THUY LOI UNIVERSITY & UNIVERSITY OF LIEGE MASTER THESIS MODELING STORM SURGE FOR THE NORTH CENTRAL COAST OF VIETNAM Student’s name: Tran Manh Linh Class: NICHE B Major: Coastal Engineering and Management Sustainable Hydraulic Structures Supervisor: A/Prof. Nghiem Tien Lam, Faculty of Marine and Coastal Enginering Thuy Loi University, Ha Noi, Viet Nam Co-supervisor: Prof. Jean-Michel Hiver Université de Liège & Université Libre de Bruxelles Ha Noi- 2016 Declaration Thereby certify the work which is being presented in this thesis entitled, “Modeling storm surge for the North central coast of Vietnam” in partial fulfillment of the requirement for the award of the Master of Coastal Engineering Management and Sustainable Hydraulic Structures is an authentic record of my own work carried out under supervision of Ass. Nghiem Tien Lam and Co-supervisor: Prof, Jean- Michel Hiver.
The matter embodied in this thesis has not been submitted by me for the award of any other degree or diploma, Date: Aug 15,2016 ‘Tran Manh Linh ‘Student: Tran Manh Linh ĩ Class: Niche B Acknowledgements would like to express my sincere gratitude to my advisor Ass. PhD Nghiem Tien Lam and Co-supervisor Prof. Jean-Michel Hiver for their guidance, suggestion and inspiration I would like to express my sincere thanks to University Board of Management, professors and lectures at Department of Marine and Coastal Engineering of Thuy Loi University and professors and lecturers of the Niche programme and Belgian- Vietnamese Master Programme for supporting me throughout my study progress. Finally, I would like to express my special appreciation to my friends and colleagues for their support, encourage and advices.
The deepest thanks are expressed to my family member for their unconditional loves. ‘Student: Tran Manh Linh ñ Class: Niche B CONTENTS. CONTENTS LIST OF FIGURE LIST OF TABLES ABSTRACT 1. Approach and methodology’ 5.
Thesis suture CHAPTER| PHYSICAL SETTINGS 1.1 Geographic conditions 12 Topographic conditions 1.4 Observation stations and hydrologic conditions 1.5 Historical disasters of typhoons and storm surges. 16 Conclusions CHAPTER 2 MODELLING OF NON-TYPHOON CONDITION.1 Introduction model MIKE 21 2.12 Module Mike2I EM 2. Model setup and boundary conditions 22.1 Basic impute data 25 22.2 The digitalized area 26 2⁄3 Model calibration 28 ‘Student: Tran Manh Linh iit Class: Niche B 23.1 Boundary condition and inital condition 2 23.2 The model parameters 31 2.33 Result of model calibration 31 24 Model verification 3 2. ‘The parameter for verification a4 242.
The reslt of verification model 35 2⁄5 Mode! results 36 26 Conclusions 37 CHAPTER3 MODELING OF STORM SURGE. Model setup and boundary conditions a 33 Model calibration 48 33.1 The input data 48 3.32 Result of calibration mỉ 34 Model verification 33 34.1 ‘The result of verification 56 3⁄5 Model results 38 35.1 The result calculation of Mom surge sẽ 3. Sensitivity analysis model s 36 Conclusions 66 Conclusion 6 Recommendation 68 REFERENCES © Student Tran Manh Linh w Chas: NicheB APPENDIXES. n ‘Student: Tran Manh Link v Class: Niche B LIST OF FIGURES Figure 1-1 Administrative map North Central Coast of Vietnam.
10 Figure 2-1 Introduction Mike 21 20 Figure 2-2 Digital elevation model of North central coast of Vietnam in Mike21 Figure malated area Figure 2-4 Location of simulated area, Figure 2-5 Hon Dau, Sam Son location on model Figure 2-6 Diagram ofcalibration process. 29 Figure 2-7 Water level in East condition 3/2007 30 Figure 2-8 Water level in North East condition 3/2007 30 Figure 2-9 Water level in South East condition 3/2007 30 Figure 2-10 Comparison of water level at Hon Dau observation station Figure 2-11 Comparison of water level at Sam Son observation station 32 Figure 2-12 Water level in East condition 11/2007 33 Figure 2-13 Water level in North East condition 11/2007 Figure 2-14 Water level in South East condition 11/2007 34 Figure 2-15 The detail of Manning’s number 3 Figure 2-16 Comparison of water level in Hon Dau station 35 Figure 2-17 Comparison of water level in Sam Son station, 36 Figure 2-18 The detail of Manning's number 37 Figure 3-1 The track of the storm Damrey (2005). 45 Figure 3-2 Flood at coastal zone Nam Dinh in the Damrey typhoon (09/2005), 46 Figure 3-3 The track of the LEKIMA 2007 46 Figure 3-4 Water level in East boundary condition 9/2005 47 ‘Student: Tran Manh Linh vĩ Class: Niche B Figure 3-5 Wate level in North East condition 9/2005 47 Figure 3-6 Water level in South East condition 9/2005 48 Figure 3-7 Pressure in Sep 26 2005 05:00 PM 49 Figure 3-8 Wind speed in Sep 26 2005 05:00 PM s0 Figure 3-9 Wind dteeton in Sep 26 2005 05:00 PM 50 Figure 3-10 Comparison of water level in Hon Dau station in 9/2005 52 Figure 3-11 Comparison of water level in Sam Son station in 9/2005 32 Figure 3-12 Pressure in Oct 03 2007 07:00 AM Figure 3-13 Wind speed in Oct 03 2007 07:00 AM. Figure 3-14 Wind direction in Oct 03 2007 07:00 AM.
Figure 3-15 Water level in East boundary condition 10/2007 Figure 3-16 Water level in North East boundary condition 10/2007 56 Figure 3-17 Water level in South East boundary condition 10/2007 56 Figure 3-18 Comparison of water level in Hon Dau station in 10/2007. 37 Figure 3-19 Comparison of water level in Sam Son station 10/2007 Figure 3-20 The results of calculation storm surge in typhoon Damrey in 2005. 5g Figure 3-21 The track of the typhoon Damrey (2005) 59 Figure 3-22 Storm surge at Hon Dau when change typhoon track 60 Figure 3-23 Storm surge at Sam Son when change typhoon track 60 Figure 3-24 Storm surge at Hon Dau station 62 Figure 3-25 Storm surge at Sam Son station 62 Figure 3-26 Water level at Hon Dau when change wind speed 6 Figure 3-27 Water level at Sam Son when change wind speed 6 Figure 3-28 Models in mike 21 tool box 64 Figure 3-29 Necessary parameters from the formulas which calculate wind field 64 ‘Student: Tran Manh Linh vĩ Class: Niche B Figure 3-30 Water level at Hon Dau Station Figure 3-31 Water level at Sam Son station. 65 Student: Tran Manh Linh vii Class: Niche B LIST OF TABLES ‘Table 1.1 The water level corresponding to the frequency 12 Table L2 The water level corresponding to the cumulative frequeney at Hon Da Table 1.3 Height, length, speed and largest wave period (19561945) 4 ‘able 1.4 Statistics storm in North Central Coast province from 1946 to 2015 17 Table 2.1 Boundary condition of mode.2 The coordinate of observation stations.3 The result of erzor in observation station 33 Table 2.4 The result of error in observation station 36 ‘Table 3.1 The parameter of storm Damrey 2005 48 ‘Table 3.2 The result of errr in observation stations in Storm Damrey 31 Table 33 The parameter of storm LEKIMA (2007).4 The result of error in observation station in Storm, 56 ‘Student: Tran Manh Link L3 Class: Niche B ABSTRACT 1.
Problem statement Vietnam is located in the region where the world’s largest storms in the Pacific North West, occur frequently. This is one of the main types of disasters and dangers in Vietnam, Annually, about 6 to 10 hurricanes or tropical storms hit the country, Storms and tide accompanied by heavy rain that causes coastal flooding. In recent times. along With the effects of climate change, there are many strong storms and super typhoons in the world causing great damages to people and properties, such as Hurricane Katrina in the United States in 2005, Cyclone Nargis in Myanmar in 2008, Typhoon Bopha in the Philippines in 2012,.
In particular, the super typhoon Haiyan in 2013 was the most powerful storm which hit Philippines with strong winds up to more than Beaufort scale 17, caused storm surge up to Tm. It killed! 6000 people and seriously destroyed local infrastructure. About 80-90% of the population lives in the coastal plains in Vietnam which are directly affected by the storms. In the trend of climate change and global warming, the flooding problem is becoming more serious in terms of quantity, frequency and intensity.
‘Moreover, the occurrence of the typhoon: unpredictable Every year, hundreds of people are dead or missing, and thousands of people are affected by storms and floods. Damages to houses, erops and socio-economic are worth upto ten billions, Coastal areas which are densely populated with developed economics, and tourism are very vulnerable and are of very high risk. These areas ate often threatened by coastal erosion, dike breaching, flooding or salinity intrusion caused by storms. In the context of global climate change, many researchers have warned that the storms will occur more often, and more intensely with stronger winds and heavier rains and storm surge is greater than by sea level rise.
Among the 13 largest super typhoons in the World from 1935 to now, 6 new storm occurred since 1998, including 3 hurricanes ‘occurring from 2010 to now in the East Sea including Haiyan (2013), Bopha (2012) and Magi (2010). When the air pressure in the center of storm reduces, large wind often causes of storm surges which can lead to inundating coastal regions. In addition, storm ‘Student: Tran Manh Link T Class: Niche B surges can result in big wave when the storm transfer into the land, destroying sea dikes and coastal works. This then increases the seriousness of the storm.
2, erature review 4) International studies on storm surge Globally, modeling sea level rise by storms is stil being improved in the 21° century “That the storms caused storm surges phenomenon has been studied in areas of the world With different names such as: storms in North America, hurricanes in the Gulf of Mexico and the East Coast ofthe United States; tropical storms in Europe; and typhoons in Asia and Oceania. In the first half of the 20" century, scientists have studied storm surges With existing tools over time: from the simple empirical method based on sparse observation (Conner et al, 1957; Harris, 1959) to the derivatives which are more ‘complicated analysis tools for storms and sea basin, but the value is imited (Proudman, 1954; Doodson, 1956; Heaps, 1965). In the US, Congress has directed the research instituion of the army and the Weather Bureau conducted in-depth research on hurricanes and storm forecasting methods after the immense damage tothe east coast in 1954, This is considered as the beginning of a systematic study of storm surges in North America (Murty, 1984). Before the developed model, the monogram was designed to predict surges whenever a typhoon landed on a beach, Conner and the other researchers (1957) has developed a simple model for calculating approximate peak coastal surges, then draw up the largest water-based monitoring pressure data observed at the center of the storm to determine the best surges envelope, ‘There are many methods and numerical models which have been used to quantify storm surges.
One of the earliest guidelines developed for this purpose is the hurricane scale Saffir / Simpson. Hurricane scale Saffir/ Simpson is oriented like a comprehensive guide for the emergency rescue agencies use in case of a storm. However, this approach, does not reflect the impact of localized factors such as bottom topography changes, shoreline shape, obstructions or other factors to high surges in other locations together when the storm enter the land, Harris (1959) have found a systematic variation of surges with two parameters: the ‘minimum pressure at the center ofthe storm and 91.44 m distance from the center of the Student: Tran Manh Link ?