The problems on restoration activities were extracted from analysis of the past natural disaster cases in port and harbor. They were arranged separately for five important resources to continue business, "person", "facility", "information and communication", "lifeline" and "cooperator". The followings are considered as necessary matters for business continuity in port and harbor; 1) Staff and assistant's roles should be clarified from prior. 2) The feature of business continuity in the port is well understood. 3) Important data of the design data etc. should be kept in two or more places. 4) Temporary depository space of rubbles is secured. 5) It is necessary to examine about the cooperation method of a municipality and related organizations.

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Chile Earthquake Tsunami hit the coastal area of Japan 28 Feb. 2010. In coastal area of Iwate prefecture, an evacuation order was issued and it's reported that only 12.2% of residents had evacuated to the evacuation centers. In order to investigate the evacuation behavior, we carried out the questionnaire survey. The result of questionnaire revealed that (1) Over 60% evacuated respondents went not to the evacuation centers, but to relatives, etc. (2) About 70% respondents went back home before the evacuation order was lifted. (3) Presence of disaster-prevention facility can lower motivation to evacuate. (4) Nearly 20% respondents answered that they will evacuate immediately when next Sanriku earthquake occur.

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We examined values and applications of earthquake and tsunami stone monuments in Tokushima. The results of the study are as follows; (1) the purposes of stone utilization were to hand down records and lessons of earthquake and tsunami to posterity for its "presence", "conspicuousness" and "durability". (2) We recognized three cultural values of earthquake and tsunami stone monuments in Tokushima such as academic material, disaster prevention education material and disaster cultural asset. (3) We found that about 70% of earthquake and tsunami stone monuments in Tokushima have problems of their location and decipherment, and "teaching" function decreased remarkably. On the other hand, some stone monuments signs of their locations and/or explanations in modern Japanese were newly set up. (4) We collected the application cases of the earthquake and tsunami stone monuments in local municipals, areas and primary and junior high schools.

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In this study, the questionnaire researches concerning on the beachgoer's awareness against tsunami disaster were conducted in five seaside resorts where the gigantic tsunami would be attacked when the Tonankai and Nankai earthquake was happened. Many tourists who have less knowledge and information of tsunami disaster visit the study sites. There is a possibility that early evacuation is different for these people. From the results, it is found that the people who live in the prone area to be attacked by gigantic tsunami are aware well of the dangerousness of Tsunami.

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Questionnaire surveys were conducted in the Kushiro City on factors related to evacuation from the Chilean-Earthquake tsunami in February 2010. The factors related to evacuation were veryfied by covariance structural analysis. Although only a small percentage of respondents thought their residence would be flooded or that they would die if they did not evacuate, 42% of respondents actually evacuated. For both respondents who evacuated and those who did not, concern about flooding had a significant influence on intention to evacuate. However, knowledge of the tsunami warning and of the evacuation advisory was not related to concern about flooding.

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Two issues on effects of disaster management consciousness gap by the difference of personal life of the people of Aichi prefecture are discussed. They are (i) effective remote location's great disaster for the people, (ii) quantification of the disaster management consciousness by listening comprehension surveys. Data taken for 46 to 50 areas in Aichi prefecture, 6 inland areas and over 40 coastal areas are examined. In the mean time, a commercial and industrial area characterizes inland area of Aichi prefecture. The results show that (1) it is important that engineers have to view the problem of disaster management from different angles. (2) the disaster management consciousness gap has begun to exhibit obvious symptoms between inland areas and coastal areas.

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A tsunami generated by an earthquake of Mw 7.7 hit North and South Pagai Islands and Sipola Island of Mentawai Islands lying off the west coast of Sumatra Island. This paper reports results of a joint field survey on the tsunami disasters. In the survey tsunami inundation and runup heights were measured in North and South Pagai Islands, and interview investigation was also conducted to understand people's evacuation action in the islands. Averaged tsunami height was about 6 m in the islands, resulting in many losses of human lives and houses. However, there was a good example of evacuation. A person who heard sound of tsunami approaching run to hill with transmitting information of the tsunami coming to other residents, and therefore all residents could evacuate to save their lives.

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The tsunami by the 2011 Tohoku Pacific Ocean Earthquake attacked northern-east coasts of Japan. The main purpose of this paper is to record distribution of inundation heights and run-up heights for improving disaster preventions along north part of Ibaraki prefecture coast, where no accurate records of big tsunami had kept. Water-trace marks and levels shown by witnesses were searched and those heights were measured. There are varieties of results of inundation heights and run up heights along coasts, which means that the tsunami traveled along coast complexly. Though those heights were comparatively good agreements with the information in hazard map provided by local government, the results of inundation area inform that a method to calculate run up of tsunami on land should be modified.

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The 2011 off the Pacific coast of Tohoku Earthquake Tsunami has been observed by the ten GPS buoys of NOWPHAS, drifting on the sea surface at the location of 100-400 meters in depth, on the Pacific coast of Tohoku to Shikoku Districts, Japan. The first tsunami crest of higher than 6 m reached the GPS buoys off the Tohoku Coast approximately 30 minutes after the earthquake. The water level rose relatively slowly in the first part of the first crest and then rose quickly in the latter part. In some locations, the GPS buoy caught the tsunami crest earlier than the nearby coastal wave gauge and tide gauge by several minutes to dozens of minutes. The tsunami was recorded at almost all the tide gauges of NOWPHAS over Japan, including ones on Kanmon Channel and Ariake Bay apart from the Pacific Ocean.

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Coastal damages due to the 2011 Tohoku Tsunami were investigated on the basis of field surveys on the Nakoso Coast, Fukushima Prefecture. Seawall heights, inundation heights, runup heights and ground elevations were surveyed by using VRS type RTK-GPS's. A clear contrast in the damage was identified depending on the height of seawalls; damages were relatively small where the tsunami overtopped the seawall by about 1m while devastating damages including the collapse of seawalls were observed where the overtopped tsunami height exceeded 2m above the crown of seawalls. Disappearance of the sand bar at the river mouth, deformation of barrier islands and tsunami invasion into rivers and the role of coastal forest in damping tsunami flow were also described.

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On March 11, 2011, a large earthquake of magnitude 9.0 took place, generating a tsunami that caused a severe damage to the east coast of Japan. To comprehensively record tsunami trace heights along the coastal region, the 2011 Tohoku Earthquake Tsunami Joint Survey Group was organized. The authors conducted field surveys as a part of this group in Miyagi, Fukushima, Ibaraki and Chiba prefectures. In this paper, the results of these surveys are reported. Inundation heights were more than 10 m in the north part of Miyagi, 5 to 10 m along the coast of Sendai Bay and around 5 m in Ibaraki and Chiba. Buildings, including reinforced concrete structures, were washed away and ships were stranded in land. Coastal structures such as dikes and coastal forests also suffered extensive damage.

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Accurate applicability of hard and soft countermeasures against the 2011 Tohoku Earthquake Tsunami is still under survey. Tide stations located in the coasts were completely washed out and no tide record is obtained in the area devastated by the tsunami with more than 10m height. Only offshore buoy observation data is analyzed employing signal directly stored in memories in the station. Detail tsunami inundation and run up heights were obtained in teams dispatched by the 2011 Tohoku Earthquake Tsunami Joint Survey Group on the March. The paper describes the tsunami heights and hazard characteristics obtained in the coast of Miyagi prefecture, one of devastated areas due to the huge tsunami. Some hints to reduce the tsunami impulsive pressures are discussed.

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Extensive damage was caused by a large earthquake and the resulting tidal wave/Tsunami that occurred in the northeast region of Japan on March 11, 2011. It is essential to be able to understand the extent of Tsunami strike across a wide-ranging area in this type of natural disaster, as rapidly and in as great a detail as possible. In this study, the disaster situation caused by Tsunami in the northeast region of Japan was investigated by the satellite images of the stricken area that had been urgent observed by MODIS and ALOS satellite. The large-scale area of floodwaters in the coastal plain in the southern part of the stricken area was extracted from the land cover classification processing and image interpretation. Especially, it was shown that a zonal region of about 5 km extended the flood area in the inland direction into the plains of the coast region.

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Tsunami has caused devastating damage to coastal regions many times. Since a period of earthquake occurrence generating tsunami can be estimated from historical records, the time of the earthquake occurrence and its magnitude are roughly estimated. Therefore, accumulation of field survey data and knowledge is important to prepare for future tsunamis. In this paper, we examined a simplified chemical analysis of soil to detect the tsunami inundation area and presented an on-site analytical method for inundation area detection. This chemical analysis is expected to support field surveys on tsunami inundation area.

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The authors developed the tsunami fragility curves due to 2009 samoa earthquake tsunami, to investigate structural vulnerability in the affected area, by integrating satellite remote sensing, field survey, numerical modeling, and GIS analysis. In this paper, the authors propose three kind of tsunami fragility curves of structural destruction with regard to the inundation depth, current velocity, and hydrodynamic force.

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Unevenness which is sometimes seen on a nourished sandy beach may induce a serious accident, and therefore checking the safety of the nourished beach in advance is important. In this study, field survey to detect underground caves on an artificial sandy beach has been carried out by using a ground-penetrating radar (GPR) system. Also, in the survey site, more than 10 of unevenness were formed just after a heavy rain in the rainy season of 2010. Therefore, the generation mechanism of unevenness has been investigated by analyzing the locations and the underground structure where the unevenness were formed. The result is that the unevenness had been formed by that the nourished sand had fallen into a space between stones lying under the nourished sand. The mechanism has also been confirmed through a simple experiment.

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This study focused on the morphological change in Alapi beach of Fongafale islet in Funafuti atoll, Tuvalu. Although Alapi beach is indispensable for residents, the mechanism of morphological change is not sufficiently understood because measured data of morphological change are not enough. Measurements of sandy beach's shape in Alapi using handy GPS and wave condition in lagoon were carried out by this study. Analyzed results of measured data indicated that the longshore sediment transport in Alapi beach is toward north through a year and the rare tropical cyclone has potential of rapid both northward and southward transport of sandy beach. This mechanism of morphological change becomes fundamental information for beach conservation plan in Alapi beach.

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This study aims to clarify the topographical classification of fringing reefs and the water circulation structure ("reef-cell") in typical topographic types of coral reefs. Fringing reefs which are well seen in Okinawa can be classified into five types according to the topographical features and physical conditions. Numerical experiments showed that spatial non-uniformity of wave set-up is developed by wave refraction patterns according to reef topography, and resultantly a flow circulation pattern named "reef-cell" corresponding to the geographical features is generated. The unit cell structure in the reef, which is similar to terrestrial watershed, can be established by combining the topographical classification and the hydrodynamic reef-cell characteristics.

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Multispectral remote sensing of coral reef bathymetry by popular Lyzenga et al.(2006)'s method theoretically becomes more accurate with increasing number of bands used. The recently-appeared WorldVIew-2 imagery has doubled number of bands compared with the traditional high-resolution satellite imagery. In this study, we validated the accuracy improvement of Lyzenga et al.'s method by the doubling of bands through its application to five WorldView-2 images of four coral reef sites. As a result, for all the images, the adjusted R squared value of the water depth estimation function improved by doubling the number of bands used, although the degree of improvement (0.003 at the minimum, and 0.097 at the maximum) differed among sites, and even between the two images of a same site.

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Field experiments were conducted from July 14, 2009 to Nov. 2, 2009 to investigate correlation between wave sound pressure levels and wave heights at the Hasaki coast, Ibaraki, Japan. The result revealed that a good correlation can be seen between the significant wave height and the wave sound pressure level. Also, focusing on the significant wave period, the higher wave heights are seen when the wave periods become longer. We suggested an equation of estimating significant wave height with wave sound pressure level and significant wave period. The calculated results show a good correspondence to the observed results (R = 0.83).

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Over the past decade, a considerable number of studies have been conducted on the wave plane distributions by using two video camera images. These studies analyzed azimuth difference of digital images taken by video cameras. The problem of these studies is to find the same element between two images. Generally, they put the targets or tracers in images to solve azimuth difference. This way which comes from Particle Image Velocimetry (PIV) method, is sufficiency to measure waves. However, this method involves difficulties to put the appropriate number of targets or tracers on water surface evenly, which is not reasonable to measure sea waves. We had developed to measure wave profile system using digital cameras. The wave measurement system checked experimental water tank and field measurement waves. As a result of verifications, we found out availability of the technique, which we analyzed the wave digital image without markers

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Instead of the ordinary surveying method, a portable measurement system of 3-D beach topography for monitoring of beach changes was developed. Seasonal beach changes between the foreshore and backshore in response to the seasonal change in wave energy can be measured. The system was applied for the monitoring after the beach nourishment at the Hamamatsu-shinohara coast facing the Pacific Ocean. It becomes a practical method for the measurement of beach changes.

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The Okoshiki Coast in Uto City, Kumamoto Prefecture, Japan, is apparently a typical sandflat with rhythmical variation of multi-bar-trough structure. Multi-channel analysis of surface waves (MASW) was applied to this sandflat; however, the dispersion curves corresponding to the deeper portion could not be obtained by MASW because of a soft intermediate clayey sublayer. The Rayleigh waves generated in MASW survey propagate in the subsoils; however, they significantly attenuate in soft clayey sublayers. In this study, microtremor array measurements (MAM) were additionally applied at some points along the survey array for MASW to improve the accuracy of MASW results at deeper portion. Combination use of MASW and MAM is a useful technique to evaluate tidalfalt stratigraphy with soft sublayers.

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In the Ise Bay, there is a problem of drifting debris. This study examines the validity to use an Artificial Neural Network (ANN) for the prediction of collection position of the drifting debris. The ANN model predicting the positions of debris generation and debris accumulation is constructed by checking suitable input data and ANN parameters and transfer function. The resulting ANN gives good predictions: 1) The fit ratio of the drifting debris generation positions is 83%; 2) The fit ratio of drifting debris accumulation positions is more than 50%; and 3) In front of Yokkaichi city and southward of Centrair (The central Japan International Airport) are the main places where drifting debris gathers.

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The fundamental characteristics of the high-resolution ocean radar system with the VHF band under severe winter conditions in the open sea area were evaluated through the field observations in Wakasa Bay. As the results, over 50 percentage of the detection ratio of the horizontal currents by the radar was confirmed in about half of observational domain. The comparison between the current data of the radar and that of the current meter in one-month observation at the close point to Tsuruga Peninsula showed good correlation with a correlation coefficient over 0.7 and the standard error of 5 to 10cm/s. It was also indicated that the currents from surface to 5m below the surface were mainly driven by the wind fluctuation component of the 25.3 hours with the phase of 30 minutes.

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Sea surface waves had been observed remotely by using a microwave pulse Doppler radar at off Hiratsuka of Sagami-bay. Sea surface conditions are obtained by analyzing Doppler shifts of backscattered microwaves. Rheem has proposed algorithms which estimate wave direction and wave number with two radars. In this paper, we introduce the Rheem's algorithm and another conventional algorithm at first. The conventional algorithm is used to verify and calibrate phase shifts at each measurement points. In order to measure the wave direction reasonably by using the calibrated phases, we have developed a new idea to estimate the wave direction and the wave number. Finally we have shown a possibility that there are four routes where waves reach to off Hiratsuka with discontinuity of distributions of the wave direction.

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In-situ ocean wave measurement is limited for measurements of temporal-spatial evolution of sea surface information. In order to measure surface wave profile, a radar system is one of choice in the field. However, a radar system is limited to measure carrier wave profile. In this study both temporal and spatial ocean surface characteristics were measured by using a X-band radar system and is verified by wave buoy data. Microwave scattering images were analyzed by WaMosII (Wave Monitoring System II) system which transfers spatial surface elevation in a measuring region. Wave parameters such as significant wave height, maximum wave height, peak wave period, wave age are estimated and verified by the buoy data. The radar measurement gives narrower directional spectra than the buoy observation.

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The accuracy of HF radar-measured wave parameters along the coast of GOTO Islands is examined. Doppler spectra were obtained from two radars, measured at Takasaki-bana and Tsuwazaki, in winter (from December 2007 to January 2008). Using Barrick's method(1977), we estimated significant wave heights and periods from hourly Doppler spectra. A comparison of those estimated from two radars shows different wave height. Hence, we calibrated Doppler spectra so that the significant wave height from two radars might become equal height. Furthermore, we applied the calibrated Doppler spectra to a Bayesian method (Hashimoto and Tokuda, 1998). As a result, the wave parameters estimated by Bayesian method were in good agreement with those computed by WAM, and suitable directional wave spectra can be estimated.

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In order to estimate accurately Chlorophyll in coastal area which has high concentrations of SS. Field observations of remote sensing reflectance, SS and Chlorophyll were carried out at 4 stations in the head of Tokyo bay. Proposed model contains a correction term which is determined by ratio of remote sensing reflectance at two different wavelengths. Estimation results from this model and field observation resuls showed a good agreement. The error, when applying the previous model to estimating Chlorophyll, was attributed to the lack of consideration on SS.

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