Month: April 2024

Tropical or extratropical cyclones: what drives the compound flood hazard, impact, and risk for the United States Southeast Atlantic coast?

Latest Results

Abstract

Subtropical coastlines are impacted by both tropical and extratropical cyclones. While both may lead to substantial damage to coastal communities, it is difficult to determine the contribution of tropical cyclones to coastal flooding relative to that of extratropical cyclones. We conduct a large-scale flood hazard and impact assessment across the subtropical Southeast Atlantic Coast of the United States, from Virginia to Florida, including different flood hazards. The physics-based hydrodynamic modeling skillfully reproduces coastal water levels based on a comprehensive validation of tides, almost two hundred historical storms, and an in-depth hindcast of Hurricane Florence. We show that yearly flood impacts are two times as likely to be driven by extratropical than tropical cyclones. On the other hand, tropical cyclones are 30 times more likely to affect people during rarer 100-year events than extratropical cyclones and contribute to more than half of the regional flood risk. With increasing sea levels, more areas will be flooded, regardless of whether flooding is driven by tropical or extratropical cyclones. Most of the absolute flood risk is contained in the greater Miami metropolitan area. However, several less populous counties have the highest relative risks. The results of this study provide critical information for understanding the source and frequency of compound flooding across the Southeast Atlantic Coast of the United States.

Causes and dynamic change characteristics of the 2022 devastating floods in Pakistan

Latest Results

Abstract

In 2022, a catastrophic flood triggered by the extreme precipitation in Sind Province, Pakistan. To better understand the comprehensive response of water vapor, rainfall, topography, and flood, the source of water vapor for the flood was calculated by the NCAR Command Language (NCL) application. Simultaneously, the Global Precipitation Measurement (GPM) data was collected from NASA for overlay analysis with water vapor observations. In addition, a digital elevation model (DEM) was also obtained to analyze the impact of topography on flood inundation. Importantly, multi Sentinel-1 data was used to monitor the long-term changes in flood inundation area. The extreme precipitation is dominated by water vapor continue transferred by southwest monsoon, especially impacted by the occurrence of cyclone. Simultaneously, influenced by the steep terrain that located in the north and west of Pakistan, the extreme precipitation first occurred in Islamabad and its adjacent area, subsequently in Punjab Province, and finally concentrated in Sind Province. The surface runoff induced by rainstorm converged in the junction of Sind and Punjab Province with the pattern of fire hose effect. Subsequently, the flood in Indus River in the Sind Province overflow into the low-lying area along the bank of Indus River due to the terrain of Indus River in these regions has the characteristics of over ground river, and the flood flow capacity is lower than that in northern of Pakistan. In addition, the long-term changes in the flood inundation area can be summarized into four stages: increase slowly period (In June), increase slightly period (In July), increase rapidly period (Between August and the beginning of September), rapidly decline period (After September 15, 2022). Importantly, a conceptual model of disaster caused by the fire pipe effect is summarized based on the comprehensive response of water vapor, rainfall, and topography.

Causes and dynamic change characteristics of the 2022 devastating floods in Pakistan

Latest Results

Abstract

In 2022, a catastrophic flood triggered by the extreme precipitation in Sind Province, Pakistan. To better understand the comprehensive response of water vapor, rainfall, topography, and flood, the source of water vapor for the flood was calculated by the NCAR Command Language (NCL) application. Simultaneously, the Global Precipitation Measurement (GPM) data was collected from NASA for overlay analysis with water vapor observations. In addition, a digital elevation model (DEM) was also obtained to analyze the impact of topography on flood inundation. Importantly, multi Sentinel-1 data was used to monitor the long-term changes in flood inundation area. The extreme precipitation is dominated by water vapor continue transferred by southwest monsoon, especially impacted by the occurrence of cyclone. Simultaneously, influenced by the steep terrain that located in the north and west of Pakistan, the extreme precipitation first occurred in Islamabad and its adjacent area, subsequently in Punjab Province, and finally concentrated in Sind Province. The surface runoff induced by rainstorm converged in the junction of Sind and Punjab Province with the pattern of fire hose effect. Subsequently, the flood in Indus River in the Sind Province overflow into the low-lying area along the bank of Indus River due to the terrain of Indus River in these regions has the characteristics of over ground river, and the flood flow capacity is lower than that in northern of Pakistan. In addition, the long-term changes in the flood inundation area can be summarized into four stages: increase slowly period (In June), increase slightly period (In July), increase rapidly period (Between August and the beginning of September), rapidly decline period (After September 15, 2022). Importantly, a conceptual model of disaster caused by the fire pipe effect is summarized based on the comprehensive response of water vapor, rainfall, and topography.

Features of coolant movement at the boundary of jacketless fuel assemblies with fuel rods of various diameters

Latest Results

Abstract

The paper presents the results of experimental studies investigating the peculiarities of coolant movement at the border and in the bordering fuel rods of jacketless fuel assemblies with various fuel rod diameters and type of spacing grids (honeycomb or plate). The study focuses at the effect of the grid type and spacing of fuel rods in neighboring fuel assemblies on the hydrodynamics and mass transfer in the coolant flow. A series of experiments was performed using the created scale model of the boundary area between jacketless fuel assemblies with fuel rods of various diameters. The studies were carried out using the pneumometric method for measuring the static and dynamic flow characteristics, as well as thermocouple measurements.

Features of coolant movement at the boundary of jacketless fuel assemblies with fuel rods of various diameters

Latest Results

Abstract

The paper presents the results of experimental studies investigating the peculiarities of coolant movement at the border and in the bordering fuel rods of jacketless fuel assemblies with various fuel rod diameters and type of spacing grids (honeycomb or plate). The study focuses at the effect of the grid type and spacing of fuel rods in neighboring fuel assemblies on the hydrodynamics and mass transfer in the coolant flow. A series of experiments was performed using the created scale model of the boundary area between jacketless fuel assemblies with fuel rods of various diameters. The studies were carried out using the pneumometric method for measuring the static and dynamic flow characteristics, as well as thermocouple measurements.

Unravelling vulnerabilities: mapping key hazards in the Gori Ganga watershed of Kumaon Himalaya for communication, conservation and management

Latest Results

Abstract

The present study investigates the susceptibility of the Kailash Sacred Landscape in Uttarakhand's Pithoragarh district, focusing on regional-level disaster risk assessment in the Gori Ganga watershed as a case study and aims to prepare foundation maps for recurrent disasters like landslides, floods and forest fires. The techniques of remote sensing & geographic information systems, frequency ratio and correlation analytics were employed to perceive hazard-prone areas in the valley, using a variety of geographical, environmental and anthropogenic predictors. The accuracy of the maps generated by the modelling procedure was assessed using validation data and a receiver operating characteristics curve (ROC) with the area under the curve (AUC). The analysis revealed 83.5 km2 was extremely susceptible to flood incidents, 133.1 km2 was susceptible to landslides and 147 km2 was severely vulnerable to wildfires. The determined area under the curve value for flood susceptibility was 88.6%, followed by landslides at 89.5% and wildfires at 90.9%, showing that the model performed exceptionally well. The findings reveal that precipitation, lithology and elevation were the most significant variables in inducing floods. Precipitation, profile curvature, elevation and distance to thrust are the primary determinants of landslides, while closeness to the road and settlements, as well as vegetation indices, were significant predictors of fire events. The Lower Kumaon Himalayan valley region was recognized as highly vulnerable to all three major catastrophes. This study identifies potentially hazardous regions for adaptive sustainable conservation activities, involving local communities in decision-making to mitigate impacts and aid in preventing and managing impending landscape-level threats.

Unravelling vulnerabilities: mapping key hazards in the Gori Ganga watershed of Kumaon Himalaya for communication, conservation and management

Latest Results

Abstract

The present study investigates the susceptibility of the Kailash Sacred Landscape in Uttarakhand's Pithoragarh district, focusing on regional-level disaster risk assessment in the Gori Ganga watershed as a case study and aims to prepare foundation maps for recurrent disasters like landslides, floods and forest fires. The techniques of remote sensing & geographic information systems, frequency ratio and correlation analytics were employed to perceive hazard-prone areas in the valley, using a variety of geographical, environmental and anthropogenic predictors. The accuracy of the maps generated by the modelling procedure was assessed using validation data and a receiver operating characteristics curve (ROC) with the area under the curve (AUC). The analysis revealed 83.5 km2 was extremely susceptible to flood incidents, 133.1 km2 was susceptible to landslides and 147 km2 was severely vulnerable to wildfires. The determined area under the curve value for flood susceptibility was 88.6%, followed by landslides at 89.5% and wildfires at 90.9%, showing that the model performed exceptionally well. The findings reveal that precipitation, lithology and elevation were the most significant variables in inducing floods. Precipitation, profile curvature, elevation and distance to thrust are the primary determinants of landslides, while closeness to the road and settlements, as well as vegetation indices, were significant predictors of fire events. The Lower Kumaon Himalayan valley region was recognized as highly vulnerable to all three major catastrophes. This study identifies potentially hazardous regions for adaptive sustainable conservation activities, involving local communities in decision-making to mitigate impacts and aid in preventing and managing impending landscape-level threats.

Valuable Beyond Vulnerable: A Scoping Review on the Contributions of Older Forced Migrants in Post-migration Recovery

Latest Results

Abstract

During times of crisis, including pandemics, climate change, and forced migration, much of the discourse in ageing research and intervention centers on the vulnerabilities of older adults. Unfortunately, the valuable contributions of older adults to post-disaster recovery and healing are often overlooked and undervalued. Our aim in this scoping review is to shed light on the critical contributions of older forced migrants to post-migration recovery. We set the scene by introducing the two significant global demographic changes of the twenty-first century: forced migration and ageing. We provide a discourse on older forced migrants, ageing in situations of forced migration, and some of the challenges faced by older forced migrants. We then present some of the substantial roles of older forced migrants in post-migration recovery, including building resilience, contributing to culture and language transfer, providing emotional support, offering mentorship and leadership, participating in community building, and fostering social integration. We close by highlighting some of the lessons that can be drawn from understanding the unique roles played by older adults in post-forced migration recovery and the key actions necessary to promote these roles.

Valuable Beyond Vulnerable: A Scoping Review on the Contributions of Older Forced Migrants in Post-migration Recovery

Latest Results

Abstract

During times of crisis, including pandemics, climate change, and forced migration, much of the discourse in ageing research and intervention centers on the vulnerabilities of older adults. Unfortunately, the valuable contributions of older adults to post-disaster recovery and healing are often overlooked and undervalued. Our aim in this scoping review is to shed light on the critical contributions of older forced migrants to post-migration recovery. We set the scene by introducing the two significant global demographic changes of the twenty-first century: forced migration and ageing. We provide a discourse on older forced migrants, ageing in situations of forced migration, and some of the challenges faced by older forced migrants. We then present some of the substantial roles of older forced migrants in post-migration recovery, including building resilience, contributing to culture and language transfer, providing emotional support, offering mentorship and leadership, participating in community building, and fostering social integration. We close by highlighting some of the lessons that can be drawn from understanding the unique roles played by older adults in post-forced migration recovery and the key actions necessary to promote these roles.