Assessing the Potential Highest Storm Tide Hazard in Taiwan Based on 40-Year Historical Typhoon Surge Hindcasting

Typhoon-induced storm surges are catastrophic disasters in coastal areas worldwide, although typhoon surges are not extremely high in Taiwan. However, the rising water level around an estuary could be a block that obstructs the flow of water away from the estuary and indirectly forms an overflow in the middle or lower reaches of a river if the occurrence of the highest storm surge (HSS) coincides with the highest astronomical tide (HAT). Therefore, assessing the highest storm tide (HST, a combination of the HSS and HAT) hazard level along the coast of Taiwan is particularly important to an early warning of riverine inundation. This study hindcasted the storm surges of 122 historical typhoon events from 1979 to 2018 using a high-resolution, unstructured-grid, surge-wave fully coupled model and a hybrid typhoon wind model. The long-term recording measurements at 28 tide-measuring stations around Taiwan were used to analyze the HAT characteristics. The hindcasted HSSs of each typhoon category (the Central Weather Bureau of Taiwan classified typhoon events into nine categories according to the typhoon’s track) were extracted and superposed on the HATs to produce the individual potential HST hazard maps. Each map was classified into six hazard levels (I to VI). Finally, a comprehensive potential HST hazard map was created based on the superposition of the HSSs from 122 typhoon events and HATs.

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The Double-ITCZ Bias in CMIP6 Models

10.5194/egusphere-egu2020-21375 ◽

2020 ◽

Author(s):

Baijun Tian

Keyword(s):

Climate Models ◽

Global Climate ◽

Coupled Model ◽

Global Climate Models ◽

Cmip5 Models ◽

Tropical Precipitation ◽

Double Itcz ◽

Intercomparison Project ◽

Fully Coupled

<p>The double-Intertropical Convergence Zone (ITCZ) bias is one of the most outstanding problems in climate models. This study seeks to examine the double-ITCZ bias in the latest state-of-the-art fully coupled global climate models that participated in Coupled Model Intercomparison Project (CMIP) Phase 6 (CMIP6) in comparison to their previous generations (CMIP3 and CMIP5 models). To that end, we have analyzed the long-term annual mean tropical precipitation distributions and several precipitation bias indices that quantify the double-ITCZ biases in 75 climate models including 24 CMIP3 models, 25 CMIP3 models, and 26 CMIP6 models. We find that the double-ITCZ bias and its big inter-model spread persist in CMIP6 models but the double-ITCZ bias is slightly reduced from CMIP3 or CMIP5 models to CMIP6 models.</p>

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TIME-VARYING EMULATOR FOR SHORT- AND LONG-TERM ANALYSIS OF COASTAL FLOODING (TESLA-FLOOD)

Coastal Engineering Proceedings ◽

10.9753/icce.v36.currents.4 ◽

2018 ◽

pp. 4

Author(s):

Dylan Anderson ◽

Peter Ruggiero ◽

Fernando J. Mendez ◽

Ana Rueda ◽

Jose A. Antolinez ◽

...

Keyword(s):

Sea Level ◽

Storm Surges ◽

Coastal Flooding ◽

Water Levels ◽

Sea Level Anomalies ◽

Extreme Water Levels ◽

Flooding Risk ◽

The Individual ◽

Flooding Events

The ability to predict coastal flooding events and associated impacts has emerged as a primary societal need within the context of projected sea level rise (SLR) and climate change. The duration and extent of flooding is the result of nonlinear interactions between multiple environmental forcings (oceanographic, meteorological, hydrological) acting at varying spatial (local to global) and temporal scales (hours to centuries). Individual components contributing to total water levels (TWLs) include astronomical tides, monthly sea level anomalies, storm surges, and wave setup. Common practices often use the observational record of extreme water levels to estimate return levels of future extremes. However, such projections often do not account for the individual contribution of processes resulting in compound TWL events, nor do they account for time-dependent probabilities due to seasonal, interannual, and long-term oscillations within the climate system. More robust estimates of coastal flooding risk require the computation of joint probabilities and the simulation of hypothetical TWLs to better constrain the projection of extremes (Serafin [2014]).

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Hazard Assessment of Typhoon-Driven Storm Waves in the Nearshore Waters of Taiwan

Water ◽

10.3390/w10070926 ◽

2018 ◽

Vol 10 (7) ◽

pp. 926 ◽

Cited By ~ 8

Author(s):

Chih-Hsin Chang ◽

Hung-Ju Shih ◽

Wei-Bo Chen ◽

Wen-Ray Su ◽

Lee-Yaw Lin ◽

...

Keyword(s):

Human Life ◽

Coupled Model ◽

Storm Surges ◽

Coastal Zones ◽

Wind Fields ◽

Storm Waves ◽

Storm Wave ◽

Wave Heights ◽

Hazard Level ◽

Hazard Levels

In Taiwan, the coastal hazard from typhoon-induced storm waves poses a greater threat to human life and infrastructure than storm surges. Therefore, there has been increased interest in assessing the storm wave hazard levels for the nearshore waters of Taiwan. This study hindcasted the significant wave heights (SWHs) of 124 historical typhoon events from 1978 to 2017 using a fully coupled model and hybrid wind fields (a combination of the parametric typhoon model and reanalysis products). The maximum SWHs of each typhoon category were extracted to create individual storm wave hazard maps for the sea areas of the coastal zones (SACZs) in Taiwan. Each map was classified into five hazard levels (I to V) and used to generate a comprehensive storm wave hazard map. The results demonstrate that the northern and eastern nearshore waters of Taiwan are threatened by a hazard level IV (SWHs ranging from 9.0 to 12.0 m) over a SACZ of 510.0 km2 and a hazard level V (SWHs exceeding 12.0 m) over a SACZ of 2152.3 km2. The SACZs threatened by hazard levels I (SWHs less than 3.0 m), II (SWHs ranging from 3.0 to 6.0 m), and III (SWHs ranging from 6.0–9.0 m) are of 1045.2 km2, 1793.9 km2, and 616.1 km2, respectively, and are located in the western waters of Taiwan.

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Designing the Adaptive Landscape: Leapfrogging Stacked Vulnerabilities

Land ◽

10.3390/land10020158 ◽

2021 ◽

Vol 10 (2) ◽

pp. 158

Author(s):

Rob Roggema ◽

Nico Tillie ◽

Matthijs Hollanders

Keyword(s):

Climate Adaptation ◽

Dynamic Equilibrium ◽

Storm Surges ◽

Ground Level ◽

Climate Impacts ◽

Adaptive Landscape ◽

Short Term ◽

New Perspective ◽

The Individual

In the Anthropocene, climate impacts are expected to fundamentally change the way we live in, and plan and design for, our cities and landscapes. Long-term change and uncertainty require a long view, while current planning approaches and policy making are mostly short-term oriented and are therefore not well suited to respond adequately. The path-dependency it implies causes an irresolvable dilemma between short-term effect and long-term necessities. The objective of the research is to investigate an alternative planning and design approach which is able to overcome the current constraints and take a holistic long-term perspective. Therefore, the methods used in the study underpin a creative process of future visioning through backcasting and finding a dynamic equilibrium in the past as a primer for long-term climate adaptation. This way, the individual vulnerabilities of current sectoral policies can be leapfrogged and integrated into one intervention. This design-led method is applied to the northern landscape of the Groningen region in The Netherlands. This intervention is positioned as a re-dynamization of the landscape by re-establishing the exchange between the land and the sea. The findings in the study show that a long-term perspective on the future of the regional landscape increases climate adaptation and enriches the opportunities for viable agriculture, increased biodiversity, and a raised land that is not only protected against possible storm surges, but benefits from the sediments the sea brings. The economic analysis shows that a new perspective for farming within saline conditions is profitable on a fraction of the land, the biodiversity can be enriched by more than 75%, and the ground level of the landscape can be raised by one meter or more in the next 50–100 years. Moreover, the study shows how a long-term perspective can be implemented in logic stages that comply with the natural step-changes occurring in climate change.

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Simulation of Floating Debris in Violent Shallow Flows

10.29007/xw2s ◽

2018 ◽

Author(s):

Yan Xiong ◽

Samantha Mahaffey ◽

Qiuhua Liang

Keyword(s):

Laboratory Experiments ◽

Coupled Model ◽

Storm Surges ◽

Element Model ◽

Shock Capturing ◽

Hydrodynamic Characteristics ◽

Experimental Measurements ◽

Shallow Flows ◽

Complex Fluid ◽

Fully Coupled

Storm surge and tsunami may induce violent shallow flows and carry dense debris, causing tremendous damage to human lives, buildings and structures. This work presents a series of laboratory experiments to investigate the debris movement in the extreme flows. Subsequently, a new modeling tool featured with a finite volume shock-capturing hydrodynamic model fully coupled with a discrete element model is introduced. A new coupling method totally depending on the hydrodynamic characteristics is proposed to simulate the complex debris-enriched floods induced by tsunamis or storm surges. The experimental measurements are used to validate the reliability of the coupled model. The numerical results agree satisfactorily with the experimental measurements, demonstrating the model’s capability in simulating the complex fluid-debris interactions induced by violent shallow flows.

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A Fully Coupled Hydromechanical Model for CO2 Sequestration in Coal Seam: the Roles of Multiphase Flow and Gas Dynamic Diffusion on Fluid Transfer and Coal Behavior

Geofluids ◽

10.1155/2020/8871614 ◽

2020 ◽

Vol 2020 ◽

pp. 1-14

Author(s):

Rui Yang ◽

Weiqun Liu ◽

Tianran Ma ◽

Junhe Xie ◽

Yang Hu ◽

...

Keyword(s):

Coal Seam ◽

Multiphase Flow ◽

Coupled Model ◽

Gas Dynamic ◽

Fluid Transfer ◽

The Impact ◽

Fully Coupled ◽

Dynamic Diffusion ◽

Hydromechanical Model

CO2 sequestration in coal seam has proved to be an effective way for reducing air pollution caused by greenhouse gases. A study on the rules of fluid transfer and reliability of CO2 storage during gas injection is necessary for the engineering application. However, the clarification of multifield coupling in long-term CO2 sequestration is the difficulty to solve the aforementioned problem. Previous investigations on the coupled model for CO2 storage in coal seam were not exactly comprehensive; for example, the multiphase flow in the fracture and the nonlinear behavior of gas diffusion were generally neglected. In this paper, a new multistage pore model of the coal matrix and the corresponding dynamic diffusion model were adopted. Meanwhile, the CO2-induced coal softening and the CO2-water two-phase flow in coal fracture were also taken into account. Subsequently, all the mentioned mechanisms and interactions were embedded into the coupled hydromechanical model, and this new fully coupled model was well verified by a set of experimental data. Additionally, through the model application for long-term CO2 sequestration, we found that the stored CO2 molecules are mainly in an adsorbed state at the early injection stage, while with the continuous injection of gas, the stored CO2 molecules are mainly in a free state. Finally, the roles of multiphase flow and gas dynamic diffusion on fluid transfer and coal behavior were analyzed. The results showed that the impact of multiphase flow is principally embodied in the area adjacent to the injection well and the coal seam with lower initial water saturation is more reliable for CO2 sequestration, while the impact of gas dynamic diffusion is principally embodied in the area far away from the injection well, and it is safer for CO2 sequestration in coal seam with greater attenuation coefficient of CO2 diffusion.

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LICOM Model Datasets for the CMIP6 Ocean Model Intercomparison Project

Advances in Atmospheric Sciences ◽

10.1007/s00376-019-9208-5 ◽

2020 ◽

Vol 37 (3) ◽

pp. 239-249 ◽

Cited By ~ 11

Author(s):

Pengfei Lin ◽

Zhipeng Yu ◽

Hailong Liu ◽

Yongqiang Yu ◽

Yiwen Li ◽

...

Keyword(s):

Coupled Model ◽

Reanalysis Data ◽

Ocean Model ◽

Model Intercomparison ◽

Surface Data ◽

Intercomparison Project ◽

System Bias ◽

The Mean ◽

Fully Coupled

Abstract The datasets of two Ocean Model Intercomparison Project (OMIP) simulation experiments from the LASG/IAP Climate Ocean Model, version 3 (LICOM3), forced by two different sets of atmospheric surface data, are described in this paper. The experiment forced by CORE-II (Co-ordinated Ocean–Ice Reference Experiments, Phase II) data (1948–2009) is called OMIP1, and that forced by JRA55-do (surface dataset for driving ocean–sea-ice models based on Japanese 55-year atmospheric reanalysis) data (1958–2018) is called OMIP2. First, the improvement of LICOM from CMIP5 to CMIP6 and the configurations of the two experiments are described. Second, the basic performances of the two experiments are validated using the climatological-mean and interannual time scales from observation. We find that the mean states, interannual variabilities, and long-term linear trends can be reproduced well by the two experiments. The differences between the two datasets are also discussed. Finally, the usage of these data is described. These datasets are helpful toward understanding the origin system bias of the fully coupled model.

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Maximum Storm Tide Response to the Intensity of Typhoons and Bathymetric Changes along the East Coast of Taiwan

10.20944/preprints201702.0107.v1 ◽

2017 ◽

Author(s):

Wen-Cheng Liu ◽

Wei-Bo Chen ◽

Lee-Yaw Lin

Keyword(s):

Storm Surge ◽

Return Period ◽

East Coast ◽

Storm Surges ◽

Measured Data ◽

Water Levels ◽

Storm Tide ◽

Astronomical Tide ◽

Extreme Flooding ◽

Bathymetric Changes

A typhoon-induced storm surge is considered one of the most severe coastal disasters in Taiwan. However, the combination of the storm surge and the astronomical tide called the storm tide can actually cause extreme flooding in coastal areas. This study implemented a two-dimensional hydrodynamic model to account for the interaction between tides and storm surges on the coast of Taiwan. The model was validated with observed water levels at Sauo Fish Port, Hualien Port, and Chenggong Fish Port under different historical typhoon events. The model results are in reasonable agreement with the measured data. The validated model was then used to evaluate the effects of the typhoon's intensity, bathymetric change, and the combination of the typhoon’s intensity and bathymetric change on the maximum storm tide and its distribution along the east coast of Taiwan. The results indicated that the maximum storm tide rises to 1.92 m under a typhoon with an intensity of a 100-year return period. The maximum storm tide increased from a baseline of 1.26 m to 2.63 m for a 90% bathymetric rise at Sauo Fish Port under the conditions of Typhoon Jangmi (2008). The combination of the intensity of a typhoon with a 100-year return period and a 90% bathymetric rise will result in a maximum storm tide exceeding 4 m, 2 m, and 3 m at Sauo Fish Port, Hualien Port, and Chenggong Fish Port, respectively. We also found that the distribution of the maximum storm tide on the east coast of Taiwan can expand significantly subject to the bathymetric rise.

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PREDICTION OF MAXIMUM POSSIBLE STORM SURGES IN ISE BAY UNDER A FUTURE CLIMATE

Coastal Engineering Proceedings ◽

10.9753/icce.v33.currents.47 ◽

2012 ◽

Vol 1 (33) ◽

pp. 47

Author(s):

Tomokazu Murakami ◽

Jun Yoshino ◽

Takashi Yasuda

Keyword(s):

Tropical Cyclone ◽

Potential Vorticity ◽

Coupled Model ◽

Storm Surges ◽

Future Climate ◽

Ocean Wave ◽

Storm Tide ◽

Ise Bay ◽

Maximum Value ◽

A1b Scenario

This study aims at investigating space and time–distributions of possible maximum storm surges in Ise Bay caused by potential typhoons based on the SRES A1B scenario. Initial fields of 50 potential typhoons were provided by using potential vorticity bogussing scheme of a tropical cyclone. Then, the distributions over the whole area of Ise Bay under the 50 initial fields were predicted by using an atmosphere–ocean–wave coupled model. The results show that all storm tides in Nagoya Port caused by the 50 potential typhoons exceed 3.5 m which is the largest storm tide ever recorded in Japan and that its maximum value reaches 6.9 m.

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Potential Impacts of Educational Telecommunications Systems

Journal of Educational Technology Systems ◽

10.2190/r94a-7m47-g8xl-mmr8 ◽

1975 ◽

Vol 4 (2) ◽

pp. 77-98 ◽

Cited By ~ 3

Author(s):

Robert P. Morgan

Keyword(s):

Resource Sharing ◽

Large Scale ◽

Social Psychological ◽

Computer Aided Instruction ◽

Education Society ◽

Short And Long Term ◽

Individual Potential ◽

The Individual ◽

Educational Telecommunications

Potential impacts of large-scale educational telecommunications systems are identified and issues to be considered in a more formal technology assessment are discussed. Educational telecommunications systems involving television, computer-aided instruction, and information resource sharing are in various stages of planning and implementation. However, relatively little work has been performed to assess both short- and long-term impacts of such systems on education, society and the individual. Potential impact areas include: impacts on education; economic impacts; political and legal impacts; social, psychological and cultural impacts; physical and environmental impacts.

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