ABSTRACT
Green computing is the current research hotspot; adapting the professional computing model to the low-power ARM architecture processor is a research trend. This article constructs a hydrological–hydrodynamic model by choosing SWMM and TELEMAC-2D as submodules, taking stormwater grates and inspection wells as water flow exchange nodes. The container technology was selected to couple the model on the ARM architecture processor, and the adapted coupling model is named the ARM hydrological–hydrodynamic model (AHM). To verify the reasonableness and accuracy of the model, taking the inner harbor of Macao Peninsula as the study area, a numerical simulation study on the evolution of waterlogging was carried out in various scenarios. The analysis showed that the maximum flow velocity was concentrated in the streets with low topography in the city center, and the areas of standing water were distributed in a point-like manner. Risk distribution maps during different storm recurrence periods were also constructed. Finally, the direct economic losses caused by Typhoon Mangkhut were calculated based on the model results and compared with the statistical values, with an error of only 2.3%, and the direct flooding losses in the inner harbor area under different rainfall scenarios were derived accordingly.
HIGHLIGHTS
A coupled urban hydrology and hydrodynamics model was constructed and adapted to a low-power ARM processor.
Numerical simulation studies on the evolution of waterlogging in Macao were carried out under various scenarios.
Risk distribution maps for the inner harbor area under different rainfall return periods were prepared, and flood-prone points were noted.
Predicting and projecting the direct loss of waterlogging in the inner harbor area under different rainfall scenarios.
INTRODUCTION
With the rapid urbanization process and global climate change, the extreme precipitation characteristics of urban areas have changed significantly, and intense rainstorms occur frequently, causing huge socioeconomic and life and property losses (Zhang et al. 2014; Alabbad et al. 2023; Li et al. 2023). Numerical simulation is an important method to study the formation mechanism and evolution law of urban flooding, through which the simulation can restore the rainfall, water conditions, and disaster-affected process of burdensome rainfall events and provide theoretical and technological references for the construction of urban flood prevention and disaster mitigation system (Zhou et al. 2012; Zang et al. 2020; Xu & Ye 2021; Luo et al. 2022; Alipour et al. 2023). It is worth mentioning that urban waterlogging is a real-world problem. Using different hydrological models to solve water problems will help achieve the UN's sustainable development goals and ensure that urban development is inclusive, safe, resilient, and sustainable (Mohammadi et al. 2024).
Urban areas are densely populated and property intensive. Once waterlogging occurs, it will cause huge losses. The construction of an urban waterlogging model can effectively reduce waterlogging losses. However, the irregular distribution of streets and buildings in urban areas results in very complex surface runoff. One-dimensional (1D) flow models cannot accurately describe the changes in subsurface water flow and the distribution of waterlogged areas, and two-dimensional (2D) surface flow models must be applied. At the same time, urban floods are usually discharged through streams that outlet from the source catchment, so the influence of urban drainage systems on surface runoff is significant (Bazin et al. 2014). However, early simplified models did not reflect the presence of subsurface drainage systems or the drainage systems are modeled as unidirectional (Ellis et al. 1982), which means that the drainage system does not allow water to return to the surface even when it exceeds its capacity. In extreme rainfall events, surface runoff is dominant, and simplified models also have high accuracy. However, the drainage system's presence in most cases will significantly impact the flooding simulation. Therefore, a large number of scholars have made an in-depth investigation into the construction of a 1D–2D coupled model. Leandro et al. (2009) adopted the concept of dual drainage, constructed a 1D/1D model and a 1D/2D model, and compared them, pointing out the problems that should be paid attention to in establishing the coupled model and the calibration. Seyoum et al. (2012) coupled the stormwater channel model SWMM5 and a 2D noninertial slope flow model in a two-dimensional coupled model. The inertial slope flow model is used to simulate the interaction between the sewerage system and the urban floodplain, and the ability model to simulate flooding was demonstrated through two case studies. Subsequently, Yu & Huang (2015) proposed a coupled one-dimensional (1D) and two-dimensional (2D) numerical model for the free-surface flow. Practical applications show that the model can accurately and effectively simulate the free-surface flow. To predict the extent of flood inundation more accurately, Leandro & Martins (2016) proposed a method to link the 2D overland flow model with the storm sewer model SWMM5 to achieve bidirectional interaction between the two models during simulation. Wu et al. (2017) established a two-dimensional hydrodynamic inundation model based on SWMM and LISFLOOD-FP models, revealing urban inundation's evolution under different storms, sea level rise, and subsidence scenarios. Zeng et al. (2019) and Chen et al. (2021) used SWMM as a one-dimensional computing module, combined with other two-dimensional computing modules to construct a coupled model of urban waterlogging, achieving high computational accuracy.
After years of research, many excellent coupled models for urban flooding have been developed. However, almost all of them are based on the X86 architecture processor. The X86 instruction set adopts the complex instruction set computer architecture, which makes the X86 processor costly to design and manufacture and is prone to design flaws and loopholes. The complexity of the instruction set also leads to lower efficiency, higher power consumption, and less flexibility in executing instructions, which can be limited in application scenarios such as embedded systems, mobile devices, and Internet-of-Things (IoT) devices (Blem et al. 2013; Kaiser et al. 2023). As the scale of cloud computing and cloud data centers continues to expand, large-scale, high-accuracy simulation of urban flooding is also gradually shifted to cloud computing platforms, and with it comes enormous energy consumption. In contrast, the Advanced RISC Machines (ARM) architecture has advantages such as high performance and low power consumption and is rapidly becoming the first choice for green computing. ARM architecture processors use a reduced instruction set computer (RISC) processor with a relatively small number of instructions that can be combined to achieve complex calculations and operations, increasing the speed at which instructions run and minimizing power consumption. Aroca & Gonalves (2012) compared parameters such as power consumption, CPU load, temperature, and floating point performance of applications on X86 and ARM computer architecture servers, showing that ARM-based servers are a good choice for green data centers. Yokoyama et al. (2019) analyzed the ARM architecture processors' improvement capabilities and the history of developing energy-efficient processors. They concluded that ARM would be a viable solution for tens of billions of power walls. Rico et al. (2017) have also tested the performance of supercomputers and high-performance computing applications (CP2K, GROMACS, NAMD, VASP, etc.) based on ARM instruction set compatible architecture processors. The results of the experiments show that ARM-based processors can provide performance levels that are competitive with the existing state-of-the-art X86 products, and ARM-based server CPUs optimized for High Performance Computing (HPC) can match the performance of comparable X86-based server CPUs. ARM-based servers optimized for HPC can match the performance of best-in-class CPUs while offering attractive price and performance advantages. To achieve the coupled model, ARM architecture adaptation needs to address the main compatibility issues so that the computing software can meet the functional requirements of professional computing but also needs to consider giving full play to the advantages of the ARM architecture of low power consumption while ensuring that the adapted model does not affect the host and other applications. Compared with x86 architecture, some ARM processors still have some limitations in performance. Especially when dealing with large amounts of data and complex calculations, it may not be able to compete with high-end x86 processors. However, with the development of technology and the improvement of the ecosystem, the limitations of ARM processors are gradually decreasing. Therefore, adapting the constructed coupling model to ARM architecture processing is also the highlight of this article (Blake et al. 2021; Jin et al. 2022).
In the simulation calculation of urban waterlogging, there are some limitations in the use of the hydrological model or hydrodynamic model alone. Hydrological models are usually used to predict rainwater runoff processes and lack a detailed description of urban characteristics, such as buildings, roads, and drainage systems. The hydrological models are usually based on natural processes while ignoring the impact of human drainage systems, which may lead to inaccurate predictions in urban waterlogging simulations. The limitation of the hydrodynamic model is that it requires a lot of computing resources and time, especially in the simulation of urban waterlogging; it is necessary to consider the large-scale complex urban terrain and water flow path. To reduce the amount of calculation, the hydrodynamic model may need to parameterize or simplify the urban characteristics, which may lead to a decrease in the accuracy of the simulation results.
Combining the aforementioned analyses, a coupled urban ARM hydrological–hydrodynamic model (AHM) is constructed in this article. The hydrological method simulates the rainfall production process, the slope confluence and surface inundation process are simulated by the two-dimensional hydrodynamic method, and the river and pipe network flow is simulated by the one-dimensional hydrodynamic method. The two models are synchronized to perform the computation and achieve the real-time exchange of computational data to carry out the bidirectional coupled simulation. To achieve the goal of green computing, the coupled model and its dependencies are packaged into a mirror file using container technology to make it adaptable to the ARM architecture. Taking the inner harbor of the Macao Peninsula as an example, numerical simulation studies on the evolution of waterlogging in the inner harbor area of Macao under various scenarios are carried out to analyze the weaknesses and significant problems in the prevention and control of waterlogging in the Macao area, to classify the risk level of the Macao area by combining the characteristics of the disaster-carrying body and the characteristics of the distribution of the GDP, to form the distribution map of the risk of the disaster, and to predict and deduce the direct loss of the flooding in the inner harbor area under different rainfall scenarios.
COUPLED MODEL CONSTRUCTION
The model in this article adopts the concept of dual drainage, with rain grates and catchment wells as nodes, to establish the link between the urban surface and the drainage network, and the construction of hydrological–hydrodynamic coupling model can improve the accuracy of urban flooding simulation, to effectively prevent and respond to urban flooding events. The current models that can realize one-dimensional and two-dimensional coupled simulation include MIKE 21, MIKE URBAN, InfoWorks ICM, etc. However, most are commercial paid software, while free, open-source research models are relatively scarce. Therefore, this study uses the open-source software SWMM and TELEMAC-2D as submodules to construct a coupled urban hydrological and hydrodynamic model.
SWMM model
One-dimensional hydrodynamic models are used to simulate water flow in urban drainage systems, rivers, and channels, including SWMM (Storm et al. Model), HEC-RAS (Hydrologic Engineering Center's River Analysis System), InfoWorks (Integrated Catchment Modeling), ICM (integrated catchment modeling), and so on. Among them, the SWMM model is adopted as the one-dimensional hydrodynamic module of the model due to its good stability and applicability, and the open-source code is conducive to the secondary development of the model, so the hydrological–hydrodynamic coupled model adopts the EXTRAN module of SWMM.
A one-dimensional hydrodynamic simulation of the governing equations based on the assumptions of the ‘pipe-node’ mechanism and the power wave equation is constructed, and due to the difficulty of obtaining an analytical solution of the equations, the EXTRAN module of SWMM uses a numerical solution method to solve the equations.
TELEMAC-2D model
TELEMAC software can construct 1D, 2D, and 3D hydrodynamic models to address wave propagation, water quality pollution, surface hydrology, sediment transport, and other issues. The 2D hydrodynamic module (TELEMAC-2D) has been widely used to simulate hydrodynamic processes in rivers, estuaries, coasts, and floodplains with good results (Pinel et al. 2019), and the code is open source and can be developed for secondary use. The TELEMAC-2D module adopts the SCS method to perform the rainfall production flow calculations for the simulation. This method is an empirical model developed in the United States based on rainfall and runoff data from small watersheds, which is suitable for analyzing the flow processes in small watersheds and is widely used in hydrological problems related to small watersheds. The model is well developed, easy to compute, and has shown good simulation results in studying data-poor regions.
Coupling model
The one-dimensional hydrodynamic module used for the coupled hydrological–hydrodynamic model is SWMM5.1, and the two-dimensional hydrodynamic module is the v7p2r3 version of the TELEMAC-2D module. Vertical nodal coupling is used for water exchange, and the basic weir flow and orifice flow equations are used to calculate overflow and return flows. The equations are as follows.
ARM hydrodynamic model
In this study, Docker cross-platform construction image technology is adopted to build a Docker container image with a hydrological–hydrodynamic coupling model as the core, and the coupled model is adapted. The TELEMAC-2D and SWMM source codes are compiled, and the runtime environment is set up in the Dockerfile to build a container image containing the coupled model and the related runtime environment to run independently on the ARM architecture processing. The hardware and software test environments and adaptation conditions used in this study are presented in Table 1.
Category . | Project . | Requirement . |
---|---|---|
Hardware | Server | TaiShan 200 |
CPU | Kunpeng 920 | |
Network Card | TM210 | |
Software | Operating System | Centos7.6 |
Category . | Project . | Requirement . |
---|---|---|
Hardware | Server | TaiShan 200 |
CPU | Kunpeng 920 | |
Network Card | TM210 | |
Software | Operating System | Centos7.6 |
COMPUTATIONAL MODEL CONSTRUCTION
Selection of study area
Computational model construction
In this study, to consider the study area's water-blocking effect, the building elevation is superimposed on the original DEM data. To ensure the continuity of the building contour, this study adopts the way of dividing the grid for the noninterpolated value-taking method, the grid resolution is 3 m irregular triangular mesh, and the processed mesh has a total of 497,498 mesh nodes and 989,313 triangular meshes.
Different soil types have different infiltration rates and water retention capacities (CN values), which directly affect rainwater's infiltration and runoff process. Due to the small study area, the hydrological grouping of soil is only C and D. The different land use CN values of each soil type are taken as shown in Table 2. The type was obtained from the Macao Cadastral Bureau. The CN value was comprehensively considered by referring to the CN value table of the TR-55 manual of the United States Soil Protection Bureau and the research of relevant scholars, combined with soil types and land use classification (Cronshey et al. 1985; Liu et al. 2019).
CN . | C . | D . |
---|---|---|
Green space | 71 | 80 |
Roads | 94 | 98 |
Buildings | 96 | 98 |
Mountain | 79 | 84 |
Water | 100 | 100 |
Other | 88 | 92 |
CN . | C . | D . |
---|---|---|
Green space | 71 | 80 |
Roads | 94 | 98 |
Buildings | 96 | 98 |
Mountain | 79 | 84 |
Water | 100 | 100 |
Other | 88 | 92 |
Land use type . | Manning's coefficient . |
---|---|
Green space | 0.15 |
Roads | 0.012 |
Buildings | 0.012 |
Mountain | 0.4 |
Water | 0.015 |
Other | 0.05 |
Land use type . | Manning's coefficient . |
---|---|
Green space | 0.15 |
Roads | 0.012 |
Buildings | 0.012 |
Mountain | 0.4 |
Water | 0.015 |
Other | 0.05 |
AHM validation
Return period . | a . | b . |
---|---|---|
2 | 390.29 | −0.457 |
5 | 412.82 | −0.499 |
10 | 434.72 | −0.388 |
20 | 457.88 | −0.372 |
50 | 490.78 | −0.357 |
100 | 516.25 | −0.347 |
Return period . | a . | b . |
---|---|---|
2 | 390.29 | −0.457 |
5 | 412.82 | −0.499 |
10 | 434.72 | −0.388 |
20 | 457.88 | −0.372 |
50 | 490.78 | −0.357 |
100 | 516.25 | −0.347 |
ANALYSIS OF RESULTS
Flood risk assessment
The main factors contributing to flood damage are indicators such as flood velocity and depth of standing water. Under extremely heavy rainfall conditions, there is a high risk of street flooding currents, significantly affecting the flow of vehicles and people traveling to and from the area. Therefore, this article analyzes the street flow velocity data for the inner harbor area of the Macau Peninsula under different design storm conditions and the depth of standing water in the study area.
Risk level distribution
Based on the model calculation results, the study area is divided into several levels and plotted into a visual risk zoning map, which can provide a scientific basis for the decision-making of the flood control and drainage departments. Considering the data accuracy, scale size, and data distribution characteristics, the risk zoning classes selected for this study are divided into six levels, as shown in Table 5. These are low risk (<0.1 m), medium to low risk (0.1–0.3 m), medium risk (0.3–0.5 m), medium to high risk (0.5–1.0 m), high risk (1.0–1.5 m), and very high risk (>1.5 m).
Degree . | 1 . | 2 . | 3 . | 4 . | 5 . | 6 . |
---|---|---|---|---|---|---|
Risk | Low | Medium–low | Medium | Medium–high | High | Very high |
Water depth | <0.1 m | 0.1–0.3 m | 0.3–0.5 m | 0.5–1.0 m | 1.0–1.5 m | >1.5 m |
Degree . | 1 . | 2 . | 3 . | 4 . | 5 . | 6 . |
---|---|---|---|---|---|---|
Risk | Low | Medium–low | Medium | Medium–high | High | Very high |
Water depth | <0.1 m | 0.1–0.3 m | 0.3–0.5 m | 0.5–1.0 m | 1.0–1.5 m | >1.5 m |
Waterlogging solutions
According to the analysis of the model calculation results, the relevant measures taken include engineering and nonengineering measures to reduce the risk of waterlogging in Macao. The engineering measures include optimizing and upgrading the drainage system in the waterlogging area, accelerating the discharge of rainwater and reducing the occurrence of waterlogging. It also includes building, expanding, or transforming water conservancy projects; reasonably setting rainwater collection ponds, green spaces, and wetlands; and increasing city's ability to resist waterlogging risks; nonengineering measures include establishing a sound meteorological monitoring and flood warning system, timely monitoring of weather changes and water conditions, and issuing early warning information to the public to take countermeasures. It also includes establishing and improving the emergency management mechanism, emergency rescue ability, and personnel training level to ensure they can quickly and effectively respond to and rescue during waterlogging disasters.
Calculation of flood losses
. | GDP . | Proportion (%) . | . | GDP . | Proportion (%) . |
---|---|---|---|---|---|
Manufacturing | 2,053 | 0.8 | Insurance and Pension Funds | 10,171 | 4.1 |
Electricity, water and gas production and supply | 2,772 | 1.1 | Real Estate | 32,201 | 13.1 |
Construction | 14,230 | 5.8 | Rental and Business Services | 11,375 | 4.6 |
Wholesale and retail trade | 21,555 | 8.8 | Public Administration | 19,830 | 8.1 |
Hospitality | 7,211 | 2.9 | Education | 9,123 | 3.7 |
Catering | 3,923 | 1.6 | Healthcare & Social Welfare | 7,458 | 3.0 |
Transport, storage and communications | 6,660 | 2.7 | Gaming and Gaming Intermediation | 63,420 | 25.8 |
Banking | 25,732 | 11.3 | Other services | 6,158 | 2.5 |
. | GDP . | Proportion (%) . | . | GDP . | Proportion (%) . |
---|---|---|---|---|---|
Manufacturing | 2,053 | 0.8 | Insurance and Pension Funds | 10,171 | 4.1 |
Electricity, water and gas production and supply | 2,772 | 1.1 | Real Estate | 32,201 | 13.1 |
Construction | 14,230 | 5.8 | Rental and Business Services | 11,375 | 4.6 |
Wholesale and retail trade | 21,555 | 8.8 | Public Administration | 19,830 | 8.1 |
Hospitality | 7,211 | 2.9 | Education | 9,123 | 3.7 |
Catering | 3,923 | 1.6 | Healthcare & Social Welfare | 7,458 | 3.0 |
Transport, storage and communications | 6,660 | 2.7 | Gaming and Gaming Intermediation | 63,420 | 25.8 |
Banking | 25,732 | 11.3 | Other services | 6,158 | 2.5 |
Direct economic losses are calculated using the loss rate method. Lv et al. (2021) determined the relationship between the depth of inundation and the loss rate for different land use types. Based on the cumulative inundation depth combined with the disaster damage curves of different land use types under different inundation depths can be calculated to obtain the corresponding loss amount. The Macao region is mainly dominated by commercial land use, residential land use, industrial land use, and public service land use. Table 7 shows the data obtained based on the flood loss rate function for the four land types.
Land use type . | Depth of inundation (m) . | |||||||
---|---|---|---|---|---|---|---|---|
< 0.1 . | 0.1–0.3 . | 0.3–0.5 . | 0.5–1.0 . | 1.0–1.5 . | 1.5–2.0 . | 2.0–3.0 . | > 3.0 . | |
Commercial | 0.009 | 0.020 | 0.05 | 0.09 | 0..15 | 0.20 | 0.26 | 0.28 |
Residential | 0.008 | 0.015 | 0.04 | 0.08 | 0.14 | 0.18 | 0.24 | 0.27 |
Industrial | 0.006 | 0.012 | 0.03 | 0.06 | 0.11 | 0.17 | 0.21 | 0.25 |
Public services | 0.005 | 0.010 | 0.02 | 0.05 | 0.10 | 0.16 | 0.20 | 0.24 |
Land use type . | Depth of inundation (m) . | |||||||
---|---|---|---|---|---|---|---|---|
< 0.1 . | 0.1–0.3 . | 0.3–0.5 . | 0.5–1.0 . | 1.0–1.5 . | 1.5–2.0 . | 2.0–3.0 . | > 3.0 . | |
Commercial | 0.009 | 0.020 | 0.05 | 0.09 | 0..15 | 0.20 | 0.26 | 0.28 |
Residential | 0.008 | 0.015 | 0.04 | 0.08 | 0.14 | 0.18 | 0.24 | 0.27 |
Industrial | 0.006 | 0.012 | 0.03 | 0.06 | 0.11 | 0.17 | 0.21 | 0.25 |
Public services | 0.005 | 0.010 | 0.02 | 0.05 | 0.10 | 0.16 | 0.20 | 0.24 |
According to the different land use types, the GDP is reasonably distributed, the GDP data are gridded, and the specific loss value of the flood disaster can be calculated by combining the grid data of the inundation depth in the study area with the disaster damage curve. In this study, the spatial distribution of the depth of inundation simulated by AHM is superimposed on the spatial distribution data of GDP to find the direct economic losses at different moments. First, the direct economic loss caused by typhoon Mangosteen in Macau is calculated based on the constructed model using typhoon Mangosteen as an example. The direct economic losses caused by Typhoon Mangosteen are summarized in Table 8.
Estimated projects . | Direct losses (MOP billion) . |
---|---|
(a) Wholesale, retail and foodstuffs | 2.49 |
(b) Construction | 0.94 |
(c) Hospitality | 1.12 |
(d) Finance | 0.19 |
(e) Gaming | – |
(f) Other industries | 0.10 |
(g) Residential and vehicle | 0.03 |
(h) Public facilities and government departments | 0.30 |
Total | 5.17 |
Estimated projects . | Direct losses (MOP billion) . |
---|---|
(a) Wholesale, retail and foodstuffs | 2.49 |
(b) Construction | 0.94 |
(c) Hospitality | 1.12 |
(d) Finance | 0.19 |
(e) Gaming | – |
(f) Other industries | 0.10 |
(g) Residential and vehicle | 0.03 |
(h) Public facilities and government departments | 0.30 |
Total | 5.17 |
The moment of maximum water accumulation (13 h) is selected for direct flooding loss calculation, and the mean GDP number is assigned to the calculation grid based on the distribution of different industries and the total value of GDP per unit area in 2018, with a maximum calculation grid area of 9 m2, then superimposed on the depth of water accumulation in each grid of the calculation area, and the loss calculation is carried out based on the flooding loss rate function for different land use types. The direct economic loss at the moment of maximum waterlogging for the rainfall of Typhoon Mangkhut is calculated to be MOP 344 million. Since the total GDP value of the study area accounts for 65% of the total GDP of the Macao region, the direct economic loss caused by typhoon Mangosteen to the study area is MOP 336 million. The error between the results calculated by this model and the statistical value of the Macao region is 2.3%.
CONCLUSION
To achieve the purpose of green computing, a coupled urban hydrological–hydrodynamic model is constructed, and the coupled model is adapted to the ARM architecture processor (AHM). To verify the rationality of the model and the accuracy of the results, the inner harbor of Macao Peninsula is taken as the study area, and the evolution of flooding in the inner harbor area of Macao is analyzed based on the AHM model under different rainfall scenarios. The following conclusions are drawn:
- (1)
The AHM can perform urban flooding calculations on the ARM architecture processor, and the results show that the rainfall pattern of the change of the total amount of standing water in different rainfall recurrence periods is consistent. The measured water depth changes and simulation results of Kang Kung Temple and Lower Ring rainfall stations are compared, and the Nash efficiency coefficients are 0.91 and 0.87, respectively, which indicates that the AHM has reasonableness and accuracy. From the calculation results, we can obtain the flow velocity trends, water depth, waterlogged area, and volume during the rainfall recurrence period, which provides technical support for constructing the dynamic assessment model of waterlogging.
- (2)
The rainfall velocities of 2a, 5a, and 10a ranged from 0.6 to 0.9 m/s and are mainly concentrated in the coastal neighborhoods. In contrast, the maximum velocities of 20a, 50a, and 100a reached more than 1.0 m/s, and most are concentrated in the low-lying streets in the city center. The changes in road water accumulation and flow velocity will affect rescue efficiency and indirectly increase the flood damage in Macao. In this article, the distribution maps of road flow velocity and water accumulation can provide theoretical references for rational planning rescue routes in the inner harbor area and reducing flood damage.
- (3)
The waterlogging in the study area is distributed pointwise, with water depths ranging from 0.1 to 0.5 m in most centers. The area of flooded points with a water depth of more than 1.0 m is 6.81 × 10−4km2, which is only 0.068% of the study area. In this study, the inundation points are also screened, and those with inundation water depths exceeding 1.0 m are marked and labeled. The inundation water depth data are also overlaid with the industry distribution data in Macau to form a map of the distribution of flooding risk levels in the study area. The results show that when the rainfall intensity exceeds once in 10 years, the drainage capacity of the Macao area is well overloaded and the risk of flooding increases significantly.
- (4)
Taking Typhoon Mangkhut as an example, the specific damage value of Mangosteen is calculated to be MOP 344 million by combining the grid data of inundation depth and the disaster damage curve of the study area. The error with the statistical value for the Macau area is 2.3%. To analyze the changes in inundation loss during rainfall, it provides a reference for the direct economic loss of inundation in the Macao region. Rainfalls of different recurrence periods are analyzed, and one scenario is selected every 10 min to obtain the change curve of inundation direct loss of internal flooding. Meanwhile, combined with the change in GDP, the flooding loss of Macau in different years can be deduced according to the change rule of inundation loss in this article.
The AHM in this article only applies to serial computing, and improving the AHM to enable parallel computing and GPU-accelerated computing is the current direction of model improvement. At the same time, the coupled model can be adapted to ARM architecture to improve its computational performance. However, the specific performance enhancement value needs to be further studied and evaluated, which will be the focus of the subsequent research.
ACKNOWLEDGEMENTS
This work was supported by Chinese National Key Research and Development Program (No. 2022YFE0205200 & 2022YFC3090600), the National Natural Science Foundation of China (No. 52192671), IWHR Research & Development Support Program (WR110145B0022022), the Research Fund of the State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin (No. SKL2022TS11), and the Open Research Fund of Key Laboratory of River Basin Digital Twinning of Ministry of Water Resources.
CREDIT AUTHOR STATEMENT
Haijia Zhang: conceptualization, validation, formal analysis, investigation, and writing – original draft; Jiahong Liu: conceptualization, software, writing – review and editing, and resources; Chao Mei: conceptualization, writing – review and editing, and resources; Lirong Dong: conceptualization, writing – review and editing, and project administration. Tianxu Song: conceptualization, writing – review and editing, and project administration.
DATA AVAILABILITY STATEMENT
Data cannot be made publicly available; readers should contact the corresponding author for details.
CONFLICT OF INTEREST
The authors declare there is no conflict.