Dynamical downscaling targeted typhhon Vera under pseudo-global warming (PGW) that was based on JRA-55 and SST ensemble experiments using MRI-AGCM3.2S was carried out. Future change parameter sensitivity analysis of SST, air temperature and air pressure gave results that PGW experiment by only SST made typhoon to strengthen excesively (decrease 40 hPa in minimum pressure) and taking air temperature and pressure in account made typhoon minimum pressure to dexrease 10 hPa. Every PGW experiment made typhoon route to shift to west. Storm surge simulation using empirical typhoon model estimated surge level raise of 26 cm on ensemble average.

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 Ocean surface waves take important roles at an interface between atmosphere and ocean. The wave-dependent surface roughness was implemented into the Atmospheric Global Climate Model using the spectral wave model, and climate simulations were conducted. Wave steepness- and wave age-dependent roughness were considered. The spatial distributions of roughness climatology correspond to the dominance of swells for the climate simulation with wave steepness-dependent roughness and the stationarity of wind direction for that with wave age-dependent one, respectively. The differences of roughness cause the differences in surface wind climatology by 1m/s compared with uncoupled simulations, large differences especially at the lower-latitude. Furthermore, we indicate that the influences can extend to upper-atmosphere such as the climatology of tropical cyclone track. Implementing ocean waves into a climate model can have a wide impacts on the climate simulations.

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 We studied medium and long term change charasteristics of wave around Hokkaido coast by weather change. Energy flux and maximum value of the significant wave height were longitudinally increased by global warming and etc.. Medium term change of mean wave directions are correlated with relative sunspot number and PDO index. Medium term change of wave energy fluxs are correlated with AO index. The change of wave direction can be estimated by the change of relative sunspot number with about ten years period.

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 This study aims at establishing a comprehensive scheme to evaluate the risks of future coastal flooding. To confirm the effectiveness of the proposed method, this study applies the model to practical risk analysis in the North Somerset coast in the UK under 10 different cases. Furthermore, this study develops an optimization procedure using the results of analyzing the implementation of different countermeasures. The results of the coastal flooding analysis clarified that sea level rise is the highest impact factor in North Somerset. The incremental countermeasures could be effective for the middle maintenance strategy although the optimum adaptation plans depend on climate change scenarios and maintenance strategies. Application of this proposed procedure to actual coast enhances future coastal risk management.

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 This paper simulates drainage of infuluent water caused by tsunami of the Nankai earthquakes. The target area is Okinosu, Tokushima. To simulate inlands water flow, we attempted 3 layers model, which is composed of ground, channel, and sewer. These 3 layers exchange water each other. Finally, water is drain to foreland by drainage pumps. In a simulation using the Ansei Nankai earthquake source model as input, if all drainage pumps works, the drainage finish about 16 hours after the earthquake. But, some water is not drained because of sunken place. If pumps that are top 3 of the drainage capacity don't work, the drainage finish about 72 hours after the earthquake. In this case, water which is not drained is increased. In a simulation using case 3 of Cabinet Office earthquake source models as input, because of big displacement in this area, certain boundary area becomes lower than sea level. So, water comes inland always.

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 We demonstrated a new wave energy converter successfully at Ooarai port in Ibaragi. This is a kind of point absorber using a box shaped float heaving along a pile fixed on the sea bottom. The active absorption control, developed for wavemakers more than 30 years ago, was modified to realize resonant control. Conversion effeciency of the devie is more than 70 % at incident waves of 10s in period and 0.5m in height.

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 Authors have been developed a wave generation system using the vertically slotted breakwater and savonius-type water mills for several years. It has been already found from a series of a hydraulic experiment that the wave generation system have a superior wave attenuation function for wide range wave frequency rather than the present breakwater and that rotational velocity of a water mill can be estimated by using water velocity through a slit. However, the knowledge for the irregular wave has never been obtained at all. Hence, in order to obtain the knowledge for the irregular wave, hydraulic experiment was carried. It is found out that attenuation fuction will be superior by introducing water mills into the chamber. The estimation formula of the power of a water mill from waves is also introduced.

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 In this study, laboratory experiment carried out to measure electric power generated by new vibrational power generator using piezoelectric materials. U-type shaping device is adopted in this new power generator, and two types of wave receiving, plate-type and buoy-type, in front of coastal and harbor structures are tested.
 As a result, it is possible to continue 10 times vibrational time compared to the time by previous power generator that adopted cantilever-type shaping devise. And it is also possible to generate 20 times electric power compared to the power by previous cantilever-type shaping devise.

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 We develop a weather routing (WR) system for vessel navigation based on the A-star algorithm, a descendant of the commonly used Dijkstra algorithm in graph theory. A cost function is optimally modified to account for oceanic conditions (viz., surface current velocity) around the vessel of interest. Three options are thus considered to search for the optimal paths with the shortest travel time, the minimal fuel consumption, and the shortest travel distance. An avoidance algorithm from unsafe conditions is further introduced to exempt any arbitrary area from the navigation. Furthermore, a compact ocean circulation model based on ROMS executable on typical laptop PCs is configured for a vessel-borne weather routing system and is successfully applied to evaluate the optimal vessel paths in the Seto Inland Sea where high-frequency tidal currents modified by complex topography are essential to alter the vessel's speed. The WR system with the avonidance algorithm is then exploited to two evacuation problems from a migrating typhoon around the vessel paths and radionuclides at ocean surface after the Fukushima nuclear accident.

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 In this study, the analysis of tsunami evacuation based on cellular automata method is proposed. Because the problems of tsunami evacuation simulation in order to plan for effective breakwaters and seawalls to the reduction of loss of human lives by the tsunami was considered. Tsunami evacuation using the shortest route to the end point and inundation that changes from moment to moment are uniformly analyzed based on cellular automata method. Accordingly, the point where the damage to each evacuation start time occurs are shown if the fastest escape route is used. In this paper, it is considering changing the specifications of the breakwaters and seawalls of Shimizu. Then, the possibility of loss of human lives is increased is revealed by the multiple placement of tsunami measures. Also in this paper, the existing development plan on tsunami measures in Shimizu Port is referred. From the study results, measures should be given priority in development is estimated that raising the breakwater.

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 The purpose of this study is to verify the effect of the seawall height on successful evacuation rates. The relation between the height of seawalls and the mortality was analyzed using the data of past questionnaires. Furthermore, numerical tsunami and evacuation simulations were performed for two towns to verify the effect of different seawall heights on morality. Under Tohoku tsunami conditions, the results indicate that early evacuation is more effective in decreasing mortality rates than constructing higher seawalls. The numerical results show that the inundation area decreases by 5% and the mortality decreases by 10 to 20% when the seawall height increased. On the other hand, the mortality rate was reduced to zero when the start time to evacuation is within 10 min.

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 This study attempts to investigate effect of a tsunami evacuation tower by using evacuation simulator is coupled with tsunami simulator. This simulator calculates the behavior of evacuation and tsunami at the same time. Thus, the difference of the human suffering and the impact on the evacuation behavior were validated. As a result, in this study's conditions, when the evacuation tower was established at the location near coastal area, it was confirmed possibility to encounter tsunami rises depending on the evacuation start time. On the other hand, when evacuation starts earlier than tsunami arrival time, it was confirmed that it is possible to significantly reduce the death rate. Finally, the effect of new tsunami evacuation tower was validated. As a result, it was confirmed that the death rate is decreased by shortening the average evacuation distance.

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 The relocation to the higher ground area or the effective evacuation plan are discussed as the alternative countermeasure of the coastal protection device. In this study, the selection method of the soft-type countermeasures combined with the coastal protection device is proposed, based on the tsunami risk evaluation by using the evacuation model which can be taken into account of the complexity of the evacuation path.
 The human damage in the areas divided with inundated depth is analyzed under the several condition of the seawall heights. There are some characteristic areas. There are the habitants can prevent from the huge human damage by comparatively small seawalls. On the other hand, the peple in the other area is difficult to prevent the damage even if the large scale of seawalls installed and must select the relocation. The countermeasure on the improvement of the evacuation is picked up by the analysis of the length including the complex evacuation path with GIS data.

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 To prepare a more practical evacuation plan to combat unprecedented multiple disasters, the tsunami numerical model was developed and a GIS analysis of tsunami evacuation behaviour after the Great East Japan Earthquake was conducted at the Otsuchi coastal region. The arrival time and the inundation process of tsunami between Ando and Kirikiri district, a distance of merely 2 km, were significantly different and showed unique regional characteristics. The GIS analysis clarified the lack of imagination of tsunami destructive power, the cognitive status of designated location of the shelter, the evacuation behaviour during tsunami attack, and proposed the issue of shelter placement based on these. Considering the past disaster and the potential risk involved, a new evacuation support map for recognising various natural disasters was developed and the nearest site for shelter was located and checked for its accessibility.

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 Repeating a practical evacuation drills are important, and such a drill is often hold recently. But the effectiveness of repeating evacuation drills is not evaluated objectively. The purpose of this study is to demonstrate the effectiveness of repeating evacuation drills which were hold in Watari town every year from 2013. The three focuses of this demonstaration are residents' evacuation time, efficiency of checking students' safety and reflection after the drill. The results were the followings: 1) The rate of residents which can be evacuated from inundated area was increasing. 2) The efficiency of checking elementary and JHS students' safety was increasing. 3) The new problems for drill were found and the old ones were improved or decreased.

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 Based on lesson learned from the 2011 Great East Japan tsunami, tsunami height is the most influential factor on fatality of people living in coastal area. This paper proposes effect of breakwaters on fatality ratio of people and investigate a reduction of fatality ratio due to the existence of breakwaters. For preliminary study, 24 fishery ports equipped with breakwaters were selected to study how breakwaters affect to loss of fatality ratio along Sanriku ria-coast from Taro to Ishinomaki. The port area behind breakwaters was considered to calculate fatality ratio from number of fatality divided by total number of people and then fatality ratio was linearly correlated with observed tsunami height. In order to estimate fatality ratio in case of ports without breakwaters, simulated tsunami height was calculated by TUNAMI modeling with nesting grids of 1350 m, 450 m, 150 m, and 50 m. For the overall image, breakwaters could reduce fatality ratio of people in the port area with a percentage of reduction approximately 30%. Considering the effect of breakwaters at each port, it was found that fatality ratio of ports equipped with breakwaters is less than those in case of ports without breakwaters for most of ports. In addition to these 24 ports, 18 additional ports equipped with breakwaters were conducted to additional study and compared with 24 ports having no breakwaters. For the overall image, the percentage of reduction became 1%, which is much lower than the reduction in the preliminary study. Focusing on each port, two third of them still provided the reduction of fatality ratio.

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 Quick evacuation action is a key to survive against Tsunami disaster. For a quick evacuation, it will be indispensable to investigate an evacuation planning with a highly reliable data, that will be provided from simulations by considering as many disaster conditions as possible. Authors have performed several evacuation simulations by the DEM-based crowd behavior simulator so far but a multilevel structure of buildings was not considered there, even though it is expected that evacuations from buildings with multilevel structure will have a significant effect on a completion time for an evacuation.
 In this study, evacuation simulations with consideration of a multilevel structure of buildings have been carried out with applying photogrammetry data, and the influence of amount of information as to height of buildings on evacuation processes has been examined. As a result, although slight difference is found in the completion time for evacuations, considerable differences are shown in the evacuation process according to the difference of the amount of information of the height of buildings.

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 The regional death ratio varied depending on whether a sea was visible or invisible during the Great East Japan Earthauqke and Tsunami. In the present paper, we developed the tsunami evacuee generation model with a regional coefficient R. The model was applied to the actual district, and it was clarified that a sea-side area should have 3 to 11 times larger R than a land-side area to reproduce the regional difference in a death ratio. The proposed coefficient is available to analyze numerically a regional difference for start of tsunami evacuation.

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 Shikoku Island in Japan faces a severe risk of Nankai earthquake which will be occurred in near future. In this island, there are many shrines around the coastal area. In this study, in order to examine the conversion of the shrines into evacuation sites, using the spatial information of shrines and the results of numerical simulation on tsunami damage, tsunami suffered risk of each shrine was clarified. Moreover, the difference of characteristics for damage risks of each enshrined god was examined.

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 In the Tohoku Pacific Ocean Earthquake, some tsunami evacuation buildings have been exposed to the risk of fires. It highlights a requirement of the tsunami evacuation buildings for the tsunami fires. Most of existing risk assessment methods of tsunami fire predicts macroscopically the number of fires and its scales within a large area. In order to estimate risk of tsunami fire for a certain building, it is essential to consider the circumstance of the local terrain and surrounding buildings. In this study, the relationships between tsunami fire risk and debris distribution was investigated analyzing aerial photos and LiDAR data after the tsunami. Furthermore, the statistical model for estimating the risk of localized fire at 100m mesh was proposed.

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 In this paper, we considered the relationship between tsunami monuments and historical tsunami inundation areas, focusing on 176 tsunami monuments in the coastal area of Iwate prefecture. Furthermore, we also discussed the effectiveness of tsunami monuments in reducing human casualty in case of the 2011 Great East Japan earthquake and tsunami. Consequently, we drew the following four main conclsions. 1) About 75% of the tsunami monuments in the coastal area of Iwate prefecture were located outside of inundation area of the 2011 tsunami. The locations of these tsunami monuments can be target points for tsunami evacuation in the case of large tsunamis such as the 2011 event. 2) If the inundation area of the 1896 Meiji Sanriku tsunami was considered, some of the tsunami monuments based on the 1933 Showa Sanriku tsunami, which were located inside the inundation area of the 1896 tsunami and the 2011 tsunami, might not be damaged by the 2011 tsunami. 3) Based on the analysis of relationship between maximum height of tsunami and human casualty in each local district, human casualty against the maximum height where the tsunami monuments were located outside of the inundation area is smaller than that where the tsunami monuments were located inside the inundation area. 4) Since some of tsunami monuments with the function of education are located inside of historical tsunami inundation areas, this lead to increasing human casualty.

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 Analysis of human casualty have been studied with data in city or town scale. However, analysis in these scales cannot capture the casualty characteristics that vary even by small administrative areas. This leads the difficulty of human casualty estimation for future tsunami disasters. In this paper, we conducted statistical analysis of human casualty in the 2011 Tohoku tsunami especially focusing on Ishinomaki City, where had the largest human casualty in this tsunami event, using the casualty data in fine scale as small as district level. The results show high correlation between tsunami inundation depth and fatality ratio and also building damage ratio in fine scale. Factors that might lead to large human casualty were considered based on the result. Statistical model explaining fatality ratio using tsunami inundation depth and building damage ratio were developed. These models show possibility of fatality estimation in future tsunamis under certain conditions.

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 We evaluated the application of time-series InSAR analysis for the deformation on a reclaimed land of airport and a concrete structures in a harbor area by use of ALOS data. ALOS has capability of 3 to 4 times observation in a year throughout Japan, 10m resolution, measurement in 50 to 70 km square area for less than a minute. The time-series InSAR analysis of ALOS repeatedly measures targets on the ground as ‘surface’ not as ‘point’ like GPS without setting receivers. Furthermore, it enables to acquire information about past deformation even when we have not recorded it, with the analysis of the observed ALOS data. These advantages are useful for the monitoring use if its accuracy has been demonstrated. In this paper, measurement data in Kansai international airport are used for accuracy assessment and a case on an irrigation channel in Onahama harbor is analyzed.

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 Assessment of aggregate loss becomes important in the Enterprize Risk Management. Municipality usually assesses storm surge damage caused by an expected maximum typhoon, and its procedure does not considers simultaneous damage occurrence in multiple areas. This study develops integrated disaster assessment method of storm surge damage considering simultaneous occurrence in the three major bays: Tokyo, Ise, and Osaka. Stochastic typhoon model enables to estimate probability of typhoon passing through the multiple areas. Nonlinear shallow water model estimates inundation area caused by storm surge and loss on assets in hinterland. Loss function which represents loss and return period of typhoons, and an event curve which represents loss and annual exceedance probability are used for risk assessment. The proposed method shows that aggregate risk is different depend on return period. For the worst class typhoons, the aggregate risk in Ise and Osaka bays becomes larger than the single risk in each bays.

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 A numerical simulation model, which can calculate spread of inundation area on the ground and in the space of subway track by a severe storm surge and river flooding simultaneously, is developed and described in detail. Based on the calculation results, quantitative analysis of characteristics of simultaneous occurrence of inundation due to storm surge and river flooding are presented. Moreover, evacuation activities appropriate to occation of water disaster are also reffered.

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 The accident that three children and two adult males who tried to rescue the children died occurred at Jogehama beach in 2014. The beach was known in the around area for the small cusp topography and steep slope. Therefore, the beach was the swimming prohibited area, and they played on the beach when the accident occurred. However, the big wave suddenly run up to the beach, and the children were swept out to sea. Following the accident, we investigated the causes why this accident occurred. Firstly, we comprehended the wave condition when the accident occurred. Secondary, we conducted field survey to obtain the topography of the field. The geographic data for the numerical simulation was made from the aerial photograph that was taken by Drone. Finally, we comprehended the wave dynamics on the beach by the horizontal two dimensional numerical model and the vertical two dimensional numerical model.
 This study conducted the numerical simulation, and the simulation reproduce that the run up wave on the beach converge into the depressions of the cusps, and the backwash current flows in the pectinate where the lowest place in the cusp. Furthermore, the run up velocity on the beach became about 6m/s, and the water level nearby the shoreline became about 1m. According to these results, the people on the beach need to take care not to be sudden attack of the big wave.

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 An asymmetric distribution of sand supplied from the river at a river mouth delta has been discussed. The current erosion situation of Cua Dai Beach in central Vietnam was first introduced using Google Earth images. The evolution of the Thu Bon River delta coastlines were also analyzed using typical Landsat images from 1975 to 2014. It was observed that there were three periods in the formation process of Thu Bon River delta during the last 40 years with the symmetrical and asymmetrical configurations of the two coastlines. This evolution and its relation to the sediment supplied from Thu Bon River were then quantitatively investigated using analytical solution of one-line model.

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 Phenomenon of accretion and erosion at the Darang River mouth has been observed to be severe for a long term. Based on Landsat images, the long-term evolution of this area from 1988 until now has been raised to discuss. Shoreline variation around the river mouth has happened in an unpredictable way; indeed, the areas adjacent to the river opening have much changeable while the areas far from the river mouth have been seen to have minor change. This study applies even-odd function method to analyze the variation of shoreline at the Darang River mouth. The formation of both sides of the river mouth varied consecutively in the period from 1988-2015.

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 This study focuses on tidal flow characteristics in the confluence of Yangon and Bago River, Myammar. Field surveys were conducted in the end of the rainy season and the dry season to obtain water surface evolution and flow velocities around the confluence. A numerical model was constructed on the basis of the field data to investigate detailed flow structures due to river and tidal flows. The results suggest that the tidal flows are dominant over river flows during the survey periods, and the asymmetric tide produces high ebb velocity especially in the Bago River, leading to net sediment transport to the confluence.

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 The Arabian Gulf (also known as Persian Gulf) region is one of the most important oil producers to fuel the world and most of the population is located along the coasts. The present study aimed, for the first time, to carry out some preliminary assessment of the tsunami hazards in the Arabian Gulf region using numerical model. This study tsunamis generated by submarine earthquakes with the earthquake magnitude (M_w) of 8.3-9.0 along the Makran Subduction Zone (MSZ) and surface landslides with the volume of 0.5-1.0 km3 along Iranian coast inside the Arabian Gulf. TUNAMI model was applied in this study to predict the tsunami propagation. The model adopts the staggered leap-frog scheme to solve shallow water equations describing nonlinear long-wave theory. GEBCO 30 arc-second grid data was used as bathymetry and topography data for tsunami numerical simulation. This size of the computational grid was ascertained by many previous studies for its suitability in evaluating tsunami hazards in this region. For surface landslides, tsunami generation was simulated using a two-layer numerical model developed by solving nonlinear long-wave equations within two interfacing layers with appropriate kinematic and dynamic boundary conditions at seabed, interface, and water surface. In case of the earthquakes along MSZ, M_w 8.3 has low impact to locations inside the Arabian Gulf. M_w 8.6 has considerable impact mainly at the Gulf entrance meanwhile M_w 9.0 has high impact at the Gulf entrance and negligible impact for the whole Gulf region. In case of the surface landslides inside the Arabian Gulf, the impact is rather local but major near the sources. Detailed estimation of landslide volume, tsunami simulation using very fine topography and bathymetry data and coupling tide and tsunami wave modeling will be considered for the future works.

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 Numerical simulations for implementation of efficient countermeasure against lagoonal pollution in Funafuti Atoll of Tuvalu were conducted in this study. In the simulation the spatial differences of pollutant outflow were estimated by using the houses distribution. Fongafale Island was divided into the three areas where countermeasure was implemented, and the six countermeasure scenarios were considered in total. Pollutant volume was estimated in six small regions that covered whole of Funafuti Atoll. Effective countermeasure case was different in the small regions. Thus, appropriate selection of the target region of pollution reduction enables to decreasing number of houses which implement the countermeasure. Countermeasure efficiency parameter indicated that the countermeasure in the middle of Fongafale Island where has high density of houses had high efficiency for reducing the pollution.

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 In order to establish method to evaluate erosion resistance and the critical resistance to erosion of vegetation such as trees on coastal dunes, hydraulic experiments were carried out. 7 samples were collected from 3 regions. Depth of erosion was measured at every passing water, which flow velocity was about 7 m/s at maximum. The velocity of erosion was unspread at surface layer as time passed . But the depth of erosion exceeded a certain depth, a sudden increase in the velocity of erosion was shown. The depth was defined as critical resistance to erosion. The critical resistance to erosion varied in every sample. The range of the critical resistance to erosion was about 10cm to 20cm. The range generally corresponded with the depth which the amount of roots decrease drastically. These result suggested the relation between the critical resistance to erosion and the vertical profile of the quantity of roots. Additionally, the evaluate fomula for resistance to erosion was studied using results of hydraulic experiment.

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 To assess paleo-tsunami history, we studied coastal lowland on Oga city and Happo town, middle-northern part of Akita Prefecture, at the eastern margin of Japan Sea. From boring cores in these study area, we found coarse grained sediments in organic mud and peat that were deposited in marsh. These coarse grained sediments has some sedimentological characteristics, such as, erosional lower contact, rip-up crusts, parallel and cross stratifications, upward fining, and plant fragment laminae. These sedimentary features indicate formed by strong currents. Therefore, we interpreted these sediments as an event deposits. We recognized these event deposits as a tsunami deposits based on their sedimentary features and geographic setting around these boring sites. We used radiocarbon ages from plant materials to determine the ages of deposition of these tsunami deposits. Depositional ages of these tsunami deposits were interpreted 13^th–15^th -century and 16^th–17^th -century by calibrated ages.

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 The Okoshiki Coast in Uto City, Kumamoto Prefecture, Japan, is a beautiful sandy tidalflat with rhythmical variation of multi-bar-trough structure. To investigate the sediment stratigraphy, multi-channel analysis of surface waves (MASW) was applied to this sandflat; however, the conventional method using geophones was only applicable to exposed regions in supralittoral and mediolittoral zones. In this study, MASW array was extended from mediolittoral to infralittoral zones by using hydrophones instead of geophones. Sediment stratigraphy was successfully evaluated by using geophones in supralittoral and mediolittoral zones during exposed periods and using hydrophones in mediolittoral and infralittoral zones during submerged periods. In the MASW survey using hydrophones conducted on a boat, it must be noted that the shear wave velocity structure at shallower depth is influenced by the offset distance between the shot point and the nearest hydrophone.

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 The geological features in singing sandy beaches can be devied into three types. These are the dynamic equilibrium becch, indicating the domination of pocket beaches it the area. The prominent sand color in singing sandy beaches was brawn. The major chemical elements are as follows; Si, Al, Ca, Fe, Na, K and Mg. There is little difference between singing sandy beaches and general sandy beaches on chemical elements. However, Ohyama beach in Yamaguchi Prefecuter is rich in Ca. The 1^st peack frequency of singing sand sound is related to sand grain size, 2^nd the sorting coefficient.

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 A Bayesian inversion method for estimating the directional spectrum in deep water (BIM_deep) has been modified to accurately estimate the directional spectrum of ocean waves in shallow water from the Doppler spectrum measured by high frequency (HF) radar. The applicability of the modified Bayesian inversion method (BIM_shallow) and BIM_deep in shallow water has been verified by numerical experiments. We found that BIM_shallow can accurately estimate the directional spectrum even if the Doppler spectrum depends on water depth due to the linear dispersion relation in shallow water. In contrast, BIM_deep cannot accurately estimate the directional spectrum in the range of relative depth less than or equal to 1 (h/λ ≤ 1). Consequently, BIM_deep is applicable when h/λ > 1.

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 VHF ocean radar observations off the east Enshu coast and tsunami simulations against great earthquakes along the Nankai Trough were conducted, and the pseudo composite current data of tsunami propagation were created to superimpose the tsunami simulation data on the observational current data by ocean radars. It is found that the tsunami comes mainly from southeast direction to the Enshu coast and almost arrives in 20 minutes after the earthquakes. The maximum tsunami height based on radial current velocity by ocean radar observation and water depth is a useful index as tsunami detection, which well represents the spatial and temporal variation of tsunami event. It is also indicated that the window time from the tsunami detection to tsunami attack to the Enshu coast with the VHF ocean radar observation is about 5 to 15 minutes.

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 A tsunami generated by “The 2011 off the Pacific coast of Tohoku Earthquake” was observed by two oceanographic radars in Ise Bay. This tsunami generated the natural oscillation with period bands of 120-140, 60-90 and 30-40 min in the Bay. To clarify these oscillation modes, we used an EOF analysis on the total velocity data and numerical calculation proposed by Loomis. From the results, we showed that the oscillation modes of 120-140 and 60-90 min period bands were comparatively wide-area oscillation, whereas the oscillation mode of 30-40 min period bands was extremely local oscillation.

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 We evaluated the accuracy ratio between tidal levels and currents by MILT Ocean Radar in the ISE bay for data assimilations. We calculated variance-covariance from 13 tidal constituents of M2, S2, K1 and O1 for tidal levels and velocities in sequential every 151 days for about 6 years from 22nd Apr. 2008 to 8th Oct. 2013. Since the tidal constituents of M2, K1 and O1 for tidal levels show periodicities by 18.6-year period lunar nodal tidal cycle, a f-value for amplitude in 18.6-year period, correction is required in order to evaluate the variance. The variance-covariance of currents represents similar to the geometric dilution of precision calculated⁴⁾ by the angle of beams and suggest the positions at which the radial velocities could not be measured. The ratio of variance-covariance of M2 and O1 constituents between tidal levels and currents is potentially applied to the accuracy ratio between them for data assimilations, because M2 and O1 constituents do not represent seasonal and annual variations unlike O1 and K1.

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 Synthetic Aperture Radar (SAR) is a powerful tool in retrieving shoreline positions and surface wave patterns in the nearshore, since it can gather scenes in any weather condition. The interpretation of scenes is sometimes not straightforward due to the various parameters set in the active observation of SAR. In this study, several scenes which captured Kashimanada Coast, Japan were analyzed to infer the usability of SAR data to extract shoreline positions and wave number variations in the nearshore, and also the influence of various parameters in the observation is discussed. Shoreline positions along the 15 km long sandy beach were digitized manually from the scene, and compared with aerial laser scanning survey data. The mean accuracy of shoreline position detection was in order of 10 m, which is equivalent to the resolution of SAR observation. Local accuracy decreased at regions where local foreshore slopes were mild, which was probably affected by the water content in the surface layer of sandy beach. Wave number variations from offshore to onshore were analyzed with two dimensional Fast Fourier Transform. Refraction of waves was confirmed: increase of wave number and deflection of wave angle. Off-nadir angle in SAR observation is an important parameter in coastal observation. If this angle is set to an optimized value for land observation, backscatter from water bodies is small. On the other hand, if this is angle is set smaller, backscatter from water bodies increases and wave pattern and shoreline position are captured more clearly.

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 In this paper, to estimate the distribution of the wave height by the along-track interferometry SAR (AT-InSAR) precisely, the relationship between the wave height and the sea surface velocity measured by the AT-InSAR was clarified and a method to estimate the wave height from the measured sea surface velocity was developed. In addition, to check the capability of the ocean waves observation by the AT-InSAR, the preliminary observation for the ocean waves was performed. The observation area is the sea surface at 10 km off the coast of Kushiro, south-east to Hokkaido, JAPAN on the 4th of March 2015. The wind speed was 8～10m/s during the observation, and the significant wave height and period were 1.4m and 6.0s. The observation was performed in 2 directions and the accuracy of the estimation results was checked. The significant wave height measured by the AT-InSAR agreed with it measured by the wave gage located close to this observation area.

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 Detection of coastal damage due to the 2011 tsunami at Yamamoto Coast was attempted by the state-of-art remote sensing technology using ALOS PRISM satellite images. The digital surface model (DSM) was generated semi-automatically using the remote sensing software EADAS IMAGINE and its accuracy was confirmed by comparing with the digital elevation model (DEM) generated by aerial laser measurement. The coastal damage detected by residual of DSMs before and after the tsunami was verified statistically for each landuse of residential district, rice field, coastal forest, and beach. It was difficult to detect the damage in the low land area where ground objects were scarce; however, it was possible to detect the damage of the coastal forest and residential district. Furthermore, the erosion around seawall could be detected using the DEM instead of the DSM before the tsunami since the former has higher accuracy than the latter.

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 This paper evaluates the fine sediment discharge patterns of rivers in the northern part of Vietnam and the Enshu-nada coast in Japan. The monitoring system was developed based on the MODIS satellite data which has archives for the last 16 years. The system enabled us to capture the different patterns of fine sediment discharge with its relative magnitudes and we found through the monitoring that the amount of turbid discharge in the rivers of the Red River system was reduced while that of the Ma River system tended to be increased. The results of the satellite-based monitoring system present the discharge pattern on a daily, monthly and yearly basis. The daily basis results support the feasibility of the use of the present MODIS-based monitoring system for the investigation of turbidity patterns which may be affected by daily factors such as tides and winds. Monthly or yearly averaged turbidity patterns along the coasts provide us with the additional information of the long-term trends of sediment discharge and the behavior of littoral movement. The results of suspended sediment patterns and their magnitudes are further discussed from a previous study around the Ma river study site. For instance, the decreasing trend of the Red River discharge and increasing trend of the Ma river discharge surely corresponded to the estimated littoral drift based on the analysis of thermoluminescence.

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 In order to estimate blue tide distributions by satellite remote sensing, we carried out a synchronous observation using a ship and GOCI satellite on 24^th. Aug, 2015. In the ship observation, we measured optical properties of the blue tide and Turbidity detected light scattering of sulfur colloids of the blue tide at each station. Based on the observed optical properties and the Turbidity, blue tides estimation model was developed and was applied to a GOCI image to evaluate the estimation accuracy. As a result, the developed model estimated the blue tide distribution of 24th, Aug, 2015 with high accuracy and then it was also capable of estimating blue tide distributions captured in other GOCI images with high accuracy. Hence, the model is expected not only figuring out blue tide distributions but also to be utilized as a monitoring technic for the blue tides.

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 In a wave basin, a multi-directional wave is generated in nearly deep water by a serpent-type wave maker. Its transformations in shallow water are reproduced on a bathymetry model installed in physical, however, its range is restricted with both an area of the wave basin and an applicable model scale considering the scale effect. Therefore, it may be much effective for expanding the wave test area in virtual to generate the transformed multi-directional waves in shallow water. In this study, the serpent-type wave maker is improved to install such a function with a energy balance equation model, and a model experiment of multi-directional wave overtopping on revetments on sloping bathymetry is conducted to show both an effect and a problem of generating the transformed multi-directional waves in shallow water.

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