Search Results (100)

Flash floods, exacerbated by climate change and land use alterations, are among the most destructive natural hazards globally, leading to significant damage and loss of life. In this context, the Flash Flood Potential Index (FFPI), which is a terrain and land surface-based model, and Google Earth Engine (GEE) were used to assess flood-prone zones across North Macedonia’s watersheds. The presented GEE-based assessment was accomplished by a custom script that automates the FFPI calculation process by integrating key factors derived from publicly available sources. These factors, which define susceptibility to torrential floods, include slope (Copernicus GLO-30 DEM), land cover (Copernicus GLO-30 DEM), soil type (SoilGrids), vegetation (ESA World Cover), and erodibility (CHIRPS). The spatial distribution of average FFPI values across 1396 small catchments (10–100 km²) revealed that a total of 45.4% of the area exhibited high to very high susceptibility, with notable spatial variability. The CHIRPS rainfall data (2000–2024) that combines satellite imagery and in situ measurements was used to estimate peak 24 h runoff and discharge. To improve the accuracy of CHIRPS, the data were adjusted by 30–50% to align with meteorological station records, along with normalized FFPI values as runoff coefficients. Validation against 328 historical river flood and flash flood records confirmed that 73.2% of events aligned with moderate to very high flash flood susceptibility catchments, underscoring the model’s reliability. Thus, the presented cloud-based scenario highlights the potential of the GEE’s efficacy in scalability and robustness for flash flood modeling and regional risk management at national scale. Full article

Catastrophic floods in monsoon-driven river systems pose significant challenges to flood resilience. In July 2020, China’s Huai River Basin (HRB) encountered an unprecedented basin-wide flood event characterized by anomalous southward displacement of the rain belt. This event established a new historical record with the three typical hydrological stations (Wangjiaba, Runheji, and Lutaizi sections) along the mainstem of the Huai River exceeded their guaranteed water levels within 11 h and synchronously reached peak flood levels within a 9-h window, whereas the inter-station lag times during the 2003 and 2007 floods ranged from 24 to 48 h, causing a critical emergency in the flood defense. By integrating operational hydrological data, meteorological reports, and empirical rainfall-runoff model schemes for the Meiyu periods of 2003, 2007, and 2020, this research systematically dissects the 2020 flood’s spatial composition patterns. Comparative analyses across spatiotemporal rainfall distribution, intensity metrics, and flood peak response dynamics reveal distinct characteristics of southward-shifted torrential rain and flood variability. The findings provide critical technical guidance for defending against extreme weather events and unprecedented hydrological disasters, directly supporting revisions to flood control planning in the Huai River Ecological and Economic Zone. Full article

Assessing flash flood susceptibility is crucial for disaster management, yet Montenegro lacks research using geoinformation technologies. In northeastern Montenegro, the Ibar River Basin, mainly in Rožaje, has a well-developed hydrological network with torrential streams prone to flash flooding. This study compares two multi-criteria GIS decision analysis (GIS–MCDA) methodologies, the Analytic Hierarchy Process (AHP) and the Best-Worst Method (BWM), for assessing flood susceptibility. The analysis uses the Flash Flood Susceptibility Index (FFSI), integrating geoenvironmental and climatic factors. The geoenvironmental criteria considered include terrain slope, distance from the drainage network, geology, land cover, drainage density, bare soil index, and the BIO16 variable, which represents the mean monthly precipitation of the wettest quarter to enhance precipitation pattern assessment. The AHP model classifies 2.78% of the area as high to very high susceptibility, while the BWM model identifies 3.21% in these categories. Both models perform excellently based on AUC values, with minor, non-significant differences. Sensitivity analysis shows AHP provides a more stable weight distribution, whereas BWM is more sensitive to weight changes, emphasizing dominant criteria more strongly. This study introduces BWM for the first time in flash flood modeling, demonstrating its suitability for susceptibility assessment. The key novelty lies in its comparative analysis with AHP, highlighting differences in weight distribution and model stability. Full article

Archival materials are increasingly vulnerable to damage from chemical, physical, biological, and environmental factors, including climate change-related extreme weather events such as torrential rains and flash floods. These conditions pose significant risks to paper-based cultural heritage, leading to degradation from both water and salt exposure. This study investigates the effects of direct immersion in saline solutions on different types of paper, simulating the impact of flooding events. We focused on how varying levels of salinity affect the crystalline structure of paper, which is crucial for understanding its degradation. This study employed non-invasive, portable optical techniques such as luminescence, reflectivity, and Raman spectroscopy to monitor the changes in the paper structure. Our results showed that salt exposure leads to significant alterations in the paper’s crystalline composition. The study concludes that washing treatments are essential for mitigating further degradation, highlighting the importance of timely intervention in preserving cultural heritage. The non-destructive nature of the methods used also demonstrates their potential for in situ applications in cultural heritage conservation. Full article

Mountain areas are prone to the occurrence of extreme events, especially torrential floods, amplified by climatic and environmental changes. In this context, it is mandatory to increase resilience and guide decision-makers toward more effective measures. Life cycle assessment (LCA) is considered as a decision support tool that can provide the qualitative and quantitative criteria required by the Do No Significant Harm, thus contributing to a more accurate assessment of environmental impacts of the torrent control structures. This study aimed to investigate the current state of the LCA applications in the torrent control to provide practitioners perspectives for new research and a pathway for optimized LCA analysis. Our analysis reveals that in the torrent control area, these studies are still limited. Most of the papers considered Ecoinvent as the main database source and cradle to grave as the main system boundary. This study suggests that restoring the functional capacity of dams and other torrent control structures instead of demolition or decommissioning from the end-of-life stage will ensure an orientation towards more sustainable and circular strategies. Although strong partnerships and consistent efforts are needed, general findings reveal that LCA is a useful tool for moving towards more sustainable construction practices. Full article

Flooding is the most pervasive hydrological disaster globally. This study presents a comprehensive analysis of torrential rain and flood characteristics across three major urban agglomerations (CY, MRYR, and YRD) in the Yangtze River Basin from 1991 to 2020. Utilizing satellite-derived microwave SSM/I data and CHIRPS precipitation datasets, this study examines the impacts of urbanization and climate change on flood risk patterns. The results showed: (1) In 1998, the MRYR had the highest flood risk due to heavy rainfall and poor flood control, but by 2020, risk shifted to the CY with rapid urbanization and more rainfall, while the YRD maintained the lowest risk due to advanced flood control. (2) The relationship between impervious surface area and flood risk varied by region. The CY showed a negative correlation (−0.41), suggesting effective flood mitigation through topography and infrastructure; the MRYR had a slight positive correlation (0.12), indicating increased risks from urban expansion; and the YRD’s weak negative correlation (−0.18) reflected strong flood control systems. This research underscores the imperative of strategic urban planning and effective water resource management to mitigate future flood risks and contributes valuable insights to ongoing efforts in flood disaster prevention and control within the Yangtze River Basin. Full article

Due to climate change, the frequency and intensity of torrential rainfall in urban areas are increasing, leading to more frequent flood damage. Consequently, there is a need for a rapid and accurate analysis of urban flood response capabilities. The dual-drainage model has been widely used for accurate flood analysis, with minimum time step synchronization being commonly adopted. However, this method has limitations in terms of speed. This study applied the hyper-connected solution for an urban flood (HC-SURF) model with fixed-time step flow synchronization, validated its accuracy using laboratory observation data, and tested its effectiveness in real urban watersheds with various synchronization times. Excellent performance was achieved in simulating real phenomena. In actual urban watersheds, as the synchronization time increased, the errors in surcharge and discharge also increased due to the inability to accurately reflect water level changes within the synchronization time; however, overall, they remained minimal. Therefore, the HC-SURF model is demonstrated as a useful tool for urban flood management that can be used to advantage in real-time flood forecasting and decision-making. Full article

Extreme rainfall events in Andean basins frequently trigger landslides, obstructing river channels and causing flash flows, loss of lives, and economic damage. This study focused on improving the modeling of these events to enhance risk management, specifically in the La Liboriana basin in Salgar (Colombia). A cascading modeling methodology was developed, integrating the spatially distributed rainfall intensities, hazard zoning with the SLIDE model, propagation modeling with RAMMS using calibrated soil rheological parameters, the distributed hydrological model TETIS, and flood mapping with IBER. Return periods of 2.33, 5, 10, 25, 50, and 100 years were defined and applied throughout the methodology. A specific extreme event (18 May 2015) was modeled for calibration and comparison. The spatial rainfall intensities indicated maximum concentrations in the northwestern upper basin and southeastern lower basin. Six landslide hazard maps were generated, predicting landslide-prone areas with a slightly above random prediction rate for the 2015 event. The RAMMS debris flow modeling involved 30 simulations, indicating significant deposition within the river channel and modifying the terrain. Hydraulic modeling with the IBER model revealed water heights ranging from 0.23 to 7 m and velocities from 0.34 m/s to 6.98 m/s, with urban areas showing higher values, indicating increased erosion and infrastructure damage potential. Full article

This research investigates the effects of land use/land cover (LULC) and demographical changes on runoff and erosion processes in the watersheds of border highlands in Serbia. It provides an interdisciplinary approach, linking demography (human geography) with physical geography (hydrology and geomorphology). (A) A predominant decrease in curve number (CN), a key hydrological indicator, is recorded in more than 20 watersheds in Eastern and Southeastern Serbia, largely due to continuous depopulation and abandonment of arable land over recent decades. In contrast, minor CN changes are dominant in over 10 watersheds in Western and Southwestern Serbia. (B) Through cluster analysis, four regions are spatially delineated by changes in four key indicators: runoff, soil erosion, agricultural land use, and rural population. Soil erosion change is correlated with the deagrarianisation and depopulation processes at a significance of p < 0.0001 with r = 0.580 and r = 0.629, respectively. The border watersheds are being studied for the first time using a complex approach that analyses the relationships between changes in demography, land use, surface runoff, and soil erosion. The study results contribute to a better understanding of sustainable land management and risk management in the hilly and mountainous border regions, which are particularly vulnerable to torrential flooding and soil erosion. Full article

Precipitation data in urban hydrological models are derived from an ideal stormwater model, which has some uncertainties and limited prediction times. Therefore, to reliably forecast urban flooding, prolong prediction time periods, and better support associated research in urban flood forecasting, a combination of weather forecasts and urban hydrology is necessary. By applying comprehensive cloud microphysical schemes in the Weather Research and Forecasting (WRF) model to the predecessor torrential rainfall associated with Typhoon Khanun (2017), this study evaluated different configurations of atmospheric-hydrological simulations based on the WRF model and InfoWorks ICM. Results showed that the microphysics scheme could significantly affect spatial and temporal distributions of the simulated torrential rainfall. Generally, the combination of WRF and NSSL schemes produced better performance. Applying the NSSL scheme to the WRF model and combining it with the InfoWorks ICM system can reproduce torrential rainfall and urban flood formations. Full article

In July 2023, Baoding in Hebei Province experienced unprecedented torrential rainfall, breaking historical records and causing severe flooding. However, our understanding of the multi-scale circulation systems and physical mechanisms driving this extreme precipitation event remains incomplete. This study utilizes multi-source observational data and the Weather Research and Forecasting (WRF) numerical model to conduct a weather diagnosis and numerical simulation of this extreme rainfall event, focusing on the impact of atmospheric rivers (ARS) and urban rooftop roughness on the precipitation process against the background of climate warming. The study found that this extremely heavy rainstorm occurred in the circulation background formed by the factors of subtropical high ectopics, typhoon residual vortex retention, double typhoon water-vapor transmission, and stable high-level divergence. The ARS provided abundant moisture, with its vapor pathway significantly altered following the landfall of Typhoon Doksuri. The interaction between the ARS and the Taihang Mountains was crucial in triggering and intensifying the rainstorm in the foothills. Urbanization significantly affected the distribution of precipitation, with moderate urban roughness enhancing rainfall in and around the city, whereas excessive roughness suppressed it. These results contribute to a deeper understanding of the mechanisms behind extreme precipitation under climate change and provide a scientific basis for improving the forecasting and mitigation of such events. Full article

Soil erosion represents a complex ecological issue that is present on a global level, with negative consequences for environmental quality, the conservation and availability of natural resources, population safety, and material security, both in rural and urban areas. To mitigate the harmful effects of soil erosion, a soil erosion map can be created. Broadly applied in the Balkan Peninsula region (Serbia, Bosnia and Herzegovina, Croatia, Slovenia, Montenegro, North Macedonia, Romania, Bulgaria, and Greece), the Erosion Potential Method (EPM) is an empirical erosion model that is widely applied in the process of creating soil erosion maps. In this study, an innovation in the process of the identification and mapping of erosion processes was made, creating a coefficient of the types and extent of erosion and slumps (φ), representing one of the most sensitive parameters in the EPM. The process of creating the coefficient (φ) consisted of applying remote sensing methods and satellite images from a Landsat mission. The research area for which the satellite images were obtained and thematic maps of erosion processes (coefficient φ) were created is the area of the Federation of Bosnia and Herzegovina and the Brčko District (situated in Bosnia and Herzegovina). The Google Earth Engine (GEE) platform was employed to process and retrieve Landsat 7 Enhanced Thematic Mapper plus (ETM+) and Landsat 8 Operational Land Imager and Thermal Infrared Sensor (OLI/TIRS) satellite imagery over a period of ten years (from 1 January 2010 to 31 December 2020). The mapping and identification of erosion processes were performed based on the Bare Soil Index (BSI) and by applying the equation for fractional bare soil cover. The spatial–temporal distribution of fractional bare soil cover enabled the definition of coefficient (φ) values in the field. An accuracy assessment was conducted based on 190 reference samples from the field using a confusion matrix, overall accuracy (OA), user accuracy (UA), producer accuracy (PA), and the Kappa statistic. Using the confusion matrix, an OA of 85.79% was obtained, while UA ranged from 33% to 100%, and PA ranged from 50% to 100%. Applying the Kappa statistic, an accuracy of 0.82 was obtained, indicating a high level of accuracy. The availability of a time series of multispectral satellite images for each month is a crucial element in monitoring the occurrence of erosion processes of various types (surface, mixed, and deep) in the field. Additionally, it contributes significantly to decision-making, strategies, and plans in the domain of erosion control work, the development of plans for identifying erosion-prone areas, plans for defense against torrential floods, and the creation of soil erosion maps at local, regional, and national levels. Full article

Rehabilitating water-damaged structures in buildings results in increased material extraction and energy use, and, consequently, a higher carbon footprint of the housing industry. Despite its prevalence, quantifying the carbon footprint caused by water damage or flooding has not gained much attention. Thus, this study investigated the quantitative carbon footprint associated with rehabilitating flooding in a detached house caused by torrential rain. Three different construction methods of the house were looked at; a timber frame construction, a masonry variant made by concrete blocks of Lightweight Expanded Clay Aggregate (LECA), and an alternative with exterior walls composed of concrete-moulded Expanded Polystyrene (EPS) foam boards. A life-cycle assessment according to NS 3720 was used to investigate the carbon footprint (CO_2eq.) of typical flooding in a detached building. Rehabilitating the flooding in a house with concrete-moulded boards resulted in a lower carbon footprint (2.45 × 10³ CO_2eq.) than rehabilitating the same flooding in a house with LECA masonry (7.56 × 10³ CO_2eq.) and timber frames (2.49 × 10³ CO_2eq.). However, the timber-frame house had the lowest total carbon footprint (2.95 × 10⁴ CO_2eq.) owing to their original low footprint. This study found that flooding significantly contributed to the carbon footprint of buildings and, therefore, the topic should be given attention when choosing a construction method and moisture safety strategy. Full article

Japan’s susceptibility to and severity of floods have necessitated flood control policies by the government. “Overflowing flood control”, in which the floods due to torrential rains are systematically diverted to agricultural lands in the upper to middle reaches, is one of them. More information is needed on the public assessment of the overflowing flood control policy, and this research seeks to bridge this gap. Data evaluating rice affected by the policy were collected from a random nth-price auction using a developed online system. The sample consisted of 47 consumers living in the downstream areas of the Edogawa River, one of Japan’s first-class, or prime, rivers. Data on their attitudes toward the policy were collected with a questionnaire. Multiple ordered probit models are used for regression analysis. The results show that the sample respondents were willing to pay an average of JPY 1578 for 5 kg of rice, slightly higher than the national average rice production cost, and that 36% of the sample agreed with the flood control policy, which is positively associated with large families or owning many assets. Full article

Road structures undergo a series of chemical and physical processes once they are put into service. This phenomenon results from the action of the load and the influence of the environment, which causes their progressive deterioration. In order to mitigate the risk of progressive deterioration and guarantee their stability and durability, various maintenance tasks are required, including visual inspections. The Intelligent Bridge Management System of Colombia (SIGP) includes visual inspection as one of its modules. The system has been designed based on state-of-the-art criteria and national experience with relevant damages and bridge collapses. This paper presents the visual inspection methodology, which includes several stages such as a classification scale, condition index, evaluation areas, damage catalog, and evaluation criteria. In addition, a digital application has been developed to facilitate real-time data collection during field inspections using mobile devices, which can be uploaded directly to the system database hosted in the cloud. The results from the inspection of bridges of different typologies and years of construction are presented, as well as general inspection results from 150 bridges in Colombia. The relevance, comprehensiveness, and accuracy of the inspection are supported by a damage catalog, which allows the identification of intervention needs and reduces the bias of the collected data. Full article