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A modeling system for the estimation of flash flood flow velocity and
sediment transport is developed in this study. The system comprises three
components: (a) a modeling framework based on the hydrological model HSPF,
(b) the hydrodynamic module of the hydraulic model MIKE 11 (quasi-2-D), and
(c) the
advection–dispersion module of MIKE 11 as a sed...
Context in source publication
Context 1
... maps were generated for each of the three weed-cutting sce- narios and were combined according to Eq. (5) in order to de- rive the hazard rating map for each case. Figures 4-6 present the water depth, flow velocity, and the hazard rating map for scenarios A, B and C, respectively. As can be seen in the haz- ard rating maps, the flood hazard ratings were divided into four classes of different degree (low, moderate, significant and extreme) (Defra/Environment Agency, 2006). ...
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![Fig. 1-Schematic representation of the MIKE SHE model, source: [13]](publication/313371473/figure/fig5/AS:668793076473862@1536464103590/Schematic-representation-of-the-MIKE-SHE-model-source-13_Q320.jpg)
Flash floods are highly variable phenomena in both time and space. Therefore, tools with the potential to provide early warning are needed to analyse them. In Europe, flash floods often occur on small catchments; it has already been shown that the spatial variability of rainfall has a great impact on the catchment response. The aim of this paper is...
Citations
... The optimal plan is for the traps in the T2 treatments to collect lower amounts of water compared to the T1 treatments and this was verified by the results. This is also very important if we think of the case of flash flood events, commonly occurring in semiarid Mediterranean environments [46]. The results of the present study concerning water retention could verify the hypothesis of large-scale studies [47], that if natural barriers are established at sloping farms of semi-mountainous areas (river basin scale) the amounts of runoff water that will reach downstream areas could be lower, mitigating the effects of floods in these areas. ...
Despite the fact that the olive tree is one of the best-adapted species in Mediterranean hydroclimate conditions, climate extremes impose negative effects on olive fruit set and development and subsequently on crop yield. Considering that the frequency of climate extremes is increasing in the last years due to climate change, Good Agricultural Practices (GAPs) have to be applied in order to mitigate their impact on olive trees. In this context, 18 experimental olive groves (irrigated and rainfed) were established, located on the island of Crete (south Greece). A set of 13 GAPs were applied in different combinations, mainly targeting to reduce water losses and erosion, alleviate heat stress and increase water use efficiency. Each experimental orchard was divided into two parts, the control (business-as-usual) and experimental (GAPs implementation). Four indicators were used for the assessment of GAPs performance, namely, Water Productivity (WP), Economic Water Productivity (EWP), Runoff (RF), and Yield (Y). WP and EWP were found to be up to 2.02 and 2.20 times higher, respectively, in the demonstration part of the orchards compared to the control, while Y was found to be up to 119% higher. RF was higher up to 190% in the control compared to the demonstration part of the experimental orchards. The above results clearly demonstrate that the implementation of the proposed GAPs can significantly support the adaptation of olive crops to extreme conditions.
... These models allow to simulate superficial and groundwater dynamics accounting for different hydrological processes (including WD) and can be summarized as it follows: one-dimensional 1D models as ESTRY, HEC-RAS, ISIS, MIKE 11, RUBICON, SOBEK, SWMM (Knebl et al., 2005;Kourgialas and Karatzas, 2014;Stoleriu et al., 2020;Vozinaki et al., 2012) or 2D models for flood mapping, as TUFLOW, MIKE 21, DELFT-FLS, RMA, FESWMS, TELEMAC (Banks et al., 2014;Ghimire, 2013;Ligier, 2016;Robins and Davies, 2011;Syme, 2001). ...
After an extreme rainy event agricultural fields can be submerged by water. Stagnant water can be generated by river’ flooding or by soil saturation causing different damage level to crops. In this work, the flood event occurred on 3rd October 2020 in NW Italy along the Sesia river was assessed with special concern about damages affecting rice crop fields. A method was proposed aimed at detecting flooded areas and giving an estimate of water depth (WD) based on free available Copernicus data (Sentinel-1 and Sentinel-2) and digital terrain model (DTM). In particular, Sentinel-1 pre- and post-event images were compared by differencing (ΔVV). ΔVV was processed at pixel level to detect submerged areas through the thresholding Otsu’s method. A simplified morphological analysis was then performed by DTM tessellation to map WD. A further step aimed at classifying submerged areas was achieved based on DTM and a proximity analysis, making possible to separate areas where water was related to soil saturation from areas where water was coming from the river. Corine Land Cover 2018 level-3 and NDVI from a Sentinel-2 pre-event image were used to map crops that were still to be harvested at the time of flood. These were the ones that were considered while estimating the potential economic loss. A total of 255 ha of rice that still to be harvested were submerged but only 211 ha were affected by river overflow. Using local rice yield and price the resulting economic loss was about 2,200,000 €.
... In contrast, the particles that comport themselves as individual particles are termed non-cohesive gravel and could either be bedload or suspended (Kourgialas and Karatzas 2014). ...
Under climate change and pressure from human activities, extreme flood events are becoming a significant concern. The study involves setting up a coupled hydroclimate-hydrodynamic models over the Ganga River Basin by coupling the CORDEX regional climate models to the physically based Soil Water Assessment Tool-based hydrological model and MIKE 21C-based hydrodynamic model. The coupled model was employed to explore the flood inundation and dynamics of sediment mobilization amid various extreme events under future conditions. The water level, particularly for the 40-year return period for the late century (2061–2100), is estimated to rise in the future (0.9–1.2m). Since extreme streamflow has increased in the future, morphological transformations will also aggravate. Moreover, during the extreme events, the peaks in shear stress and velocity profile distribution have a propensity to coincide with the areas of the meander bend, implying that the river meander processes govern the shifts in the dynamics of the sediment transport. Additionally, the developed model framework has been employed to determine the areas affected and inundation pattern due to the 18 August 2008 flood in the Kosi River due to the embankment breach. Simulation exhibited that there is a good agreement between the simulated and observed inundation areas. Together with the evaluation of the susceptibility corresponding to lives and livelihoods, this information may facilitate decision-makers to develop ameliorative policies and adopt meaningful measures to alleviate the impacts.
... Depending on the respective topography urban floods can develop high flow rates and thereby transport large amounts of sediment and flotsam as well as contamination by chemicals and sewage [65]. Thus, apart from water depth and flow velocity also the parameter of sediment transport is of crucial importance for assessing the hazard potential of pluvial flood events [66]. In the current model, the sediment transport is not considered such that cascading damage effects are not represented. ...
The effective forecast and warning of pluvial flooding in real time is one of the key elements and remaining challenges of an integrated urban flood risk management. This paper presents a new methodology for integrating risk-based solutions and 2D hydrodynamic models into the early warning process. Whereas existing hydrodynamic forecasting methods are based on rigid systems with extremely high computational demands, the proposed framework builds on a multi-model concept allowing the use of standard computer systems. As a key component, a pluvial flood alarm operator (PFA-Operator) is developed for selecting and controlling affected urban subcatchment models. By distributed computing of hydrologic independent models, the framework overcomes the issue of high computational times of hydrodynamic simulations. The PFA-Operator issues warnings and flood forecasts based on a two-step process: (1) impact-based rainfall thresholds for flood hotspots and (2) hydrodynamic real-time simulations of affected urban subcatchments models. Based on the open-source development software Qt, the system can be equipped with interchangeable modules and hydrodynamic software while building on the preliminary results of flood risk analysis. The framework was tested using a historic pluvial flood event in the city of Aachen, Germany. Results indicate the high efficiency and adaptability of the proposed system for operational warning systems in terms of both accuracy and computation time.
... The impacts of climate change are more dramatic in regions with intense competition for natural resources between agriculture and other economic sectors or in ecosystems that are prone to environmental degradation [7]. Today, there are still many farmers who do not use environmentally friendly cultivation methods with effect on climate change [8][9][10]. In addition, intensification of olive cultivation across the Mediterranean has been encouraged by subsidies from the European Union leading to rapid landscape change [11]. ...
Olive cultivation is considered as one of the most significant agricultural activities in Greece, from a financial, social, and ecological point of view. Intensive cultivation practices in combination with the Mediterranean climate, lead to depletion of soil organic matter, erosion, desertification, and degradation of water resources. This paper describes sustainable olive crop management practices that were comparatively applied in 120 olive groves in Greece for 5 years with the participation of three farmers groups. Organic materials recycled in the olive groves during the present study were valuable sources of carbon, nitrogen, phosphorus, and potassium. Carbon content was highest in pruning residue (53.8-54.2%) while all materials studied were considered rich in C ranging between 41.9-46.2% (compost) and 34.9-42.5% (three-phase olive mill waste-OMW). The highest content in nitrogen was detected in compost (2-2.45%) followed by pruning residue (0.93-0.99%) and OMW (0.03-0.1%). Compost was considered a good source of phosphorus (0.3-0.6%) followed by pruning residue (0.08-0.13%) and OMW (0.01-0.3%). Potassium was also considerable in the organic materials recycled ranging 0.5-1.5% in compost followed by pruning residue (0.5-0.7%) and OMW (0.3-1.1%). Adoption of modified pruning also had important contribution toward sustainable management of olive trees. Sustainable pruning resulted in a well-balanced ratio between vegetative growth and fruiting (balanced, every year, in order to eradicate biennial bearing). Significant fluctuation in olive yields was observed in the first years of the project while yields were gradually stabilised by applying sustainable crop management. In parallel, yield increase without additional inputs, lowers the carbon-environmental footprint of the product regarding several environmental impact categories. Results can be integrated in the national agricultural and environmental policy in Mediterranean countries toward the achievement of a circular economy. Climate 2020, 8, x FOR PEER REVIEW 2 of 11
... The impacts of climate change are more dramatic in regions with intense competition for natural resources between agriculture and other economic sectors or in ecosystems that are prone to environmental degradation [7]. Today, there are still many farmers who do not use environmentally friendly cultivation methods with effect on climate change [8][9][10]. In addition, intensification of olive cultivation across the Mediterranean has been encouraged by subsidies from the European Union leading to rapid landscape change [11]. ...
Olive cultivation is considered as one of the most significant agricultural activities in Greece, from a financial, social, and ecological point of view. Intensive cultivation practices in combination with the Mediterranean climate, lead to depletion of soil organic matter, erosion, desertification, and degradation of water resources. This paper describes sustainable olive crop management practices that were comparatively applied in 120 olive groves in Greece for 5 years with the participation of three farmers groups. Organic materials recycled in the olive groves during the present study were valuable sources of carbon, nitrogen, phosphorus, and potassium. Carbon content was highest in pruning residue (53.8–54.2%) while all materials studied were considered rich in C ranging between 41.9–46.2% (compost) and 34.9–42.5% (three-phase olive mill waste-OMW). The highest content in nitrogen was detected in compost (2–2.45%) followed by pruning residue (0.93–0.99%) and OMW (0.03–0.1%). Compost was considered a good source of phosphorus (0.3–0.6%) followed by pruning residue (0.08–0.13%) and OMW (0.01–0.3%). Potassium was also considerable in the organic materials recycled ranging 0.5–1.5% in compost followed by pruning residue (0.5–0.7%) and OMW (0.3–1.1%). Adoption of modified pruning also had important contribution toward sustainable management of olive trees. Sustainable pruning resulted in a well-balanced ratio between vegetative growth and fruiting (balanced, every year, in order to eradicate biennial bearing). Significant fluctuation in olive yields was observed in the first years of the project while yields were gradually stabilised by applying sustainable crop management. In parallel, yield increase without additional inputs, lowers the carbon—environmental footprint of the product regarding several environmental impact categories. Results can be integrated in the national agricultural and environmental policy in Mediterranean countries toward the achievement of a circular economy.
... Furthermore, soil moisture provides information, prediction and forecasting on flood before rainstorms. At the saturation level of soil, floods will likely to occur during the event of rain as its capacity to hold water has reached a limit and thus is unable to absorb an adequate amount of water [10][11][12]. Among others, Reference [13] stressed the importance of soil moisture information for meteorologists, since this parameter is related to weather changes, thereby providing a more accurate weather forecast. ...
Soil moisture represents a vital component of the ecosystem, sustaining life-supporting activities at micro and mega scales. It is a highly required parameter that may vary significantly both spatially and temporally. Due to this fact, its estimation is challenging and often hard to obtain especially over large, heterogeneous surfaces. This study aimed at comparing the performance of four widely used interpolation methods in estimating soil moisture using GPS-aided information and remote sensing. The Distance Weighting (IDW), Spline, Ordinary Kriging models and Kriging with External Drift (KED) interpolation techniques were employed to estimate soil moisture using 82 soil moisture field-measured values. Of those measurements, data from 54 soil moisture locations were used for calibration and the remaining data for validation purposes. The study area selected was Varanasi City, India covering an area of 1535 km2. The soil moisture distribution results demonstrate the lowest RMSE (root mean square error, 8.69%) for KED, in comparison to the other approaches. For KED, the soil organic carbon information was incorporated as a secondary variable. The study results contribute towards efforts to overcome the issue of scarcity of soil moisture information at local and regional scales. It also provides an understandable method to generate and produce reliable spatial continuous datasets of this parameter, demonstrating the added value of geospatial analysis techniques for this purpose.
... Furthermore, soil moisture provides information, prediction and forecasting on flood before rainstorms. At the saturation level of soil, floods will likely to occur during the event of rain as its capacity to hold water has reached a limit and thus is unable to absorb an adequate amount of water [10][11][12]. Among others, Reference [13] stressed the importance of soil moisture information for meteorologists, since this parameter is related to weather changes, thereby providing a more accurate weather forecast. ...
Soil moisture represents a vital component of the ecosystem, sustaining life-supporting activities at micro and mega scales. It is a highly required parameter that may vary significantly both spatially and temporally. Due to this fact, its estimation is challenging and often hard to obtain especially over large, heterogeneous surfaces. This study aimed at comparing the performance of four widely used interpolation methods in estimating soil moisture using GPS-aided information and remote sensing. The Distance Weighting (IDW), Spline, Ordinary Kriging models and Kriging with External Drift (KED) interpolation techniques were employed to estimate soil moisture using 82 soil moisture field-measured values. Of those measurements, data from 54 soil moisture locations were used for calibration and the remaining data for validation purposes. The study area selected was Varanasi City, India covering an area of 1535 km 2. The soil moisture distribution results demonstrate the lowest RMSE (root mean square error, 8.69%) for KED, in comparison to the other approaches. For KED, the soil organic carbon information was incorporated as a secondary variable. The study results contribute towards efforts to overcome the issue of scarcity of soil moisture information at local and regional scales. It also provides an understandable method to generate and produce reliable spatial continuous datasets of this parameter, demonstrating the added value of geospatial analysis techniques for this purpose.
... Rainfall-runoff and hydraulic models have commonly been used to characterize the probability of occurrence and the impacts of floods (e.g., [40]). This involves simulating riverine floods associated with precipitation events of different return periods (T), and route them in a hydraulic model. ...
Multi-hazard evaluations are fundamental inputs for disaster risk management plans and the implementation of resilient urban environments, adapted to extreme natural events. Risk assessments from natural hazards have been typically restricted to the analysis of single hazards or focused on the vulnerability of specific targets, which might result in an underestimation of the risk level. This study presents a practical and effective methodology applied to two Chilean coastal cities to characterize risk in data-poor regions, which integrates multi-hazard and multi-vulnerability analyses through physically-based models and easily accessible data. A matrix approach was used to cross the degree of exposure to floods, landslides, tsunamis, and earthquakes hazards, and two dimensions of vulnerability (physical, socio-economical). This information is used to provide the guidelines to lead the development of resilience thinking and disaster risk management in Chile years after the major and destructive 2010 Mw8.8 earthquake.
... Such long-lasting groundwater flood can cause not only significant damage to infrastructure (Abboud et al., 2017) flooding (Huntingford et al., 2014). Mapping groundwater flood prone area is more challenging compared to river flooding, due to many controlling factors and spatial uncertainties throughout the whole watershed, including topography, land use, geology, etc. Kourgialas and Karatzas (2014) integrated 6 factors: flow accumulation, slope, land use, rainfall intensity, geology, and elevation to map flood hazard across the Koiliaris River Basin (KRB), Greece. The static GIS information of vegetation, topography, and soil can provide valuable information for locations with potential flooding risk. ...
Floods introduced by rainfall events are responsible for tremendous economic and property losses. It is important to delineate flood prone areas to minimize flood damages and make mitigation plans. Recently, there has been recognition of the need to understand the risk from groundwater flooding caused by the emergence of groundwater at the ground surface. Mapping groundwater flood risk is more challenging compared to river flooding, especially in karst systems, where subsurface preferential flowpaths can affect groundwater flow. We developed a coupled surface-subsurface modelling framework resolving spatial information and hydrologic data to assess the groundwater flood risk at a karstic watershed: Koiliaris River Basin, Greece. The simulated groundwater table was used to delineate groundwater flooding. Modelled results revealed the role of faults in groundwater flooding generation. We anticipate the coupled surface-subsurface approach to be a starting point for more sophisticated flooding risk assessment, including magnitude and temporal duration of groundwater flooding.
