity, (2) social interaction, and (3) the interplay of multiple behaviors. The modeling approach is applied to two types of extreme hydrological events: floods and droughts.
In the case of flood events, an ABM is developed to simulate heterogeneous responses to flood warnings and evacuation decisions. The ABM is coupled with a traffic model to simulate evacuation processes on a transportation network in an impending flood event. Based on this coupled framework, the model further takes account of social interactions, in the form of communication through social media, and evaluates how social interactions affect flood risk awareness and evacuation processes.
The case of drought events considers a hypothetical agricultural water market based on double auction. Farmersâ multiple behaviors (irrigation and bidding behaviors) are modeled in an ABM framework. The impacts of the interplay of these behaviors on water market performance are evaluated under various hydrological conditions.
The results from the ABMs show that the three aforementioned aspects of human behaviors can significantly affect the effectiveness of the management policies in extreme hydrological events. The thesis highlights the importance of including human behaviors for policy design in flood and drought management. Further, the thesis emphasizes the efforts in collecting empirical data to better represent and simulate human behaviors in coupled human and hydrological systems
Evaluating the impacts of farmersâ behaviors on a hypothetical agricultural water market based on double auction
Agricultural water markets are considered effective instruments to mitigate the impacts of water scarcity and to increase crop production. However, previous studies have limited understanding of how farmersâ behaviors affect the performance of water markets. This study develops an agent-based model to explicitly incorporate farmersâ behaviors, namely irrigation behavior (represented by farmersâ sensitivity to soil water deficit k) and bidding behavior (represented by farmersâ rent seeking l and learning rate b), in a hypothetical water market based on a double auction. The model is applied to the Guadalupe River Basin in Texas to simulate a hypothetical agricultural water market under various hydrological conditions. It is found that the joint impacts of the behavioral parameters on the water market are strong and complex. In particular, among the three behavioral parameters, k affects the water market potential and its impacts on the performance of the water market are significant under most scenarios. The impacts of l or b on the performance of the water market depend on the other two parameters. The water market could significantly increase crop production only when the following conditions are satisfied: (1) k is small and (2) l is small and/or b is large. The first condition requires efficient irrigation scheduling, and the second requires well-developed water market institutions that provide incentives to bid true valuation of water permits
Exploring the Role of Social Media and Individual Behaviors in Flood Evacuation Processes: An Agent-Based Modeling Approach
Flood warnings from various information sources are important for individuals to make evacuation decisions during a flood event. In this study, we develop a general opinion dynamics model to simulate how individuals update their flood hazard awareness when exposed to multiple information sources, including global broadcast, social media, and observations of neighbors' actions. The opinion dynamics model is coupled with a traffic model to simulate the evacuation processes of a residential community with a given transportation network. Through various scenarios, we investigate how social media affect the opinion dynamics and evacuation processes. We find that stronger social media can make evacuation processes more sensitive to the change of global broadcast and neighbor observations, and thus, impose larger uncertainty on evacuation rates (i.e., a large range of evacuation rates corresponding to sources of information). For instance, evacuation rates are lower when social media become more influential and individuals have less trust in global broadcast. Stubborn individuals can significantly affect the opinion dynamics and reduce evacuation rates. In addition, evacuation rates respond to the percentage of stubborn agents in a nonlinear manner, i.e., above a threshold, the impact of stubborn agents will be intensified by stronger social media. These results highlight the role of social media in flood evacuation processes and the need to monitor social media so that misinformation can be corrected in a timely manner. The joint impacts of social media, quality of flood warnings, and transportation capacity on evacuation rates are also discussed.Additional
support was provided by Shenzhen
Municipal Science and Technology
Innovation Committee
(#ZDSY20150831141712549)
Assessing the role of human behaviors in the management of extreme hydrological events: an agent-based modeling approach
This thesis aims to assess the role of human behaviors in the management of extreme hydrological events. Using an agent-based modeling (ABM) approach, three specific issues associated with modeling human behaviors are addressed: (1) behavioral heterogeneity, (2) social interaction, and (3) the interplay of multiple behaviors. The modeling approach is applied to two types of extreme hydrological events: floods and droughts.
In the case of flood events, an ABM is developed to simulate heterogeneous responses to flood warnings and evacuation decisions. The ABM is coupled with a traffic model to simulate evacuation processes on a transportation network in an impending flood event. Based on this coupled framework, the model further takes account of social interactions, in the form of communication through social media, and evaluates how social interactions affect flood risk awareness and evacuation processes.
The case of drought events considers a hypothetical agricultural water market based on double auction. Farmersâ multiple behaviors (irrigation and bidding behaviors) are modeled in an ABM framework. The impacts of the interplay of these behaviors on water market performance are evaluated under various hydrological conditions.
The results from the ABMs show that the three aforementioned aspects of human behaviors can significantly affect the effectiveness of the management policies in extreme hydrological events. The thesis highlights the importance of including human behaviors for policy design in flood and drought management. Further, the thesis emphasizes the efforts in collecting empirical data to better represent and simulate human behaviors in coupled human and hydrological systems
Evaluating the impacts of farmersâ behaviors on a hypothetical agricultural water market based on double auction
Agricultural water markets are considered effective instruments to mitigate the impacts of water scarcity and to increase crop production. However, previous studies have limited understanding of how farmersâ behaviors affect the performance of water markets. This study develops an agent-based model to explicitly incorporate farmersâ behaviors, namely irrigation behavior (represented by farmersâ sensitivity to soil water deficit k) and bidding behavior (represented by farmersâ rent seeking l and learning rate b), in a hypothetical water market based on a double auction. The model is applied to the Guadalupe River Basin in Texas to simulate a hypothetical agricultural water market under various hydrological conditions. It is found that the joint impacts of the behavioral parameters on the water market are strong and complex. In particular, among the three behavioral parameters, k affects the water market potential and its impacts on the performance of the water market are significant under most scenarios. The impacts of l or b on the performance of the water market depend on the other two parameters. The water market could significantly increase crop production only when the following conditions are satisfied: (1) k is small and (2) l is small and/or b is large. The first condition requires efficient irrigation scheduling, and the second requires well-developed water market institutions that provide incentives to bid true valuation of water permits
Initiatives on exploring the mechanism of ecoâhydrological response to land surface change and adaptive regulation in the Yellow River Basin
Abstract The Yellow River Basin faces water scarcity and ecological fragility. Changes on the land surface, characterized by largeâscale soil and water conservation measures, have a significant impact on river runoff and ecological environment. However, there are still great uncertainties in the scientific understanding of the mechanisms by which multiple driver impact ecoâhydrological processes due to the diversity of land surfaces and the complexity of the coupling processes. As an international scientific frontier on interdisciplinary studies in climatology, hydrology, ecology, and other related fields, it is significant to study the mechanisms and assess the impacts of land surface change on ecoâhydrological risk to support ecological restoration plan and sustainable water resources utilization in the Yellow River Basin. Taking the Yellow River Basin as the study area, this study proposes several important research initiatives, focusing on addressing the ecological and water resources problems in the Loess Plateau. These initiatives include (1) to quantify the individual effect of land surface elements (e.g., vegetation, terraces, and check dam) and reveal the nonlinear driving mechanisms of multiple drivers on ecoâhydrological processes; (2) to construct a distributed ecoâhydrological model that couples dynamic land surface features, and simulate ecoâhydrological processes in a changing environment; (3) to improve the ecological risk assessment indicator system and methods for assessing the impacts of land surface changes on ecoâhydrological synergistic functions and ecological risk; (4) to establish an ecological regulation model based on multiobjective game theory and adopt an adaptive regulation mode for ecological risk management. The research could enrich the scientific understanding and theory of ecoâhydrology, and prompt disciplinary studies of ecology, hydrology, climatology, and other fields. The expected academic achievements will innovate ecoâhydrological simulation and assessment techniques in a changing environment, and strongly support the implementation of the national strategy for ecological protection and highâquality development in the Yellow River Basin