The paper investigates compound flooding from waves, sea surge and river flow in northern Jakarta... more The paper investigates compound flooding from waves, sea surge and river flow in northern Jakarta, Indonesia, which is a global hotspot of flooding, by combining process-based coastal and river models. The coastal hydrodynamic modelling of Jakarta Bay in Indonesia shows that coastal storms can lead to a substantial increase in sea water level due to wind and wave setup in the nearshore areas, including Muara Angke river inlet. The compound flood hazard from a range of flood scenarios was simulated and analysed. The results reveal that low-lying areas around the river inlet are prone to flooding even during regular, low-intensity storm events, while rarer storms caused extensive floods. Floods were not caused by direct overwashing of sea defences but by overspill of the banks of the river inlet due to high sea water level caused by wind set up, wave setup, and sea surge obstructing the drainage of the river and elevating its water level during storms. We also found that the sea level...
Complicated model structure and time consuming simulations increase the use of models in decision... more Complicated model structure and time consuming simulations increase the use of models in decision making process when the stakeholders are not familiar with the tools. Therefore, the user interface (UI) design for decision support system (DSS) should not only maintain the scientific model structure but also simplify the interaction with models and the need for easy access. Nowadays, web-based techniques have been developed so fast and Web 2.0 brings the time when web-based systems challenge the desktop applications. This technology also needs to be taken into account in the DSS development for water resource management because the stakeholders are spatial distributed and the internet is the most commonly available resource. In this paper, we developed a WebDSS prototype named VisREACHER that is fully based on Free and Open Source Software (FOSS). It is a stand-alone web page with the decision model running behind which means it offers more than a visualization system of a prepared d...
<p><span>This two-year trial aims to bring together academics and ind... more <p><span>This two-year trial aims to bring together academics and industrial partners from UK and China to conduct a pilot study on the use of the active phased array radar to provide early urban flood warnings for Chinese mega cities, which facing challenging urban flood issues. This is the first in the world of cascade modelling using the cutting-edge active phase array radar (APRA) to provide rainfall monitoring and nowcasting information for a real-time two-dimension urban drainage model. The collaboration built up by this project and the first-hand experiment data will serve well to further catalyse the taking-up of state-of-the-art weather radars for urban flood risk management, and to tackle the innovation in tuning the radar technology to fit the complex urban environment as well as advanced modelling facilities that are designed to link the observations, providing decision making support to the city government. Recommendations for applying high spatial-temporal resolution precipitation data to real-time flood forecasting on an urban catchment are provided and suggestions for further investigation are discussed.</span></p>
<p> Flooding is widely regarded as one of the most dangerous natural h... more <p> Flooding is widely regarded as one of the most dangerous natural hazards worldwide. It often arises from various sources either individually or combined such as extreme rainfall, storm surge, high sea level, large river discharge or the combination of them. However, the concurrence or close succession of these different source mechanisms can lead to compound flooding, resulting in larger damages and even catastrophic consequences than those from the events caused by the individual mechanism. Here, we present a modelling framework aimed at supporting risk analysis of compound flooding in the context of climate change, where nonstationary joint probability of multiple variables and their interactions need to be quantified.The framework uses the Block Bootstrapping Mann-Kendall test to detect the temporal changes of marginals, and the correlation test associated with the Rolling Window method to estimate whether the correlation structure varies with time; it then evaluates various combinations of marginals and copulas under stationary and nonstationary assumptions. Meanwhile, a Bayesian Markov Chain Monte Carlo method is employed to estimate the time-varying parameters of copulas. </p>
In this article, we present the use of the coupled land surface model and groundwater flow model ... more In this article, we present the use of the coupled land surface model and groundwater flow model SWAT-MODFLOW with the decision support tool WEAP (Water Evaluation and Planning software) to predict future surface water abstraction scenarios in a complex river basin, under conditions of climate change. The modeling framework is applied to the Dee River catchment in Wales, United Kingdom. Regarding hydrology, the coupled model improves overall water balance and low streamflow conditions, compared to a stand-alone SWAT model. The calibrated SWAT-MODFLOW is employed with high resolution climate model data from the UKCP18 project with future scenario of RCP85 from 2020 to 2040. Then, water supply results from SWAT-MODFLOW are fed into WEAP as input for the river reach in the downstream region of the river basin. This system is utilized to create various future scenarios of surface water abstraction of public water supply in the downstream region: maximum licensed withdraw, 50 % authorize...
The paper investigates compound flooding from waves, sea surge and river flow in northern Jakarta... more The paper investigates compound flooding from waves, sea surge and river flow in northern Jakarta, Indonesia, which is a global hotspot of flooding, by combining process-based coastal and river models. The coastal hydrodynamic modelling of Jakarta Bay in Indonesia shows that coastal storms can lead to a substantial increase in sea water level due to wind and wave setup in the nearshore areas, including Muara Angke river inlet. The compound flood hazard from a range of flood scenarios was simulated and analysed. The results reveal that low-lying areas around the river inlet are prone to flooding even during regular, low-intensity storm events, while rarer storms caused extensive floods. Floods were not caused by direct overwashing of sea defences but by overspill of the banks of the river inlet due to high sea water level caused by wind set up, wave setup, and sea surge obstructing the drainage of the river and elevating its water level during storms. We also found that the sea level...
Complicated model structure and time consuming simulations increase the use of models in decision... more Complicated model structure and time consuming simulations increase the use of models in decision making process when the stakeholders are not familiar with the tools. Therefore, the user interface (UI) design for decision support system (DSS) should not only maintain the scientific model structure but also simplify the interaction with models and the need for easy access. Nowadays, web-based techniques have been developed so fast and Web 2.0 brings the time when web-based systems challenge the desktop applications. This technology also needs to be taken into account in the DSS development for water resource management because the stakeholders are spatial distributed and the internet is the most commonly available resource. In this paper, we developed a WebDSS prototype named VisREACHER that is fully based on Free and Open Source Software (FOSS). It is a stand-alone web page with the decision model running behind which means it offers more than a visualization system of a prepared d...
<p><span>This two-year trial aims to bring together academics and ind... more <p><span>This two-year trial aims to bring together academics and industrial partners from UK and China to conduct a pilot study on the use of the active phased array radar to provide early urban flood warnings for Chinese mega cities, which facing challenging urban flood issues. This is the first in the world of cascade modelling using the cutting-edge active phase array radar (APRA) to provide rainfall monitoring and nowcasting information for a real-time two-dimension urban drainage model. The collaboration built up by this project and the first-hand experiment data will serve well to further catalyse the taking-up of state-of-the-art weather radars for urban flood risk management, and to tackle the innovation in tuning the radar technology to fit the complex urban environment as well as advanced modelling facilities that are designed to link the observations, providing decision making support to the city government. Recommendations for applying high spatial-temporal resolution precipitation data to real-time flood forecasting on an urban catchment are provided and suggestions for further investigation are discussed.</span></p>
<p> Flooding is widely regarded as one of the most dangerous natural h... more <p> Flooding is widely regarded as one of the most dangerous natural hazards worldwide. It often arises from various sources either individually or combined such as extreme rainfall, storm surge, high sea level, large river discharge or the combination of them. However, the concurrence or close succession of these different source mechanisms can lead to compound flooding, resulting in larger damages and even catastrophic consequences than those from the events caused by the individual mechanism. Here, we present a modelling framework aimed at supporting risk analysis of compound flooding in the context of climate change, where nonstationary joint probability of multiple variables and their interactions need to be quantified.The framework uses the Block Bootstrapping Mann-Kendall test to detect the temporal changes of marginals, and the correlation test associated with the Rolling Window method to estimate whether the correlation structure varies with time; it then evaluates various combinations of marginals and copulas under stationary and nonstationary assumptions. Meanwhile, a Bayesian Markov Chain Monte Carlo method is employed to estimate the time-varying parameters of copulas. </p>
In this article, we present the use of the coupled land surface model and groundwater flow model ... more In this article, we present the use of the coupled land surface model and groundwater flow model SWAT-MODFLOW with the decision support tool WEAP (Water Evaluation and Planning software) to predict future surface water abstraction scenarios in a complex river basin, under conditions of climate change. The modeling framework is applied to the Dee River catchment in Wales, United Kingdom. Regarding hydrology, the coupled model improves overall water balance and low streamflow conditions, compared to a stand-alone SWAT model. The calibrated SWAT-MODFLOW is employed with high resolution climate model data from the UKCP18 project with future scenario of RCP85 from 2020 to 2040. Then, water supply results from SWAT-MODFLOW are fed into WEAP as input for the river reach in the downstream region of the river basin. This system is utilized to create various future scenarios of surface water abstraction of public water supply in the downstream region: maximum licensed withdraw, 50 % authorize...
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