In this study, a typhoon storm surge model, which is forced by a mature-stage typhoon reaching to the maximum potential intensity (MPI), is newly developed in order to predict the long-term variability of the maximum potential storm surge (MPSS) under the future climate projections. We conduct 100-year numerical experiments constrained by the global circulation model UKMO HadCM3 with SRES A2, A1B, and B1. Results show that the linear trend of MPSS increase is higher in the B1 scenario than in the A2 and A1B scenarios, and the yearly fluctuations (i.e. standard deviation) of MPSS during the 21st century are large enough that the largest-scale storm surge disaster is anticipated to occur imminently regardless of how much of the global warming from the present to the late 21st century progresses actually.

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In order to project long-term changes in storm surge characteristics under future climate condition, the present study has developed two types of statistical storm surge models using an artificial neural network (NN). The proposed NN model, which uses only tropical cyclone information, enables to estimate large number event of storm surges using the stochastic tropical cyclone model. The long-term impact assessment of storm surge around Japan can be estimated by the NN and the stochastic tropical cyclone model considering future change of tropical cyclone characteristics.

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The aims of this study are to examine the reproducibility of new Meteorological-Surge-Tide coupled model and to estimate the effect of global warming to storm surge. In order to examine the model, the case of typhoon Roke (2011) is taken to be an example since the sea level elevation in this case is the highest record in Tokyo Bay during recent 10 years. For the case of typhoon Roke, the tendency of time history of water level is well reproduced though the maximum value is underestimated. The future case of typhoon Roke is also calculated. The sea level at Shibaura is increased for around 20cm and it is also increased around 40cm at Funabashi. These results imply that the coupled model has good performance but there are still some differences of sea level at Tokyo Bay due to the effect of complex geography.

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Future projection of ocean wave climate was conducted by a spectral wave model using winds from multi-SST and multi-model ensemble experiments of global climate model (MRI-AGCM3.2H). Future changes of extreme waves were investiged under conditions of tropical cyclone (TC) and Non-TC separately. The spatial distribution of future changes in Non-TC extreme waves in global scale were similar to that of mean waves shown in IPCC-AR5. The 10-yr return wave heights under TC condition in the Western North Pacific showed increase or decrease by 4m for different regions. The spatial distribution can be explained by eastward shift of TC.

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This study projects environmental changes of Seto-Inland Sea in Japan based on the Regional Ocean Modeling System (ROMS) considering CMIP5 ensemble results. The future change of atmospheric temperature, humidity, cloud fraction, wind speed, sea level pressure, short wave radiation and long wave radiation are analyzed by 50 GCM ensemble for RCP4.5 and 8.5 scenarios. The future change of ocean temperature, salinity and currents are projected by the ROMS in present and future climate conditions. The future change of temperature is not uniformly distributed over the Seto-Inland Sea and depends on the local water depth and circulations.

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The future sea level rise (SLR) in the year of 2050 and 2100 are estimated by using ensemble empirical mode decomposition (EEMD) with long-term sea level records in and around the Seto Inland Sea, Japan. Ensemble empirical mode decomposition, an adaptive data analysis method, can separate the sea level records into intrinsic mode functions (IMFs) from high to low frequency and the residue. The residue is considered as the non-linear trend from the sea level records. The SLR trend at Tokuyama in the Seto Inland Sea obtained from EEMD is 3.58 mm/yr over 1993-2010, which is slightly larger than the recent altimetry-based global rate of 3.3 ± 0.4 mm/yr over 1993-2007. Then, the non-linear trend is utilized to project the regional SLR in the Seto Inland Sea. The resulting SLR in 2050 and 2100 estimated are 0.18 m and 0.49 m at Tokuyama, respectively. The SLR is not only due to mass and volume changes of sea water, but also due to other factors such as local subsidence, river discharge and sediments, and vegeta-tion effect. The non-linear trend of SLR, which is the residue from EEMD, can be regarded as a final consequential sea level after considering those factors and their nonlinearity. The EEMD method can be useful tool not only for the SLR projection under climate change, but also for observed data analysis in coastal engineering and hydrology.

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Crown height of a seawall should be designed to suppress overtopping discharge into an allowable level. The allowable level is determined from the viewpoints of the structure type of coastal seawalls and the hinterland use. Since environmental coastal forces, such as sea levels, waves and storm surges, have probabilistic nature, it is usually difficult to design the crown height, especially under the present condition where climate change due to global warming is expected in the future. This study analyzes climate change effects on failure probability of seawalls by using a reliability analysis method of level III and proposes a method to keep the present safety level in the future climate.

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The ocean absorbs about 1/3 of the anthropogenic CO₂ released to the atmosphere. As more CO₂ accumulates in the ocean, the oceanic pH decreases, leading to ocean acidification. In order to better understand the carbon cycle in the ocean and associated long-term pH variation, we estimate CO₂ exchange flux at the sea surface in the Pacific Ocean with the empirical method proposed by Sugimoto et al. (2012) exploiting the publically available oceanic dataset. The oceanic CO₂, the air-sea CO₂ flux, and pH are successfully evaluated for the Pacific Ocean from 1985 through 2008. The pH and CO₂ absorption relation is then argued along with climatological influences during the ENSO events.

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The water current characteristics and energy potential in Tsugaru Strait were investigated through field observation and numerical simulation. Using an ADCP, time series of multilayer velocity were measured during 31 days. As a result, the flow of Tsugaru Strait in the direction of southeast accompanied by periodic variations is constructed by combining the southeastward residual current to the tidal current in the direction of northwest-southeast. The ocean and tidal current in this strait were analyzed using MITgcm. The energy potential distribution estimated from the analysis results indicates that the most appropriate location of power generation is around the side of Shimokita Peninsula coast waters.

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Because of cost reduction for construction and safe utilization of coastal zone and so on, authors have proposed a wave-power generation system which equips Savonius type watermill in the chamber of a vertical-slotted breakwater. In this paper, effect of equipment of watermill in the chamber on reflection function of the breakwater was investigated in detail by conducting systematic laboratory experiments. Based on the experimental results, rate of rotation of watermill was formulated as a function of water particle velocity amplitude through a vertical slit. Further estimation methodology of a primary transformation from wave energy was presented.

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When developing wave overtopping type wave power generation, it becomes an important factor most whether much volume of overtopping is obtained. This research conducts an experiment strict about the volume of overtopping and water supply characteristics which are needed by the design of wave overtopping type wave power generation equipment development, and at least the water of the inside of the tank by the relation of volume of overtopping and volume of overtopping to wave energy and surrounding waters aims it at acquiring knowledge about the water supply characteristics by a difference.

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New method for ocean wave energy utilization is presented instead of conventional wave energy utilization way using OWC (Oscillating Water Columns) with air turbine or another convertor and vibrational power generator using piezoelectric materials. Magnetostrictive vibrational power generator is used as new energy harvesting system. This vibrational power generator device consists of Galfenol combined with iron yokes, coils, and a bias magnet, has advantages from the viewpoint of size, and efficiency, and it is extremely robust and has low electrical impedance comparing with the device using piezoelectric materials. Fundamental characteristics on electric power energy generated from this device are discussed using the experimental data on the electric power energy obtained from regular and irregular wave experiments.

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Development of a device system to extract the ocean wave energy was discussed in this paper. The new facility of wave energy converter called a water-chamber-type seawall has been tested to examine the performance as a wave power extraction device as well as a wave dissipater. The water-chamber-type seawall has a similar structure to the wave energy converter of OWC type (Oscillating Water Column). Wave power is extracted by a water turbine which installed in the chamber. In order to improve the efficiency of wave energy conversion, an axisymmetric guide vane device was applied to accelerate the water turbine of Savonius type. It was observed experimentally that the wave energy conversion efficiency of the proposed seawall is about 18% at maximum. The seawall of this type, however, has another function, such as a wave reflection dissipater. It was also confirmed that the reflection coefficient of the water-chamber-type seawall is about 0.5 in average.

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A way of energy harvesting from ocean power, e.g. tide, current wave, breaking wave and vortex, has been developed using a Flexible Piezoelectric Device (FPED) consisting of a Poly Vinylidene Fluoride, an elastic material such as rubber, silicon and resin, in our previous works. A compressed type of the FPED has been proposed to convert wave power into electric power in this study. The compressed type having a porous resin with a roughness elastic material can generate a high voltage. The electric power is increasing with wave height and the horizontal momentum due to wave breaking phenomena could produce a large amount of electric power.

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The fishery is one of the core industries and many ports are put in place around Awaji Island. If Nankai Trough Great Earthquake happens in the near future, it is expected the coastal regions of Awaji Island will suffer serious tsunami damage. Central Disaster Prevention Council in Japan announced the anticipated damage from Nankai Trough Great Earthquake; however, the verification in detail hasn't been conducted yet. In this paper, we extract the present states and problems by hearing investigations for the managers and examine the characteristics of the anticipated tsunami damage such as submerged depth, temporal limitation of residents and ships by using the announced simulation results.

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In local disaster prevention plan, few local municipalities consider unexpected tsunamis, and most of them make a tsunami inundation hazard map following a scenario which is provided by the central government. Hazard map which shows ranges and uncertainties of the assumption can be more reasonable to understand the tsunami risks in the local scale. Local municipalities also should know the disaster resistance capacity of the region in advance to adjust occurrence of unexpected event. This study assesses the resistance capacity of local communities against tsunami inundation by continuous increase in tsunami intensity. The analysis shows the tsunami magnitude which changes the stage of disaster response referring to loss of shelter capacities in the administrative side and the potentially vulnerable and high risk areas against tsunami inundations in the residence side.

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While tsunami hazard maps show the expected maximum inundation depth, most of them do not show the minimum arrival time that is useful for considering evacuation plans and countermeasures. The objectives of the present study are thus to introduce a concept of an integrated tsunami minimum arrival time that can be used for considering evacuation strategy and countermeasures in order to maximize the least evacuation time among all the expected tsunamis. We applied this concept to the coastal area of Kamakura, Japan, as a case study and created maps for this integrated minimum time using an unstructured grid circulation model, FVCOM. We then considered three types of countermeasures (construction of elevated road, water gate, and elevated river wall) and evaluated them in terms of maximizing the expected least evacuation time and reducing the inundation area. This concept is considered to be useful for planning countermeasures because their effectiveness can be evaluated quantitatively.

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Coastal topographical change around the great east japan earthquake (GEJE), tidal flooding area with inundation height estimated by the observation data, tidal flooding frequency with its height at the widespread coastal area by the numerical modeling of hydrodynamics were examined at the Iwate coast. At the target 4 fishing ports, the waterfront area below altitude 1m was increased by 4.5-12.1 times after the GEJE. Tide level between September 2013 to March 2014 fluctuated in the range of T.P. -1.16m and T.P. +0.89m. Assuming the raising of the land has not been made, the inundation heights were estimated 0.28-0.61m at a maximum. Numerical simulation calculated the maximum inundation height, the averaged flooding rate and the maximum flooding time at each fishing port. In addition, it was suggested that ground elevation and tide level studies in each local unit was important in order to estimate the flood risk.

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On March 11, 2011, the 2011 off the Pacific coast of Tohoku Earthquake occurred. The tsunami generated by the earthquake struck and caused extensive damage to Japan's coastal areas. Because of the unexpected problems, some schools had to evacuate on unplanned route. Furthermore,because of the electric outage due to the earthquake, some schools couldn't get enough information about tsunami. We conducted hearing survey to investigate the evacuation of students of elementary and junior high schools under the unexpected condition. The results of the study are as follows, (1) Seeing tsunami was one of important information and motivation to evacuate to higher place. (2) Some schools changed route and evacuee place to avoid the risk of tsunami or earthquake on March 11. (3) Some schools experienced tsunami, apt to choose new evacuation route and place which they can shelter after evacuation

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Japanese government issued the hazard maps of Tsunami by Great Nankai Trough Earthquake in August of 2012. There are many swimming beaches in Tsunami attacking area. Evacuation plan should be made for beach users because many strangers are there. In this paper, evacuation simulations have been conducted by a multi-agent model to investigate factors for safe evacuation. Walking velocity of users in the sea, on the beach and on the road was used in the simulations. The velocity was figured by using video data of evacuation drill. From the results, it is found that the appropriate settingof guidepanels is an important factor for achievementof safe evacuation.

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In this study, a survey by questionnaire was conducted on the realities of disaster preparedness in 54 municipalities in Chiba Prefecture and six municipalities on the coast of Ibaraki Prefecture. In the study, the knowledge and ability to respond smoothly to a disaster were also examined based on the survey results. There was a significant difference between municipalities in Chiba Prefecture in 2013 in terms of whether they had the standards and process for issuing evacuation orders or not. The ability to respond to a disaster is an important ability for implementing appropriate disaster preparedness for challenges relating to disasters. The ability to respond to a disaster is defined as consisting of specialized knowledge and skills in civil engineering

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Regarding 2011 Tohoku Earthquake and Tsunami, more than 20,000 people were killed or missing. In addition, more than 90% of killed people were due to tsunami. Many people could not or did not evacuate from tsunami despite enough evacuation time and warning information. The awareness of danger in a community increases by not only information given by the governments and the mass media but also behaviors of people in a community. After their awareness reaches their upper limit, they start evacuation. In this study, authors developed the simulation model for the initiation process of community's tsunami evacuation focusing on awareness of danger in a community. Authors verified the model with simple conditions, and validated in the case study of an elderly care facility which was attacked by the 2011 Tohoku tsunami.

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The social welfare facilities suffered serious damage by the Great East Japan Earthquake. This research analyzed the possibility to evacuate the upper floors of its own facility in the elderly group home in the tsunami occurred. There is a risk of tsunami inundation in all group homes of 43 facilities on the coast of Tokushima Prefecture. Those facilities of about 80% are a two-story or one story, and those of about half are located in an area of 2.0-3.0m tsunami normal water level criteria. A result of the comparative analysis the floor height of the facility and the tsunami normal water level, it is possible to evacuate the upper floors in facilities of about 60%, but it is necessary to evacuate the facility outside in facilities of about 40%. Use of the card-type manual that summarizes the action content of the minimum is effective for rapid evacuation. In the group home in Tokushima, evacuation drills were carried out by using it and the residents were able to get more effective evacuation behavior.

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In this research, junior high school students were given lessons on pre-disaster improvement planning for post-disaster recovery a total of eight times (12 hours). (1) Among the learning target items, the highest degree of achievement was for “Learning about the damage in my town.” In the future, it will be necessary to create a wider range of educational materials related to the social circumstances that followed the Great East Japan Earthquake. (2) The majority of students discussed what they learned with family members, friends, and acquaintances. If a common awareness can be created in advance in this manner, it will be very effective in formulating pre-disaster improvement plans while making actual efforts for consensus building. (3) It was possible to demonstrate that this program is an education for sustainable development learning (ESD) method.

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In case of tsunami evacuation, on foot is principle in Japan based on several lessons from the past. However, there is a tremendous need for tsunami evacuation by a car in coastal area where no high ground including high building is found. This paper aims to design a new tsunami evacuation plan with combination of walking and cars in Watari town. The major reasons of car evacuation need is no high safe zone and far out of inundation area in coast. As a result of primary simulation, it is found that 46.0 % people in tsunami inundation area of the 2011 Great East Japan Earthquake disaster cannot escape from tsunami on foot. We propose a flowchart which select tsunami evacuation transportations (walk or car) and suggest directions (horizontal or vertical) for each district, and suggest an evacuation plan combination of walking and cars.

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On March 11, 2011, the 2011 off the Pacific coast of Tohoku Earthquake occurred. After the earthquake, at coast in Iwate prefecture, same as other coastal area, fishermen evacuated to offshore area to protect themselves and their boats. We conducted survey to investigate the evacuation of fisheries in Iwate prefecture and consider whether they can get enough information about tsunami. The results of interview are (1) Evacuation ratio of boats is proportional to the boat size. (2) The depth of the areas boats evacuated to have a variation, and some of them are shallower than 50m. (3) Fishermen on small boats use cell-phone not radio communication system. However at 2011.3.11 cell phone lines were dead or jammed. (4) As boats smaller than about 3tonnage in Fudai and Tanohata, can't get the information of tsunami warning in some area, there is risk to fail to escape from tsunami.

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We performed a stochastic evaluation of tsunami inundation by using results of stochastic tsunami hazard assessment at the Soma port in the Tohoku coastal area. Eleven fault zones along the Japan trench were selected as earthquake faults generating tsunamis. The results show that estimated inundation area of return period about 1200 years had good agreement with that in the 2011 Tohoku earthquake. In addition, we evaluated quantitatively tsunami risk for four types of building; a reinforced concrete, a steel, a brick and a wood at the Soma port by combining the results of inundation assessment and tsunami fragility assessment. The results of quantitative estimating risk would reflect properly vulnerability of the buildings, that the wood building has high risk and the reinforced concrete building has low risk.

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This study presents a method to assess the value of the ecosystem and recreation of beaches on a nationwide scale, and impacts are assessed both without and with the optimal beach nourishment as adaptation to beach erosion due to sea level rise for RCP2.6 (0.39-0.47 m) and RCP8.5 (0.55-0.65 m). The optimal nourishment would cost about 660 billion yen for RCP2.6 and 110 billion yen for RCP8.5. Without nourishment, the Japan's total beach would disappear 84% for RCP2.6 and 94% for RCP8.5 by the end of 21st century. With nourishment, the optimal beach loss rate is estimated 57% for RCP2.6 and 70% for RCP8.5 by the end of 21st century. Considerable limitations remain due to the lack of consideration to ecosystems except beach plants, impacts of grain size on ecosystems, and frequency of beach nourishment.

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The Coast Act was amended, and in addition to "protection", elements of "environment" and "use" were added. The method of evaluating these three elements objectively and determining a priority to perform suitable coastal preservation in a limited source of revenue has not been developed yet. Thus, this research develops a systematized method using the Analytic Hierarchy Process for the priority assessment of coastal preservation. Five criterions, which are "importance of hinterland", "aging of structures", "use", "economy", and "environment", are employed for the assessment. As a result of using the method, it turned out that evaluation of the priority of coastal preservation in Osaka Bay is possible. Furthermore, it is expectable that more accurate assessment can be performed by using more additional evaluation criteria and detailed data.

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Characteristics of isolated islands in Japan are discussed based on multivariate analyses including both principal component analyses and cluster analyses. We focus attention on three parameters of isolated islands: economic power, potential capacity, and inhabitability. Sightseeing is the major economy in Ishigaki Island, while not only sightseeing but also other various economic activities are performed in Amami Oshima for self-sustaining development. The added value of tertiary industry should be converted to income of residents efficiently. The agricultural potential has been utilized to obtain self-organized development in Kita Daito Island. Immediate reconstruction of medical organization is required in almost every isolated island in Japan.

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The 2011 off the pacific coast of Tohoku earthquake caused the extensive damage along the coast of Tohoku area facing the Pacific Ocean with tsunami. Not only Tohoku area facing the Pacific Ocean but also any coastal areas in Japan are under threat of heavy disasters due to earthquakes and tsunamis. It has been clarified that the coastal forestation is effective to reduce the damage due to tsunami by our previous studies on the coast of Sendai plain. In this study, a new index for effectiveness of the forestation against the disaster due to tsunami is deduced from existing data and is extended to other coastal areas in Japan through tsunami height estimated by mathematical simulations by plate tectonics in the central part and southern part of the Pacific side of Japan.

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In 2011, the tsunami in the Tohoku region of Japan was investigated through numerous satellite observations. When a tsunami occurs, many requests are made for an immediate investigation of the damage. Although it has been several years since the 2011 tsunami, it is still necessary to continuously monitor the recovery process. In this study, high resolution satellite images in a time series were used to assess the recovery process in Rikuzentakata City. The recovery process was investigated through classification of the land cover and use of image filtering to analyze surface shape. The amount of bare ground increased in the time series. The tendency for recovery of the regularity of the shape of the land surface was investigated. From these results, the recovery processes were assessed using the characteristics of the land cover and surface shape.

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Beach changes triggered by the 2011 Tsunami were investigated on the basis of aerial photographs, as well as the data set of bottom sounding and the observation results by airbone laser, taking the Yamamoto coast in Sendai Bay as the example. It was found that not only the beach changes occurred owing to the shoreward currents of the tsunami but also sand comprising of the bars was considerd to be transported offshore by the return flow of the tsunami, causing loss of beach sand. The rate of erosion due to offshore sand transport reached 360 m³/m.

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Large-scale sand movement due to the 2011 Tohoku Tsunami was investigated for the Nakoso Coast, Fukushima Prefecture, by using analysis of bathymetry surveys combined with beach deformation simulation. SignificantLarge beach deformation was observed in the north area where many seawalls were destroyed. In contrasts, the sand movement due to tsunami was small in the south area, where the coast is protected by shore-parallel detached breakwaterstructures, although successive storm waves developed subsequent significant erosion by northward longshore transport. The offshore sand loss was foundconsidered to be small since the sand movement due to tsunami was mostly confined in the nearshore area shallower than the closure depth. The total sand loss on the Nakoso Coast was found to be estimated by the co-seismic tectonic subsidence of the order of 40 cm. However, a non-negligible loss of sand was found in the sand transport to the riverland and to the seaA non-Unnegligible loss of sand was found, however, by the sand transport to the land and to the river.

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In this paper, the technique using ship big data as a new technique for grasping a movement of tsunami was proposed. The ship big data is the accumulation data group of data about the cruise situation which is always sending, while a ship cruises, and grasp of the cruise situation of the ship of ocean area is attained in analysing them. As the application, as a result of analysing the ship big data at the time of tsunami on 11^th March 2011, the drift ship group was discovered. Furthermore, as a result of analysing the details of this movement, it was thought that the motion was caused by tsunami. In order to prove this, the statistical method was used and qualitative evaluation was performed. As a result, it was confirmed the drift ship group was moved by tsunami. Thereby, it was clarified that the movement of a drift ship itself is the movement of tsunami itself.

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Super typhoon Haiyan/Yolanda in November 2013 caused coastal flooding and severe damage in coastal zones not only in bays but also along open coastlines. In the Town of Hernani, located on the open Pacific coast of Eastern Samar province in the Philippines, the flooding and resulting washed-away houses were recorded in a widely-viewed video. This paper provides field survey results from Hernani including eyewitness accounts of inundation heights and time series profiles, measured ground levels and estimated sea bottom profiles, and measured dimensions of coastal dikes and of houses shown in the video. Information gathered here suggests that wave groups were the direct cause of coastal flooding in Hernani. Results in this paper will contribute to analysis of large wave disasters and flood prevention in open coastal zones.

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This paper aims to overview the hydrodynamic characteristics of storm surges and waves induced by Typhoon Haiyan around Leyte and Samar, Philippines, especially based on the results of the post disaster joint survey of PICE and JSCE. A number of local residents remained along the coast when inundation started and, based on intensive interviews of those local residents, the survey team obtained information of not only the heights of inundation and run-up, but also other hydrodynamic features such as timings and durations of inundations, flow directions and the level of surface water fluctuations. Comparisons of these findings of the disaster survey and numerical analysis clearly indicated that the wind-induced stormy waves had significant impact on inundations especially along the east coast of Leyte and Eastern Samar.

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The effects of the wind, the storm surge, and the waves of Typhoon 1330 (Haiyan or Yolanda) were surveyed at Tacloban Port and Airport on Leyte Island and at several ports on Panay Island, Philippines. The windows and roofs of the port office buildings were broken owing to intense wind at the majority of the ports. The ground floor was flooded by only the storm surge or by the storm surge and the waves, at Tacloban, Estancia, Caticlan, and Lipata Ports. The wave-induced damage of the wharf was severe at Estancia and Lipata Ports. The containers and the mooring ships were drifted at Tacloban, Estancia, and Culasi Ports by the wind, the storm surge, or the waves. The information obtained through hearing investigation is useful for the calibration of numerical hindcasts.

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The field survey was carried out on damage and corresponding activities on Tacloban Port and Airport and several ports on Panay Islands, Philippines, against Typhoon 1330 (Haiyan) in November 2013. At first, this paper describes the evacuation attitudes of residents against storm surges on Estancia Port and Dumaguit Port through the interview surveys. On one port, port facilities, as public facilities along coast, were used for temporary evacuation. And on the other port, they were used for shelters after disaster. Then, this paper summarizes the advantages and the problems of public facilities along coast for safe evacuation during and after storm surges.

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Super Typhoon Haiyan that struck the Philippines on November 8, 2013 caused over 7,000 casualties by remarkably high wind speed, storm surges and waves. In this paper, characteristics of human loss in the coastal region of Leyte Island, Philippines were investigated based on the relationship between the observed inundation height and depth and the number of deaths and missing people in each barangay. From the analysis, barangays with more than 10 % of the fatality ratio were found along the coastal areas in Tacloban city and Palo and Tanauan municipalities. It was found that the scale of human damage caused by Haiyan is similar to that caused by any other historical tsunami disaster, clearly indicating the massive external force of the storm surge during the Haiyan event and the vulnerability of those coastal areas.

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On November 8, 2013 a powerful tropical cyclone, named as Super Typhoon Haiyan, struck the areas of Southeast Asian countries. The Eastern Visayas in the Philippines was one of the most affected regions due to the high winds and storm surge that inundated and destroyed more than one million houses. In Leyte and Samar islands, approximately 6,268 people were killed. In addition, the Daniel Z. Romualdez (DZR) Airport, located at the Leyte Island in the city of Tacloban, was heavily damaged. In this paper, we briefly describe the damage and inundation mapping effort carried out using satellite imagery and the observations gathered during a field survey conducted in January 2014 with the leadership of the International Research Institute of Disaster Science (IRIDeS) of Tohoku University. The field survey team inspected the affected areas to grasp the inundation extent and comprehend the mechanisms of structural and building damage through inspection and measurement of inundation heights. In addition, survivors were interviewed during the field survey, their experiences of evacuation are summarized here.

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The erosion on a part of the 4.3km long sandy beach on the right side of Cai river mouth in Nha Trang Bay, Vietnam, which is widely considered as among the world's most beautiful bays, has been observed. This study investigates the mechanism of the shoreline variation based on the analysis of the aerial photographs which cover a long time period. The effect of the hotel which playing the function similar to a jetty in the coastal area has been discussed. The analysis also points out that the variation of the shoreline clearly related to the seasonal variation of wave. The erosion occurs from autumn to winter in every years with the dominant of the northeast monsoon. While, in the remaining periods shoreline is advance. Images from real-time monitoring cameras clearly show the variation process of shoreline from season to season,

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Coastal erosion has been a serious problem in the upper Gulf of Thailand. History of its coastline change was analyzed using aerial photos from 1954 to 2010. Abrupt erosion cases were observed around extended channels or after breaching of dikes of shrimp farming ponds while coastlines adjacent to coastal belt of mangroves with 400 m width or more were stable. Adopted countermeasures against the erosion were investigated at two sites where different types of structures, bamboo fences and revetments, were installed, respectively, on the basis of interviews, questionnaire surveys, wave measurements and surveying. A selection policy of measures and recommendations were proposed considering the cost, land use, local opinions and demands and physical properties of structures along with necessity of project evaluation.

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Erosion area, volume and particulate organic carbon emission to the ocean were calculated by the coastal erosion of the Bengkalis Island, Indonesia. In the Bengkalis Island, total of 741 ha peatland has lost from 1998 to 2013. The erosion rate of the coast is almost double in recent 5 years. Annual total of 2.6 Mm³ of the peat and 1.2 Mm³ of the clay have been eroded to the ocean. Annual particulate organic carbon loss from the Bengkalis Island was at the maximum of 0.13 Tg. Also, groundwater emission to the coastal area was enhanced by making constructed water way.

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In cold-region estuaries tsunamis can cause ice cover breakup, ice floe transport and consequent collisions between floes and riverine or coastal structures. The size distributions of ice floes can provide various kinds of information in defining design standards for structures against tsunami run-up. In this study sizes of ice floes after a tsunami event are measured using an image analysis technique and their size-distributions are investigated. A power-law dependence of the cumulative number of broken ice floes whose sizes larger than d was found; N(d) ~ d_-α, which has been frequently observed in the geophysical and engineering contexts. Although there was an increasing deviation from the power law in some regions, the size distribution in four class-1 rivers and a lake was found to obey a power law with similar scaling exponents around 2.8.

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The estimation of a particle size, such as d₅₀, of sediment was attempted by using ultrasonic pulse waves. By investigating the effect of the particle size in reflected waves, it was confirmed that the center frequency, f_c, calculated by the moment of frequency spectrum would be changed depending on the particle size and the strong linearity was indicated between f_c and d₅₀. In case of quasi-suspended situation imitated by a phantom, the relation between f_c and d₅₀ was shown by glass beads though it is insufficient for experimental cases with low concentration. In case of the experiments with sand particles, d₅₀ was overestimated on the whole. This research indicated the possibility of particle size estimation in suspended sediment by ultrasonic pulse waves.

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An object-oriented method to detect building damage is developed using high-resolution synthetic aperture radar(TerraSAR-X) data focusing on the 2011 Tohoku earthquake and tsunami event. To detect changes caused by the tsunami,damage function was developed by correlating mean value of correlation coefficient calculated based on an object-oriented method using pre- and post-event TerraSAR-X data and building damage ratio in each object. The estimated result of damage ratio showed good agreement with ground truth data,showing the pearson's correlation coefficient of 0.96. The method was verified by applying on the other test site,and the results were found consistent with the reported damage features,with correlation coefficient of 0.8.

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A semi-automated tool for detecting tsunami flooded areas is developed using high-resolution Synthetic Aperture Radar data (TerraSAR-X) focusing on the 2011 Tohoku earthquake tsunami event. A number of flood detection techniques proposed in previous studies have not been fully utilized for emergency responses due to their complicated procedures for image processing. Therefore,this study aimed at solving this problem by developing a semi-automated tool to detect flooded areas with a simple interface. The model was applied to Sendai plain and demonstrated a good performance showing producer's accuracy of 94.2 % and user's accuracy of 93.8 %.

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In order to estimate the impulsive force caused by the tsunami debris impact in laboratory experiments, the reaction force acting on the structure which the debris impacts often is measured, and the reaction force is assumed to be equal to the impulsive force. But it is difficult to measure the reaction force is not always equal to the impulsive force because the reaction force is affected by the vibration of the structure induced by the impact. In this paper, we study the measuring method for the impulsive force caused by tsunami debris impact by using numerical simulation. Focusing on the ratio between natural frequency of structure and duration time of impulsive force, we propose the measuring method which can estimate impulsive force with an error within 20 %.

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