Climate variabilities in characterictics of typhoon, annual precipitation and SST are investigated in connection with the indecies of atomospher- ocean interaction such as MEI, PDO, NAO and AO. Spectra of annual time serries of the climate indecies were analyed to find a relationship between the climate change and the indecies of ocean-atmosphere interaction. A five-year variation in an annual mean minimum pressure of typhoon is found to have the same period of MEI and about one year time lag. The other climate indecies are found to change with the indecies of large-scale atmosphere-ocean interaction, such as MEI and PDO. The activity of typhoon and climate valiations are estimated employing linear system analysis with the impulse response functions and are compared with the measured climate data.

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When we introduce a plan or the designs on the coastal prevention institutions which considered adaptation to the climate change, we cannot avoid that we set amout of the sea level rise to date. It is assumed that we decide the amount of existing surface of the sea rise to reflect for a plan / a design and argues by the analytical method of the data at each stage. We assume the previous rise 3.1mm/year of IPCC AR4 mention basics, and what we match it with the situation of the frontage and adjust is rational.

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The emission of CH₄ and N₂O from mangrove plantation area were important for evaluation of carbon stock in an implementation of a mangrove CDM project. Emission rate of CH₄ and N₂O from non-mangrove ecosystem (wetland and fresh water et. al) for mangrove plantation area were from -90 to 36648 μmol CH₄ m^-2 day^-1, from -41 to 499 μmol N₂O m^-2 day^-1. Discrepancies exist in the emission of CH₄ and N₂O obtained from the other ecosystem due to environmental condition (high loading and salinity). We estimated emission of CH₄ and N₂O from our planted mangrove area in Vietnam by observed data, which suggests that total emission of CH₄ and N₂O from mangrove ecosystem was approximately 10-20% of total carbon stock in mangrove forest over 21 years integration from a mangrove plantation.

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The residents in Ohsima district, Karatsu city are being afflicted with the blown sand generated from stock yard. The purpose of this study is to propose new countermeasures to decease blown sand through the wind tunnel experiments and the numerical simulations. The experiments revealed that the upward extension of the present shield fence is most effective to decrease the flux of blown sand. The height of the most effective fence was decided by using the numerical simulations. As a result, it is shown that the 20 m shield fence is the most effective in Ohsima district.

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In wave-power generation, it is important to clearly identify the running-up characteristics of irregular waves, because the facilities are installed in actual marine waters. The experiment was conducted using a two-dimensional wave-making channel of 52.0 m in length, 1.0 m in width, and 1.5 m in depth. A model scale of λ =1/25 was used taking into account the size of the experiment facility, wave-making capacity, wave conditions, etc. The results showed that gentler slopes tended to cause breaking waves, while steeper slopes tended to cause surging waves, and that the difference in wave forms influenced the run-up height of waves. Slopes created the most efficient run-up waves when cotθ=2.75 (20°).

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We have developed a way of harvesting electrical energy from the ocean power, e.g. tide, current, wave, breaking wave and vortex, using a flexible piezoelectric device consisting of piezo-electric polymer film (PVDF), silicon and natural rubber. The flexible piezoelectric device (FPED) is a hydro-electric ocean energy unit designed to convert renewable energy harnessed from ocean energy into usable electricity. The basic concept generating electric power using FPED is to utilize fluid structure interaction, e.g. flattering, flapping and periodic bending, caused by ocean energy. The FPED deformed by kinetic energy of the ocean power stores elastic energy and also converts it to the electric energy. We carried out some experiments using wave tank and the water tunnel with a bluff body. We have confirmed the electricity generated by wave, current and vortex using the FPED.

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We have developed a new wave power generator using flexible piezoelectric device (FPED) which is a hydro-electric ocean energy unit designed to convert renewable energy harnessed from ocean energy into usable electricity. In our previous works, the FPED consisting of piezo-electric polymer film (PVDF) is a way of harvesting electrical energy from the ocean power, e.g. tide, current, wave, breaking wave and vortex. The concept of this study is that existing coastal and ocean structures (i.e. a breakwater, submerged obstacle, reef in shallow water and submerged plate in deep water) are utilized as a wave power generator sticking with the FPED to make a safety and disaster prevention. We examined the usefulness and electric performance of the FPED deformed by waves in experiments.

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Most of hydroelectricity development represented by the dam in our country has almost completed. In comparison with it, the use of ocean energy generation is still a development stage. For this reason, we aim at development of the small hydroelectricity device using a piezo-electric element, it will harness Kármán vortex street which occurred by put the object in flow. In this paper, we perform basic examination by numerical simulation and hydraulic experiment about the relationship between Kármán vortex street and the object shape in flow, and vortex-induced vibration. Then we will make generation experiment based on its results, and suggest suitable model of generation.

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In connection with a planning of fishing ground development in the exclusive economic zone around Hokkaido, the authors observed currents, water quality, plankton and the primary productivity in the area surrounding the Musashi Bank in August in 2009. As a result, the primary production rate of summer of this sea area was estimated to be about 36.6 (mg-C/m²/day). It is quite lower than that of other bay area in Japan. The density stratification was observed and it suggests that Tsushima Warm Current along the Hokkaido coast influences the height of the layer. Depth in which it meets the requirement of the photosynthesis is 25-55m. It accounts for about 66% of the primary production of the entire water column here. It was confirmed that the lack of the nutrient salt on the surface limited the primary production of this sea area in summer.

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The stratification of upper layer of coastal water can be regarded as an unused energy source in summer. The coastal water has large capability to store the urban heat owing to the heat capacity difference between the air and water. The estimated urban heat over Sumiyoshi ward in Osaka is equivalent to 10 m³/s warm water if we allow 7 degree water temperature increase from stagnant environment. The numerical simulation of the urban heat release into coastal zone is performed. The larger warm water discharge gives absorption effect of short wave radiation from the atomsphere to the ocean due to enhancement of vertical mixing of upper occean.

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A numerical simulation model for storm surge inundation has been developed. Inundation simulation method induced by transition process from overtopping to overflow is incorporated into this model. Convenient estimation method for this transition process is based on the equations produced by Goda(1975a). Several parameters in the Goda's equations are revaluated by numerical wave simulations of the transition process from overtopping to overflow. These simulations are performed by using VOF method (CADMAS-SURF). According to these simulation results accurate flow rates over the coastal dikes are estimated at the time of storm surge. With this simulation model high storm surges generated by large typhoons around the coasts of Japan can be reproduced. This paper presents the outline of the simulation model for storm surge inundation.

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We examined tsunami evacuation at the 1854 Ansei and the 1946 Syowa Nankai earthquake and considered factors to urge early tsunami evacuation. The results of the study are as follows; (1) There was a problem in tsunami evacuation because 60 percent or more of the deceased person originated in the tsunami at the 1854 Ansei and 1946 Syowa Nankai earthquake. (2) There were a lot of people who evacuate early from the tsunami at the 1854 Ansei Nankai earthquake because they experienced in "small tsunami" at the 1854 Ansei Toukai earthquake. (3) Inhabitants were able to decrease deceased persons because they had evacuated early from the Syowa Nankai earthquake tsunami. In addition, a factor to urge early tsunami evacuation they knew legends that concretely urge evacuation from tsunami.

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In order to estimate human loss caused by tsunamis, we proposed the method in consideration of resident's evacuation process that affected human behaviors and loss greatly. The process can be divided into three steps after earthquake, which could be modeled in this study. Factors affecting the evacuation can be statically clarified through the questionnaire survey of the evacuation process. And we evaluated the effective method and proposed the developed human loss evaluation method considering a local evacuation characteristic. Finally we applied it and carried out the evaluation of human loss in the target area

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To reduce the casualties by tsunami around seaside, it is necessary to investigate the process of decision-making and evacuation of beachgoer against tsunami disaster. This is the objectives of this paper. By using the method of covariance structure analysis, the dominant factors of decision-making were discussed with 1173 questionnaire sheets answered in four seaside resorts. The result shows that knowledge of tsunami closely relates to awareness of one's evacuation, and then it derives the evacuation volition from the awareness. Evacuation simulations were studied for one of the beaches by using the cellular automaton method. Then, it is found that evacuation guidance is very important in early evacuation.

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This research aims to discuss a possibility of tsunami early warning system with the observation of hydro-acoustic waves (T-phase) caused by sudden sea-bed disturbance by a fault rupture. The authors derived an analytical solution of sea surface disturbances of slightly compressible ocean when the limited width of sea bottom is uplifted on a uniform slope to push up overlying water with the speed of V₀ and within the time duration of τ. Based on the analytical solutions obtained, we discuss the relationships between T-phase characteristics and the seismic parameters of rupture width, rise time and rupture velocity.

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The marine litter drifted on the coast is expected to affect coastal environment and ecosystem. However, its year-round behavior still remains poorly understood. In this paper, we examined the spatial distribution of the drifted litter from 23 rivers to the Seto Inland Sea and influence of the seasonal wind or river discharge on the drifting process of the litter in the Seto Inland Sea by semi 3-D FEM numerical simulation model. Moreover, we also carried out field observations in the Narugashima Island which is located at the southeastern part of Seto Inland Sea. It is clarified the source of most litter (golf ball or cigarette lighter) is the river basin in the Seto Inland Sea, however, some of them were reached from nearby Asian countries.

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In this study,we discuss about an evaluation method of restoring nature planning involving a reformation of breakwater. We have proposed PHSI(Probabilistic Habitat Suitable Index) model for evaluation method of marine environment by reforming breakwater. In this paper, we focus on the growth rate of children of stony coral (Acropora tumida) in two different PHSI points. We understand the relationship between PHSI value and the initial amount of coral growth. Then we evaluated to consider restoring nature plan from the initial amount of coral growth. PHSI value differs by 0.1, about three years, the amount of coral growth was found roughly 170% of the difference may occur.

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Impact of rise in sea-level due to global warming and positive population growth derive primary vulnerability in coastal zones. On the other hand population has been decreasing especially in rural area of Japan so that a change in a risk of coastal disasters depends on the competition between sea-level rise and negative population growth. This study carried out a vulnerability assessment of coastal flood with these compound impacts which agreed to SRES scenario of IPCC in 21^st century. After future population in the target area was calculated this population was adjusted to the trend of SRES scenarios. The time-series of flooded area and that affected population according to each scenario were counted and adaptation strategies were discussed for thinly populated areas.

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On 11 August, 2009, at 05:07 JST, a moderate-to-large earthquake struck two deep ocean water pipes, which reach 397 m and 687 m deep at Suruga Bay in the near-field. We carried out two surveys by using R/V Natsushima and ROV Hyper-Dolphin for better understanding of damage of the water pipes and its cause. The first survey was done by using ROV Hyper-Dolphin, which contained the visual surveys. We have realized that the 687 m water pipe has been flowed at least 2 km away from the original laid position. The second survey using R/V Natsushima was done in order to reproduce the bathymetry map in the source area. We could discover an erosion pattern created near the 687 m water pipe, whereas a sediment pattern in the downstream, which is possibly a submarine landslide evidence caused by the earthquake.

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An earthquake of Mw 8.8 struck off the coast of central Chile on Feb. 27, 2010. A tsunami due to the earthquake propagated on the Pacific Ocean and attacked Japan on the next day. JMA issued a major tsunami warning for many coastal regions, however severe damage occurred in many ports especially for fishery. To understand the tsunami disaster, the filed investigation was carried out to record tsunami heights such as run-up heights and inundated heights along the comprehensive coastal region. In cooperation with many institutes, eyewitnesses interview, measurement of tsunami trace and analysis of tide records were conducted. Then the tsunami height distribution from Hokkaido to Okinawa is reported here. The tsunami was higher in the northern part of Japan and it exceeded 2 meters in the Tohoku district especially.

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A great earthquake (Mw 8.8) occurred offshore at central Chile on 27, Feb., 2010 in Japan time. Tsunami by this earthquake arrived at the Pacific coasts of Japan 22 hours after the occurrence. We surveyed the Tsunami Trace Height (TTH) and arrival times along the coast in the Kanto and Tokai districts. As a result, the TTHs were lower than 1.8 m and the arrival times were basically from 16:00 to 18:00. Along the surveyed coasts, the TTHs from the 1960 Chilean tsunami were 1 to 3 m, generally higher than the 2010 TTHs. However, at a few locations, the 2010 TTHs were locally similar or slightly higher than the 1960 TTHs.

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The present paper reports a preliminary result of searching tsunami-affected area using recent advances of GIS analysis and remote sensing combined with a numerical modeling of tsunami propagation/inundation and world population database. Applying the method of searching tsunami affected area to the 2010 Chilean earthquake tsunami, the potential tsunami affected area have been detected at some coastal cities/communities from Biobio to Maule regions.

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The authors propose a method to search and detect the impact of tsunami disaster by integrating numerical modeling remote sensing and GIS technologies. This method consists of regional hazard/damage mapping identifying exposed population and satellite image interpretation in terms of structural damage. The method is implemented to the recent tsunami event the 2009 tsunami in American Samoa to identify the structural damage by the tsunami.

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A field survey of the 2009 Samoa earthquake tsunami was conducted on Tutuila Island, American Samoa, within a week of the event. At the western end of the island, the largest runup height was measured to be 16.3 m and almost all buildings were completely destroyed and/or washed away. In the east, runup or inundation heights were smaller (2-6 m), but buildings were severely damaged. At Pago Pago, main town of the island, inundation heights were around 4.5 m, and inundation limit is about 600 m from the coastline. The tsunami arrived 5-10 minutes after the mainshock. The death toll was low, because federal and territorial governments had together carried out an extensive public education program to explain tsunami hazard.

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A large tsunami attacked Tutuila Island, American Samoa in the early morning on 29 September 2009 (local time), and killed 35 people. We must draw attention to be low death ratio compared with past tsunami disasters, while local people did not get tsunami warning information before tsunami coming and did not have tsunami knowledge. We carried out the field investigation on evacuation behavior of residents in Tutuila Island. The main findings are as follows: first, most residents evacuated some high ground areas close to their residential area. Secondly, almost all people evacuated on foot. Third, residents built social reality "We are dangerous when we are here". The reality was built by some people's behavior, e.g., mayor's call, residents' call, sounding the church bell and so on.

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This paper aims to understand the characteristics of the tsunami disaster in the Samoan Islands by analyzing the field survey data as well as numerical simulation results. The field survey was performed about one month after the disaster to clarify the tsunami wave height and to understand the reality of the disaster according to the residents. As a result, the followings are concluded. 1) Tsunami height exceeded 5m in a wide area of Upole and Tutuila Islands. 2) In areas that have a wide coral reef, people saw the wave breaking on top of it and quickly became aware of the approaching tsunami. 3) Tsunami education contributed the residents' reaction on the evacuation. 4) Social characteristics especially existence of Matai (the chief of the village) influenced the residents' decision making after the tsunami disaster.

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Caldera harbor located in the Pacific coast of Costa Rica in the Central America was contracted in early 1970' and has been operated as one of the most important international cargo-handling port in the country. Heavy sedimentation and accumulation in the harbor have been observed since opening. In order to prevent the sedimentation, a breakwater was extended to the offshore and dredging in the anchoring area was occasionally carried out. A large storm destroyed the top of breakwater by 60m in 2004 and the water depth in front of a berth became shorter than initial. In order to keep the operation of port, evaluation of volume of sedimentation drifted into the anchoring area and reinforcement of damaged breakwater is necessary. Analytical and field survey to resolve such subjects were done in international collaboration.

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Time-space distributions of the internal velocity were measured in Ariake Sound using Lagrangian-Acoustic Drogue for Intertidal environments (LAD-IT). The turbidity distributions were calculated using backscattering data of ADCP by solving the sonar equation. Time-space distributions of both the eddy viscosity and eddy diffusion coefficients were estimated using those of both the velocity and the turbidity. The estimated results indicated that the both coefficients changed temporally and spatially. The order of magnitude of the eddy viscosity was 10^-3-10^-2 and that of the eddy coefficient was 10^-5-10^-4. These orders were in good agreement with the conventional studies. The results indicate LAD-IT is adequate for estimating time-space distributions of eddy viscosity and eddy diffusion coefficients in the field.

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The prototype of colored sand analysis system, which uses high-speed and high-precision colored sand measurement and is based on a high-speed image analysis, was developed for sediment dynamics monitoring. Its reliability and usefulness were verified by introducing to the developed system, a new method of density measurement of colored sand by color discrimination method. By using this system, it has become possible to observe sediment dynamics on a high-frequency, short-term basis. As the investigation of coastal erosion and other phenomena progresses rapidly, it has been confirmed that the system provides practical techniques for sediment flux management.

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in the present study, the effectiveness of the Mapping method was verified. As a result, even the investigator who doesn't have expertise of the NPO group and the student, etc. by the proper move method can investigate, and the area was able to understand about 0.7km² wide-ranging one in two weeks. In addition, the adjustment with the water quality investigation result of the execution of the municipality was able to be taken, and acquired data was able to be judged to be a valid result. On the other hand, because GIS is used about the management of data, it doesn't become the one that everyone can treat. Therefore, this Mapping method was devised for the possibility that the part was able to be borne to exist now at the time of having not established it by the monitoring methodology that continued in a mid/long term though future tasks were left in this part.

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Recently, the quantitative evaluation in the effect of the primary production of the artificial upwelling producing structure is tried by using a primary ecosystem model. In this case, it is important to understand the sinking flux of the particle organic matter because of the supply of the organic matter to the structure neighborhood and the reproducibility verification of the model. Then, the field observation that used the sediment trap to understand the behavior of the particle organic matter was done for the artificial upwelling producing structure in Nagasaki Prefecture. As a result, the sinking flux tended to increase relatively in the sea area where the upwelling was generated. Moreover, the big zooplankton etc. that did not sink were contained in the sample in the sediment trap by the influence of the formalin solution by about 33 percent.

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Most of the artificial intertidal flats are filled with dredged clay and have a sand capping. Immediately after the construction, because the dredged clay has not consolidated, a safety assessment system is strongly required to avoid a person who is caught in a soft clay layer at a place where sand capping is significantly thin. The authors have applied MASW method to various types of intertidal flats, and confirmed that the MASW is very useful method to efficiently survey the stratigraphy of intertidal flats. In this study, the MASW was applied to three intertidal flats: an artificial flat which was immediately after the filling; an artificial flat which was about ten years after the filling; and a natural muddy flat which has deposited over many years. Through these investigations, it was confirmed that MASW technology is useful to evaluate the safety of artificial intertidal flats.

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A Modified Bayesian method (MBM) for estimating directional spectra from the Doppler spectra obtained with HF radar is examined using data acquired during the SCAWVEX project. Applicability, validity and accuracy of the MBM are confirmed compared with the directional spectrum observed with a directional buoy. Some assessment studies of a boundary condition are examined to be given at the lowest frequency of directional spectrum so that a suitable directional spectrum can be estimated. The results clearly demonstrate that the directional spectra can properly be estimated without losing its applicability and practicality for estimating directional spectra from field data.

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A new technique for estimating spatial distribution of oceanic waves using polarization ratio data of PALSAR synthetic aperture radar is presented. Polarization ratio of the backscatterd power from the ocean surface at vertical to that at horizontal polarization (VV/HH) is closely correlated to the local incidence angle which reflects local water surface slope. At first linear relationship between incidence angle θ and polarization ratio P was derived from the trend of the entire target aria. Then the pixels on the polarization ratio image correspond to the steepest slope points were selected with reference to the HH backscatterd power image. The mean steepest slope of ocean surface was estimated from the selected pixels and the linear relation between θ and P. Finally, assuming sinusoidal waves, mean wave height was estimated from the steepest slope and mean wave length estimated from the HH image. This method was applied to each divided 3x3km subareas and spatial distribution of wave height was estimated.

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The authors developed a method of object-based satellite image analysis using high-resolution post-tsunami satellite image to detect and map tsunami impact. The method is applied to QuickBird 4 band pan-sharpened composite image acquired in Banda Aceh, Indonesia, and the ground objects are classified into six ; vegetation, water, soil, building, road and debris, for mapping the impact of the 2004 Sumatra-Andaman earthquake tsunami.

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Using a capability of SAR(Synthetic Aperture Radar) image analysis, the authors develop a method for mapping tsunami affected area, focusing on the relationship the backscattering features between pre and post-event SAR images. The method was applied to Aonae district in Okushiri island which was the most devastated by the 1993 Hokkaido Nansei-oki earthquake tsunami (Okushiri tsunami) to identify the the severity of structural damage with a fragility curve of pre-post SAR image features and probability of structural destruction.

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Surface current velocities have been measured with shortwave ocean radar systems in Ise Bay and Mikawa Bay since 2007. This study presents the seasonal surface flow in the both bays by using the ocean radar systems and the full-3D numerical simulation model. The main results are summarized as follows. Specific circulations do not appear in Ise Bay. The southward current from closed-off of Ise Bay flows the Chita Peninsula side all the year round. The southward current meanders in the southern part of Chita Peninsula due to the salinity front. A week clockwise flow existed at the central part of Ise Bay. The characteristic of seasonal surface flow in Mikawa Bay is the same as previous studies.

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A passive remote sensing method of relative depth (a variable proportional to water depth) of shallow water is proposed. It is similar in the prediction formula with the well-known regressive method by Lyzenga et al.(2006), but is unique in that it doesn't require any auxiliary input data other than single multispectral image: the coefficients of the formula is estimated by utilizing pixels of near-zero depth extracted from image, without relying on in-situ measurements of water depth or other optical properties. The accuracies (correlation coefficient between estimated and measured depth) of the both methods are tested using a QuickBird image of a coral reef area. As a surprising result, the accuracy of the new method is found to be comparable and sometimes even superior to that of Lyzenga et al.'s method.

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The spatial structures, tidal current amplitudes and phases, of M₂ tidal ellipses in the Northern part of Osaka Bay are estimated by using two set of observation with Ocean Radar Systems which measured the surface velocities in the western and the eastern area of Osaka Bay during around January and November 2003. The area of M₂ tidal ellipses estimated with two set of observation is 1.3 times as wide as the total area of that with each observation. The spatial averaged precision of the former velocities is expected about 3 times more accurate than that of the later velocities.

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An upgraded submerged Doppler-type directional wave meter can measure 10wave quantities related to directional wave motions, i.e. water surface elevation, 3 components of water particle velocities at each layer of 3different water depth ranging from shallow to deep. In this study, accuracy of directional spectrum estimation is comprehensively investigated for various cases where directional spectra are estimated with various sets of different number of wave quantities. As a result, accuracy improvement is generally confirmed in various wave conditions when all the quantities are applied to the estimations, compared with the cases where conventional 4 wave quantities are applied to the estimations.

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The ecological breakwater constructed at Mishima-Kawanoe Port in Ehime Prefecture in 2005. This study presents results of questionnaire surveys using Contingent Valuation Method (CVM) and Fuzzy Structural Modeling (FSM) method relevant to Willingness to pay (WTP) of Eco-breakwater. The structure of the various effects of Eco-breakwater is established by FSM method, which is an equation of calculating the total WTP of various effects by eliminating double counts. The B/C ratio is calculated as more than 7.0 by using CVM and FSM method, showing social significance on installation of Eco-breakwater.

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