In this study, the tsunami risk on evacuation route calculated by calculating tsunami behaviors of relatively large scale using the tsunami simulation in advance, and evacuation behavior to select evacuation route that does not encounter the tsunami was incorporated into multi agent simulation. As a result, the method of selecting a route that does not encounter the tsunami during the evacuation behavior was established by changing the moving direction to the direction of the shortest distance of another evacuation shelter when there is a possibility of encountering a tsunami during the evacuation behavior calculated from the degree of danger. The area was simulated by this method, and confirmed that the mortality rate was reduced.

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 In this study, the authors developed a tsunami evacuation simulation model considering both local residents and visitors behavior. Using the simulation model, the effectivenesses of enhancing tenacity of a seawall and cooporations among evacuees are investigated in Yuigahama beach, Kamakura, Japan. It was found that enhancing tenacity of a seawall would decrease mortality rate. However, the effects would become minor when its hight is not sufficient. Guiding visitors to an evacuation place would also be helpful to decrease mortality rate but this may cause heavy congestions on the roads. When making a tsunami evacuation plan in a sightseeing location, it is necessary to consider effects of evacuees' congestions.

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 This paper presents a new methodology for tsunami evacuation risk evaluation considering uncertain factors in evacuation analysis based on multi-scenario tsunami evacuation simulation. First, Uncertain factors in tsunami evacuation simulations and its well-defined parameters are organized. Then, the evaluation methodology is applied to an actual urban environment with the defined parameters. Based on the multi-scenario analysis, we found the uncertain factors can have huge effect on simulation results such as evacuation completion ratios. The new methodology can offer reliable evacuation risk evaluation by reflecting the effects of the unsertain factors to evaluation results.

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 We visited houses and stores with Tsuda junior high school students and requested to put a tsunami inundation depth sticker developed by ourselves. We could cooperate with more than 80 percent of 108 people. Effect of the stickers was investigated by the KM-Map method for the guardians of Tsuda junior high school and found that many people did not take the conventional process of “action after understanding” but took the reversal process of “understanding after action”. This feature was analyzed using the questionnaire results, which indicates that those who took the reversal process tend to feel responsible for the students. In other words, regional disaster prevention activity of Tsuda junior high school students seems to enhance disaster prevention measure of the residents in the community.

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 In Japan, tsunami tradition media has been designed to transfer memories and learned lessons of past tsunami disasters. However, the effectiveness of tsunami tradition media to casualty reduction has not quantitatively clarified ever. In this paper, we evaluated them by statistical analysis using the data of the 2011 Great East Japan Earthquake and tsunami, focusing on tsunami monuments and place names stemming from tsunami disasters. Consequently, we drew the following three main conclusions. 1) In the 2011 event, casualties in the areas where tsunami tradition media exists were greater than that where tsunami tradition media doesn't exist. 2) Tsunami tradition media exist in high-risk places which are in danger of being affected by large tsunamis and generating large number of casualties. 3) By statistical analysis, it was revealed that human casualty in the areas where the tsunami monuments exist were reduced in the 2011 disaster. It is possible that the tsunami monuments had any influences to regional residents which contribute to disaster reduction.

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 Disaster Response drills are held actively in various places in Japan. But it is not clarify an effectiveness of participating the drills on actual disaster situation. In this research, we examined the relationship between tsunami evacuation drills and evacuation behavior at the 2016 Fukushima earthquake on 22nd November in Ishinomaki city, Miyagi prefecture based on questionnaire survey and analysis. The results were following. 1) People who participated in the tsunami evacuation drill have evacuated more than 15.2 % those who have not participated. 2) Although there is no difference in evacuation start time between them, people who have participated in the drill evacuated earlier about 3 minutes. 3) 56.7 % of participants could exert a drill experience, and 16.4 % of participants not able to exert the experience.

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 It is necessary that the existence of tsunami monuments is recognized by residents in order to reduce casualties in the tsunami disaster. In this paper, we evaluated the characteristics of awareness for tsunami monuments by questionnaire survey in Rikuzentakata city. Consequently we drew the following four main conclusions: 1) Degree of recognition of the tsunami monuments is 35.0% in Rikuzentakata city, and degrees of recognition were different according to each region. 2) It was found that location and shape are more important than inscription of the tsunami monuments to be highly recognized. 3) Residents who recognize the inscription are less than 40% out of residents who recognize the existence of tsunami monuments. It indicates that it is difficult to transfer the memories and lessons of past tsunami disasters to next generations through the tsunami monuments. 4) It is difficult for children below elementary school age to know that tsunami monuments were made by past tsunami disasters. Additionally, it was clarified that younger residents have the thin relations with tsunami monuments. These knowledges indicate that some support for young generations is essential in order to transfer tsunami traditions through the tsunami monuments.

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 Estimation of human casualty due to tsunami provides us useful information for effective disaster prevention countermeasure. However, there is still no the method that is applicable to various areas because the estimation is strongly influenced by characteristics of the original data. The actual human casualty and building damage data caused by the 2011 Tohoku Tsunami was collected over the wide area and arranged by a fine spatial scale as small as district level. Using such data, we can avoid characteristics of the specific city that strongly influences the estimation results. The ratio of estimated exposure population and actual human casualty is defined as a damage characteristic coefficient which can be explained by the logarithmic normal distribution. The new human casualty estimation model includes the mentioned damage characteristic coefficient. The new model has border application and estimates the damage amount with a range of uncertain. The new method was applied to estimate the human casualty in two different coastal topography areas namely Kamaishi city and Sendai city in case of the 2011 tsunami and verified by comparing the estimated number of casualties with the actual number of casualties.

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 The coastal sandy beach is maintenance-free green infrastructure with self-restoring capability and it is expected to reduce high wave damages with the coastal forest. A number of valuable sand beaches are distributed as a conservation of ecosystems and sightseeing and landscape resources along the Kii Channel. However, depending on the scale of liquefaction caused by the Nankai Trough Earthquake, these functions may not be sufficiently appeared. In this study, we studied Eco-DRR (Ecosystem-based Disaster Risk Reduction) function of sandy beaches in this area through simple liquefaction experiments. The correlation with the ease of liquefaction was high in the order of water content, uniformity coefficient and the coefficient of form unevenness and it was considered that the state of void has impact on the onset of Eco-DRR function.

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 In Hokkaido, Sea of Japan region, there is a plan about aquaculture in fishing harbor. But there is no methods that evaluate aquaculture facility and analysis water quality in fishing harbor. Field observation was conducted to clarify water quality in fishing harbor. We designed the evaluation criteria and biogeochemical cycle simulation to consider appropriate facility for aquaculture. Finally, we propose the evaluation methods and points of discussion to make effective aquaculture in fishing harbor.

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 We developed a new method for valuing tidal flat services, namely, the Coupled Economic and Tidal Flat Health Index: CETHI, which combines the quantification methods of ecosystem status by applying the Ocean Health Index to economic valuation methods. Ten tidal flat services were defined, and the new method was designed to make it possible to the ecosystem status quantification indices being the main variable in economic valuation. The valuation results for 4 tidal flats in Tokyo Bay revealed that cultural services significantly contributed to the total economic value. Furthermore, integrating ecosystem status quantification and economic valuation allowed us to analyze the services' potential, sustainability and the future economic value, which is useful for policy making processes for the tidal flat value.

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 Sandy beach is situated as a shore protection facility from the view of utilization and natural environment. Appropriate maintenance of sandy beach is important to preserve in the long term. To carry out daily checkup to preserve beach appropriately, soundness indicators for beach maintenance are required. However, the soundness indicators have not been established, so far. As a case study of the beach controlled by Niigata Port, soundness indicators are investigated. The soundness indicators depend on individual beaches, in which beach scale against shore protection function and beach deformation characteristics are different beach by beach. The beach scale to fulfill the conservation function is determined by wave runup and wave overtopping, so that the beach scale is set by verifying precision degrees of above two factors. Due to the beach deformation each and every time, preventive indicators for shore maintenance are established in consideration of beach deformation characteristics in long-term as well as in short-term.

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 For the newly formed tidal flats on Benkalis Island in Riau Province, Republic of Indonesia, its formation history and the amount of carbon deposited there were estimated from the field survey. The elevation of the coastal seafloor was initially about -1 m from MSL when tidelands began to be formed. Judging from the satellite image and the result of the field observation, the sandspits which consisted of peat particles deposited first, then the lagoon was formed behind the sandspit. After that, clay particles accumulated in the lagoon. Finally, a tidal flat with mangroves was formed at lagoon. It was found that the secondary sediments derived from the peat that had collapsed on another coast were accumulated in the tidal flat with less decomoposed.

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 Recent erosion on the Cua Dai Coast located on the left bank of the Thu Bon River estuary in Central Vietnam is remarkable. On the other hand, erosion can not be seen on the right bank of the estuary. In order to grasp such asymmetric erosion situation, the characteristics of the topography change were clarified from the Google Earth image and the field survey result. Furthermore, in order to quantify the difference of long-term shoreline change, the coastline position was extracted from Landsat images. The results confirmed the erosion tendency on the left bank and deposition tendency on the right bank. Moreover, by using even-odd analysis, we showed that asymmetric shoreline variation is dominant across estuary opening. Furthermore, the shape of the estuary terrace can be estimated from the position of the breaking wave of the satellite image, and in recent years, the Cua Dai estuary front terrace is biased to the right bank side. It was concluded that the asymmetry of the sand returning from the estuary terrace brings about the asymmetric shoreline variation from now on.

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 In Thailand, although mangrove woods are natural facilities for dissipating waves, since many mangroves were cut down in order to obtain charcoal material, coastal erosion had been caused. From the second half of the 20th century, in addition to felling of mangrove woods for constructing shrimp farms, the large-scale development has caused the same severe coastal erosion as that of Japan.
 At the Chumphon coast in Chumphon Province, dredges and the construction of two huge jetties executed for route maintenance of an estuary port have caused big sedimentation and serious erosion as side effects. Therefore, the future prediction of the shoreline is performed by using the shoreline model which can reproduce this coastal erosion mechanism, and countermeasures for coastal erosion areas are examined from viewpoints of the prevention of coastal erosion and wave overtopping, the conservation of coastal environment, and construction costs: At the erosion area in the north-side coast of jetties, since there are very few buildings, refuge by buying the erosion area is effective; At the erosion area in the south-side coast, since there are a coastal road and many buildings which should be protected, the construction of an artificial reef is effective.

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 It is necessary to set the design tsunami for the maintenance of coastal protection facilities. However, the setting of this tsunami does not have a clear standard. Therefore we calculated cumulative occurrence probability that forcused on occurrence probability of the earthquake by the Headquartere for Earthquake Research Promotion , and we suggested the method with cumulative occurrence probability in this study. Target areas were between Rausu-cho and Fukushima-cho in Hokkaido Pacific coast.

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 The 2016 Fukushima tsunami was caused by a Mw 6.9 earthquake. Though its epicenter was located off Fukushima Prefecture, the maximum amplitude was recorded in Miyagi Prefecture. Two hours after the earthquake, the warning level in Miyagi Prefecture was upgraded from “advisory” to “warning” because the tide gauge in Sendai Port recorded a maximum wave amplitude of 1.4 m corresponding to the second tsunami wave. A numerical analysis and a field survey were conducted to understand the particular characteristics of this tsunami. The tsunami propagation from the epicenter to Sendai Bay was successfully reproduced. Fault orientation, wave reflection and refraction are explaining the unexpectedly high tsunami waves. The observed waveforms at Sendai Port can be reproduced with a purely vertical fault orientation. The field survey determined a maximum runup height of T.P.+4.0 m that occurred in the Miyato area of Higashimatsushima City, Miyagi Prefecture, according to photographs taken immediately after the tsunami. Aerial images from a drone survey showed a tsunami inundation of about 300 m at Gamo near Sendai Port.

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 Although the area has no human damage attacked by Fukushima earthquake tsunami on 22th November, 2016 in Japan, the event has different characteristics from recent tsunami. In this paper, we have conducted questionnaire survey on residents in inundation area at the 2011 Great East Japan Earthquake and tsunami in Ishinomaki City, Miyagi Prefecture to clarify tsunami evacuation behavior. The results are as follows. 1) At the rate of resident evacuated in the survey area was 41.2%. 2) Half of the evacuees by cars caused a delay in traffic jam at the multiple site in the city. 3) Residents who have high risk awareness of tsunami occurrence, experience of high damage in the 2011 disaster and participant of evacuation drill hold by the city evacuated the event more than not.

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 An assessment of tsunami hazard and risk on global scale is important as it can be non-structual measure to increase awareness of coastal residents against tsunami hazards in their locations. However, there are still less number of studies that were focusing on tsunami hazards across the ocean. Therefore, representative cases of tsunamigenic earthquakes were selected based on seismic records over the last 400 years. For each events, distribution of maximum wave amplitudes and arrival times were calculated using tsuanmi numerical analysis in the global scale. In addition, future tsunami hazard assessment was also performed based on the seismic gap. A necessity of assessing both historical and future tsunami hazards in the global scale is then represented in terms of hazard map comparing both scenarios in the global scale.

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 We developed a real-time tsunami detection technique and verified its performance based on a virtual tsunami observation experiment proposed by Fuji et al. (2015). We supposed that a tsunami caused by a Nankai Trough earthquake (Japan cabinet office's fault model case 3) happened at 6:00 on February 1, 2014. We used receiving signals observed on the same day by a HF radar installed on the Mihama coast in Wakayama prefecture and numerically simulated tsunami velocities induced by Nankai Trough earthquake. We found that the tsunami wavefront was detected 13 minutes after tsunami occurance at 31.5 km offshore in the case that the threshold of cross-correlation, which was calculated by observed velocities , was top 1%. The results show that larger threshold enables us to detect the wavefront earlier.

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 For better planning of coastal protection and conservation strategies, development of frequent monitoring of shoareline change is one of important tasks in the field of coastal engineering. Among various satellite data, synthetic aperture radar, SAR, can be considered as one of promissing options for cost-effective monitoring of the shoreline. Because SAR is not affected by cloud coverage and does not require sunlight, it is suitable for frequent observation. This study analyzed a large number of SAR scenes to investigate how various monitoring parameters affect the shoreline detection skills. It was found through the analysis that the most important parameter is the grain size of the bet materials and SAR can be applied for shoreline monitoring under appropriate monitoring conditions.

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 Coastal topography measurements using UAV(Unmanned Aerial Vehicle) was carried out in Fudai beach in Iwate prefecture, Japan. Photographs are taken with a quadcopter and analized using a image analysis software. To increase the prescision of measurement results, GCP(Ground Control Point) measuered with RTK-GNSS system are used. DEM(Digital Elevation Model) of the beach obtained by the analisys include spike-like errors around shoreline according to wave motion. The errors are judged by gradient larger than 30-degree and removed. The results of the analyzation revealed a part of topographic trend in Fudai rivermouth and beach, though consideration to investigate th accuracy is nessesary.

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 In order to estimate the particle size information of surface sediments, experiments to obtain the reflective echo signals from the pseudo sediment using glass beads were conducted. In the experiments, ultrasonic pulse wave was generated by the small transducer and its central frequency was about 550kHz. Characteristics of frequency spectrum of the acquired reflective echo signals was investigated. As a result, the maximum value of the frequency spectrum decreased as the median particle size of the experimental sample became larger. It was found that the correlation between the maximum spectrum and the particle size was very high. In addition, the centeral frequency of the spectrum shifted to the low frequency side as the particle size of the sample became larger in the case of the particle size in the range of 0.150 and 0.355 mm. Consequently, the possibility to estimate the particle size information by ultrasonic pulse wave was demonstrated.

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 A high resolution beach sediment mapping technique was developed on the basis of serial pictures taken from a UAV (Unmanned Aerial Vehicle) mobilized alongshore with a walking speed at an altitude of 10 m above ground. Two dimensional wavelet transform was introduced to determine the size of sediments in the range from 10⁰ cm to 10² cm. The system was applied to the 20 km long Fuji Coast, composed of sand and gravel discharged from the Fuji River. Distributions of sediment size in the foreshore zone were successfully estimated both in the cross-shore and the alongshore directions.

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 The purpose of this study is development of an image analysis method to obtain particle size information by comparison with conventional sieve analysis and detailed particle size analysis by laser diffraction type particle size analyzer (LISST-100). Introduction of the discriminant analysis method demonstrated to determine the binarization threshold automatically for various color characteristics of sand samples and to obtain appropriate analysis results from various sand samples. It was made clear that the minimum number of detected particles was required around 3000 particles by the proposed method to guarantee the results equivalent to the sieve analysis results. Furthermore, the validity of information of particle size distribution obtained by the proposed method was performed by comparison with the results by LISST analysis. By comparison with the results of particle size distribution by LISST, the results by the proposed method indicated the relevant shape of the particle size distribution. These results showed us usefulness of the proposed method as the simple alternative method of sieve analysis.

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 Proving research was conducted offshore Choshi for promoting introduction of offshore wind power generation in Japan. In addition to constructing offshore wind power turbine at about 3.1km off Choshi, we installed meteorological and oceanographic observation equipment. In order to realize the offshore wind farm in Japan, it is important to understand the characteristics by long-term meteorological and oceanographic observation. For this reason, we complied various data obtained in this measurement and understand the wave characteristics off Choshi. Specifically, we clarified the seasonal fluctuation of waves, especially the seasonal fluctuation of low waves which is important for the construction of offshore wind turbine, and also investigated the wave characteristics at high waves.

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 The dependence of the accuracy of ocean waves measured from the Doppler spectrum by high-frequency (HF) radar on the azimuthal difference (Δφ) in the HF radar beams is investigated using numerical simulation. The directional spectrum is most accurately estimated at Δφ = 90°, while its measurement accuracy is least accurate at Δφ = 180°. Nevertheless, it is worth noting that the measurement accuracy is constant in 30° < Δφ < 150°. The dependence of measurement accuracy of the directional spectrum results in lowererd measurement accuracy of wave direction. On the other hand, the measurement accuracy of frequency spectrum weakly depends on Δφ. As a result, the significant wave height and period can be accurately measured regardless of Δφ except in the case of Δφ = 180°

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 Ocean data assimilation (DA) has widely been used for various engineering purposes including monitoring, forecast, and port operations. However, in semi-enclosed estuaries such as the Seto Inland Sea (SIS), Japan, DA has rarely been adapted because satellite data and Argo floats are desperatively unavailable, albeit being essential to successful oceanic predictions. In the present study, we develop a DA system toward rigorous predictions optimal for relatively small coastal and estuarine settings. The system consists of a three-dimensional variational (3DVAR) assimilation scheme being made compatible with ROMS using an in-situ dataset available for the SIS. The DA system significantly improves the reproducibility of water temperature and salinity fields from those without DA. We show an evidence that detailed terrestrial freshwater discharge data is inevitable for more accurate salinity predictions in the estuary.

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 Real-time wave monitoring at marine construction sites is of great importance in construction quality and safety management. A sudden occurrence of a ship wave or long-period wave potentially leads to a severe accident. In the present study, we propose a real-time wave monitoring system in a low-cost and easy way that support marine construction works. The proposed system that consists of a video camera and a laptop PC obtains wave information through image analysis of buoys which are moored around a construction area as off-limits signs. The vertical movement of the buoys according to water surface change is captured by tracking a unique pattern of them with a PIV technique. We confirmed that the system can capture waves in different frequencies with a sufficient accuracy and sampling rate through laboratory experiments and field tests.

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 In this paper, to clarifyiy the releationship between the maximum detection velocity measured by the AT-InSAR and the wave height, the numerical simulation is carried out. The wave height distributions are estimated form theorytical directional wave spectra. The maximum detection velocity in the sight direction were estimated from the wave height distribution form each significant wave period and height. The antennas for the along track interfereometry in Pi-SAR2 couldn't measure the sea surface in the super fine mode with 30 cm resoluteion because these antennas were desined for 300 MHz and 150 MHz bandwidth. To measure the waves in the super fine mode, a new antenna system was developed and a new observation mode (ATI_K mode) was added. To check the capability of the ocean waves observation by the ATI_K mode, the preliminary observation for the ocean waves was performed. The observation area is the sea surface at 10 km off Omaezaki port in JAPAN on the 14th of October 2016. The wind speed was 5m/s during the observation, and the significant wave height and period were 0.9 m and 5.0 s. The significant wave height measured by the ATI_K mode agreed with that measured by the wave gage. The signify wave priod and main wave direction, however, were different from those measured by the wave gage.

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 It's necessary to use a large scale experimental facility and devise the channel in order to generate wave with a sharp peak and a long period. However it's difficult because of restriction on use of experimental equipment. In this study, “slope-type wave making method”, which is not necessary to remodel the facility extensively, is proposed and the characteristics of wave generation and the performance of wave making were investigated using experiments and numerical calculations. As a result, it was demonstrated that the proposed method can produce a sharp wave profile with high reproducibility in experiment. Numerical experiment indicated that the maximum wave height becomes higher by increasing of the volume of water tank. In addition, installation of a control plate on the slope yielded increase of the wave height, and achieved more efficient wave formation by the simple modification. Consequently, it was demonstrated that the proposed method can make wave with a sharp peak by only small modification of a channel.

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