Heejun Chang
Biographic Data
| ID | 3584480 |
|---|---|
| NAME | Heejun Chang |
| GIVEN NAMES | Heejun |
| FAMILY NAME | Chang |
| SIGNATURE | CHANG H |
| AFFILIATIONS | Portland State University |
| ORCID | 0000-0002-5605-6500 |
| VERIFIED | Yes |
| TOTAL WORKS | 32 |
| TOTAL CITATIONS | 39 |
| AUTHOR COUNT | 32 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 2002 |
| LATEST PUBLICATION YEAR | 2025 |
| H-INDEX | 3 |
Who bears the burden? An assessment of vulnerability and resilience to consecutive disasters in the Portland metro region
Climate-related disasters threaten urban areas worldwide, yet gaps remain in understanding how multiple stressors interact to shape resilience. This study examines exposure, vulnerability, and resilience across three consecutive extreme events in the Portland metro area: the September 2020 wildfire-related air pollution, the February 2021 snowstorm, and the June 2021 heatwave. We used geographically weighted regression and Spearman rank correlati…
Scales of Connectivity within Stream Temperature Networks of the Clackamas River Basin, Oregon
Water quality varies along the stream network; thus, considering the directional, dendritic nature of stream networks with surrounding landscape variables is essential in explaining spatial variations of water quality. Using a spatially extensive stream temperature monitoring effort in the Clackamas River Basin in the United States, we first compare spatial scales of analysis of atmospheric, landscape, and in-stream explanatory variables through …
Relating social, ecological, and technological vulnerability to future flood exposure at two spatial scales in four U.S. cities
Stream Distance-Based Geographically Weighted Regression for Exploring Watershed Characteristics and Water Quality Relationships
We developed a novel spatial stream network geographically weighted regression (SSN-GWR) by incorporating stream-distance metrics into GWR. The model was tested for predicting seasonal total nitrogen (TN) and total suspended solids (TSS) concentrations in relation to watershed characteristics for 108 sites in the Han River Basin, South Korea. The SSN-GWR model was run with the average seasonal water quality parameters from 2012 through 2016 and w…
Urban flood risk and green infrastructure: Who is exposed to risk and who benefits from investment? A case study of three U.S. Cities
Pluvial flooding is a serious hazard in inland U.S. cities. City managers and communities are increasingly interested in reducing their pluvial flood risk through the development of green infrastructure (GI) features. This research explores the relationship between pluvial flood exposure and GI placement in three inland cities–Atlanta, Phoenix, and Portland–and analyzes the variation of sociodemographic variables in census block groups (CBG) loca…
The spatial relationship between patterns of disappeared streams and residential development in Portland, Oregon, USA
Disappeared streams are streams that have been buried, removed, or moved as part of the urbanization process. We identified disappeared streams in the Portland, Oregon metropolitan area using historical topographic maps for four time periods, and related them to the history of urban development. The historical maps were used to identify streams visible in older maps but not shown in a more recent version. From 1852 to 1895, 15% of streams disappe…
A social-ecological-technological systems framework for urban ecosystem services
Assessment of urban flood vulnerability using the social-ecological-technological systems framework in six US cities
As urban populations continue to grow through the 21st century, more people are projected to be at risk of exposure to climate change-induced extreme events. To investigate the complexity of urban floods, this study applied an interlinked social-ecological-technological systems (SETS) vulnerability framework by developing an urban flood vulnerability index for six US cities. Indicators were selected to reflect and illustrate exposure, sensitivity…
Using GIS-based spatial analysis to determine urban greenspace accessibility for different racial groups in the backdrop of Covid-19: A case study of four US cities
Understanding Urban Flood Resilience in the Anthropocene: A Social-Ecological-Technological Systems (Sets) Learning Framework
Urban flooding is a major concern in many cities around the world. Together with continuous urbanization, extreme weather events are likely to increase the magnitude and frequency of flood hazards and exposure in populated regions. This article examines the changing pathways of flood risk management (FRM) in Portland, Oregon; Seoul, South Korea; and Tokyo, Japan, which have different histories of land development and flood severity. We used city …
Water Conservation
Water conservation is becoming an important issue across scales as water demand increases, but water supply is likely to diminish owing to population growth and climate change. Water conservation in the urban residential sector is highly related to land use and development density, as well as other socioeconomic and behavioral characteristics of residents. Water conservation in the industrial sector has been the most successful, partially because…
Putting space into modeling landscape and water quality relationships in the Han River basin, South Korea
A community-engaged approach to transdisciplinary doctoral training in urban ecosystem services
Socio-hydrology: An Interplay of Design and Self-Organization in a Multilevel World
Yu, D. J., H. Chang, T. T. Davis, V. Hillis, L. T. Marston, W. S. Oh, M. Sivapalan, and T. M. Waring. 2020. Socio-hydrology: an interplay of design and self-organization in a multilevel world. Ecology and Society 25(4):22. https://doi.org/10.5751/ES-11887-250422
Water and Climate Change
Water plays a central role in sustaining human lives and ecosystems. As climate change is likely to increase both temperature and precipitation variability, the spatial and temporal distribution of freshwater availability will shift on Earth. Additionally, as the intensity of the water cycle increases in a warming world, extreme hydroclimatic events will become more frequent over space and time. Floods and droughts will have huge socioeconomic an…
Developing knowledge systems for urban resilience to cloudburst rain events
Dreams and Migration in South Korea's Border Region: Landscape Change and Environmental Impacts
The border region of South Korea has undergone dramatic social and environmental changes since the late 1990s with shifts in governmental regimes. Under the proliberal government (1997–2007) that enhanced economic ties between North and South Korea, the border region was open for introducing new people and industries. With a new conservative governmental regime in the past decade (2007–2017), social and environmental challenges emerged in the bor…
Interdependent Infrastructure as Linked Social, Ecological, and Technological Systems (Setss) to Address Lock‐in and Enhance Resilience
Traditional infrastructure adaptation to extreme weather events (and now climate change) has typically been techno‐centric and heavily grounded in robustness—the capacity to prevent or minimize disruptions via a risk‐based approach that emphasizes control, armoring, and strengthening (e.g., raising the height of levees). However, climate and nonclimate challenges facing infrastructure are not purely technological. Ecological and social systems al…
Water Conservation
Water conservation is becoming an important global issue as water demand increases but water supply is likely to diminish owing to population growth and climate change. Water conservation in the urban residential sector is highly related to land use and development density, as well as other socioeconomic and behavioral characteristics of residents. Water conservation in the industrial sector has been the most successful partially because of finan…
Water and Climate Change
Water plays a central role in sustaining human lives and ecosystems. As climate change is likely to increase both temperature and precipitation variability, the spatial and temporal distribution of freshwater availability will shift on Earth. Additionally, as the intensity of the water cycle increases in a warming world, extreme hydroclimatic events will become more frequent over space and time. Floods and droughts will have huge socioeconomic an…
An exploratory path analysis of attitudes, behaviors and summer water consumption in the Portland Metropolitan Area
Facilitating collaborative urban water management through university-utility cooperation
Effects of runoff sensitivity and catchment characteristics on regional actual evapotranspiration trends in the conterminous US
An understanding of the role of hydro-climatic and geographic regimes on regional actual evapotranspiration (AET) change is essential to improving our knowledge on predicting water availability in a changing climate. This study investigates the relationship between AET change for a 60 year period (1951–2010) and the runoff sensitivity in 255 undisturbed catchments over the US. The runoff sensitivity to climate change is simply defined as the rela…
Why Land Planners and Water Managers Don't Talk to One Another and Why They Should
Increasing evidence demonstrates that unsustainable land use practices result in human-induced drought conditions, and inadequate water supplies constrain land development in growing cities. Nonetheless, organizational barriers impair coordinated land and water management. Land planning is strongly influenced by political realities and interest groups, while water management is focused on the single-minded goal of providing reliable water for fut…
Tradeoffs Between Water Conservation and Temperature Amelioration In Phoenix and Portland: Implications For Urban Sustainability
This study addresses a classic sustainability challenge—the tradeoff between water conservation and temperature amelioration in rapidly growing cities, using Phoenix, Arizona and Portland, Oregon as case studies. An urban energy balance model— LUMPS (Local-Scale Urban Meteorological Parameterization Scheme)—is used to represent the tradeoff between outdoor water use and nighttime cooling during hot, dry summer months. Tradeoffs were characterized…
Why Land Planners and Water Managers Don't Talk to One Another and Why They Should
Increasing evidence demonstrates that unsustainable land use practices result in human-induced drought conditions, and inadequate water supplies constrain land development in growing cities. Nonetheless, organizational barriers impair coordinated land and water management. Land planning is strongly influenced by political realities and interest groups, while water management is focused on the single-minded goal of providing reliable water for fut…
Climate Change, Land-Use Change, and Floods: Toward an Integrated Assessment
Floods occur from a combination of various hydrological, climatological, and land-use conditions. In this article, we review recent studies to identify primary causes of floods in different regions. These studies suggest that changes in precipitation intensity or amount are responsible for increasing floods in coastal cities, which may also be impacted by sea-level rise and an increase in the incidence of tropical storms due to global warming and…
Spatial Variations of Single-Family Residential Water Consumption in Portland, Oregon
Although water demand theories identify price structures, technology, and individual behavior as determinants of water demand, limited theoretical or empirical evidence suggests a link between urban development patterns and water use. To assess the role of urban development patterns on water demand, we used GIS and statistical models to analyze single-family residential water consumption in the Portland, Oregon, metropolitan area. Our results sho…
Developing knowledge systems for urban resilience to cloudburst rain events
Potential Impacts of Climate Change on Flood-Induced Travel Disruptions: A Case Study of Portland, Oregon, USA
This study investigated potential impacts of climate change on travel disruption resulting from road closures in two urban watersheds in the Portland, Oregon, metropolitan area. We used ensemble climate change scenarios, a hydrologic model, a stream channel survey, a hydraulic model, and a travel forecast model to develop an integrated impact assessment method. High-resolution climate change scenarios are based on the combinations of two emission…
Stream Distance-Based Geographically Weighted Regression for Exploring Watershed Characteristics and Water Quality Relationships
We developed a novel spatial stream network geographically weighted regression (SSN-GWR) by incorporating stream-distance metrics into GWR. The model was tested for predicting seasonal total nitrogen (TN) and total suspended solids (TSS) concentrations in relation to watershed characteristics for 108 sites in the Han River Basin, South Korea. The SSN-GWR model was run with the average seasonal water quality parameters from 2012 through 2016 and w…
Understanding Urban Flood Resilience in the Anthropocene: A Social-Ecological-Technological Systems (Sets) Learning Framework
Urban flooding is a major concern in many cities around the world. Together with continuous urbanization, extreme weather events are likely to increase the magnitude and frequency of flood hazards and exposure in populated regions. This article examines the changing pathways of flood risk management (FRM) in Portland, Oregon; Seoul, South Korea; and Tokyo, Japan, which have different histories of land development and flood severity. We used city …
A community-engaged approach to transdisciplinary doctoral training in urban ecosystem services
Tradeoffs Between Water Conservation and Temperature Amelioration In Phoenix and Portland: Implications For Urban Sustainability
This study addresses a classic sustainability challenge—the tradeoff between water conservation and temperature amelioration in rapidly growing cities, using Phoenix, Arizona and Portland, Oregon as case studies. An urban energy balance model— LUMPS (Local-Scale Urban Meteorological Parameterization Scheme)—is used to represent the tradeoff between outdoor water use and nighttime cooling during hot, dry summer months. Tradeoffs were characterized…
Water resource impacts of climate change in southwestern Bulgaria
Using GIS-based spatial analysis to determine urban greenspace accessibility for different racial groups in the backdrop of Covid-19: A case study of four US cities
Impacts of Climate Change and Urban Development on Water Resources in the Tualatin River Basin, Oregon
We investigated the relative importance of future climate change and land use change in determining the quantity and quality of freshwater resources in northwestern Oregon's Tualatin River Basin using the U.S. Environmental Protection Agency's Better Assessment Science Integrating Point and Nonpoint Sources (BASINS) modeling system. Models were calibrated and validated using historic flow and water quality data between 1990 and 2006. The goodness…
Water resource impacts of climate change in southwestern Bulgaria
Spatial variations of summer precipitation trends in South Korea, 1973–2005
We have investigated the spatial patterns of trends in summer precipitation amount, intensity, and heavy precipitation for South Korea between 1973 and 2005. All stations show increasing trends in precipitation amount during the summer months, with the highest percentage of significant increase in June precipitation for the northern and central western part of South Korea. There is a significant increase in August precipitation for stations in th…
Climate Change, Land-Use Change, and Floods: Toward an Integrated Assessment
Floods occur from a combination of various hydrological, climatological, and land-use conditions. In this article, we review recent studies to identify primary causes of floods in different regions. These studies suggest that changes in precipitation intensity or amount are responsible for increasing floods in coastal cities, which may also be impacted by sea-level rise and an increase in the incidence of tropical storms due to global warming and…
Spatial Variations of Single-Family Residential Water Consumption in Portland, Oregon
Although water demand theories identify price structures, technology, and individual behavior as determinants of water demand, limited theoretical or empirical evidence suggests a link between urban development patterns and water use. To assess the role of urban development patterns on water demand, we used GIS and statistical models to analyze single-family residential water consumption in the Portland, Oregon, metropolitan area. Our results sho…
Potential Impacts of Climate Change on Flood-Induced Travel Disruptions: A Case Study of Portland, Oregon, USA
This study investigated potential impacts of climate change on travel disruption resulting from road closures in two urban watersheds in the Portland, Oregon, metropolitan area. We used ensemble climate change scenarios, a hydrologic model, a stream channel survey, a hydraulic model, and a travel forecast model to develop an integrated impact assessment method. High-resolution climate change scenarios are based on the combinations of two emission…
Geographical analysis of commercial motor vehicle hazardous materials crashes on the Oregon state highway system
Crashes on highways frequently cause hazardous material exposure to the public and the environment. We evaluated differences in hazardous materials-related crashes vs. non-hazardous-material-related commercial motor vehicle crashes occurring from 2000 to 2006 on the Oregon state highway network. The two groups were compared for crash characteristics by χ2 analysis, and spatial clustering was tested using Ripley's K-function and kernel density est…
Impacts of Climate Change and Urban Development on Water Resources in the Tualatin River Basin, Oregon
We investigated the relative importance of future climate change and land use change in determining the quantity and quality of freshwater resources in northwestern Oregon's Tualatin River Basin using the U.S. Environmental Protection Agency's Better Assessment Science Integrating Point and Nonpoint Sources (BASINS) modeling system. Models were calibrated and validated using historic flow and water quality data between 1990 and 2006. The goodness…
Why Land Planners and Water Managers Don't Talk to One Another and Why They Should
Increasing evidence demonstrates that unsustainable land use practices result in human-induced drought conditions, and inadequate water supplies constrain land development in growing cities. Nonetheless, organizational barriers impair coordinated land and water management. Land planning is strongly influenced by political realities and interest groups, while water management is focused on the single-minded goal of providing reliable water for fut…
Tradeoffs Between Water Conservation and Temperature Amelioration In Phoenix and Portland: Implications For Urban Sustainability
This study addresses a classic sustainability challenge—the tradeoff between water conservation and temperature amelioration in rapidly growing cities, using Phoenix, Arizona and Portland, Oregon as case studies. An urban energy balance model— LUMPS (Local-Scale Urban Meteorological Parameterization Scheme)—is used to represent the tradeoff between outdoor water use and nighttime cooling during hot, dry summer months. Tradeoffs were characterized…
Effects of runoff sensitivity and catchment characteristics on regional actual evapotranspiration trends in the conterminous US
An understanding of the role of hydro-climatic and geographic regimes on regional actual evapotranspiration (AET) change is essential to improving our knowledge on predicting water availability in a changing climate. This study investigates the relationship between AET change for a 60 year period (1951–2010) and the runoff sensitivity in 255 undisturbed catchments over the US. The runoff sensitivity to climate change is simply defined as the rela…
An exploratory path analysis of attitudes, behaviors and summer water consumption in the Portland Metropolitan Area
Facilitating collaborative urban water management through university-utility cooperation
Water Conservation
Water conservation is becoming an important global issue as water demand increases but water supply is likely to diminish owing to population growth and climate change. Water conservation in the urban residential sector is highly related to land use and development density, as well as other socioeconomic and behavioral characteristics of residents. Water conservation in the industrial sector has been the most successful partially because of finan…
Water and Climate Change
Water plays a central role in sustaining human lives and ecosystems. As climate change is likely to increase both temperature and precipitation variability, the spatial and temporal distribution of freshwater availability will shift on Earth. Additionally, as the intensity of the water cycle increases in a warming world, extreme hydroclimatic events will become more frequent over space and time. Floods and droughts will have huge socioeconomic an…
Interdependent Infrastructure as Linked Social, Ecological, and Technological Systems (Setss) to Address Lock‐in and Enhance Resilience
Traditional infrastructure adaptation to extreme weather events (and now climate change) has typically been techno‐centric and heavily grounded in robustness—the capacity to prevent or minimize disruptions via a risk‐based approach that emphasizes control, armoring, and strengthening (e.g., raising the height of levees). However, climate and nonclimate challenges facing infrastructure are not purely technological. Ecological and social systems al…
Water and Climate Change
Water plays a central role in sustaining human lives and ecosystems. As climate change is likely to increase both temperature and precipitation variability, the spatial and temporal distribution of freshwater availability will shift on Earth. Additionally, as the intensity of the water cycle increases in a warming world, extreme hydroclimatic events will become more frequent over space and time. Floods and droughts will have huge socioeconomic an…
Developing knowledge systems for urban resilience to cloudburst rain events
Dreams and Migration in South Korea's Border Region: Landscape Change and Environmental Impacts
The border region of South Korea has undergone dramatic social and environmental changes since the late 1990s with shifts in governmental regimes. Under the proliberal government (1997–2007) that enhanced economic ties between North and South Korea, the border region was open for introducing new people and industries. With a new conservative governmental regime in the past decade (2007–2017), social and environmental challenges emerged in the bor…
Water Conservation
Water conservation is becoming an important issue across scales as water demand increases, but water supply is likely to diminish owing to population growth and climate change. Water conservation in the urban residential sector is highly related to land use and development density, as well as other socioeconomic and behavioral characteristics of residents. Water conservation in the industrial sector has been the most successful, partially because…
Putting space into modeling landscape and water quality relationships in the Han River basin, South Korea
A community-engaged approach to transdisciplinary doctoral training in urban ecosystem services
Socio-hydrology: An Interplay of Design and Self-Organization in a Multilevel World
Yu, D. J., H. Chang, T. T. Davis, V. Hillis, L. T. Marston, W. S. Oh, M. Sivapalan, and T. M. Waring. 2020. Socio-hydrology: an interplay of design and self-organization in a multilevel world. Ecology and Society 25(4):22. https://doi.org/10.5751/ES-11887-250422
Assessment of urban flood vulnerability using the social-ecological-technological systems framework in six US cities
As urban populations continue to grow through the 21st century, more people are projected to be at risk of exposure to climate change-induced extreme events. To investigate the complexity of urban floods, this study applied an interlinked social-ecological-technological systems (SETS) vulnerability framework by developing an urban flood vulnerability index for six US cities. Indicators were selected to reflect and illustrate exposure, sensitivity…
Using GIS-based spatial analysis to determine urban greenspace accessibility for different racial groups in the backdrop of Covid-19: A case study of four US cities
Understanding Urban Flood Resilience in the Anthropocene: A Social-Ecological-Technological Systems (Sets) Learning Framework
Urban flooding is a major concern in many cities around the world. Together with continuous urbanization, extreme weather events are likely to increase the magnitude and frequency of flood hazards and exposure in populated regions. This article examines the changing pathways of flood risk management (FRM) in Portland, Oregon; Seoul, South Korea; and Tokyo, Japan, which have different histories of land development and flood severity. We used city …
Geography (28 works) · Environmental Science (27 works) · Ecology (18 works) · Environmental resource management (14 works) · Climate change (12 works) · Flood Risk Assessment and Management (11 works) · Computer Science (10 works) · Geology (10 works) · Environmental planning (9 works) · Business (8 works)