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The present study evaluated the compound flood risk of 11 different-sized rivers in the estuaries of the Ise and Mikawa Bays, Japan, using an integrated framework of atmosphere-ocean-river developed in this study. First, the framework was developed by incorporating the river channel into a coupled model of surge-wave-tide to include the interaction of the storm surge runup and river flow. In addition, the framework was validated by the Typhoon Trami (2018)-induced meteorological field, discharge, and storm surge with high accuracy. Then, the time difference between the storm surge and discharge at the estuary (TDSD) was investigated assuming six typhoons with different tracks and similar distributions of intensity and precipitation using Typhoon Hagibis (2019) as a case study. It was found that the TDSD reveals a high positive correlation with the length of the river channel (correlation coefficient: 0.90). Also, the smaller rivers were more prone to simultaneous storm surge and high river flow. The river with the smallest TDSD average in 6 cases of sensitivity experiments was 70 minutes, and it was clarified that the storm surge and high river flow occur simultaneously (within 15 min) in the most severe case (the smallest TDSD case). As a result, it was found that the small- and medium-sized river with a standard deviation of 49.5 minutes has a small TDSD regardless of the typhoon track, resulting in a higher risk of compound flood in comparison to the large-scale rivers with that of 102 minutes.

The 2022 eruption of the Hunga Tonga-Hunga Ha'apai volcano excited an atmospheric Lamb wave, which induced a fast-traveling tsunami. This tsunami was driven by the pressure-forced wave traveling at the speed of the Lamb wave, and thus, was much faster than conventional tsunamis. This was the first case in which ocean bottom monitoring systems widely observed an air pressure-induced tsunami. The observation showed that the pressure-forced wave split after passing the Japan trench. Our simulations show that changes in water depth can amplify or decrease the pressure-forced wave. Simultaneously, an ocean gravity wave is generated due to the conservation of water volume. Because the ocean gravity wave was slower than the pressure-forced wave near Japan, it was separated from, and traveled behind, the pressure-forced wave. We reproduced the waveforms of different splitting stages observed by the stations near the Japan Trench.

Ocean surface wind and wave information is important in a wide variety of areas, such as coastal disaster reduction, offshore structure design, and atmosphere-ocean flux estimation. This study proposed a new method for ocean surface wind estimation from surface wave spectrum information measured by small global positioning system buoys. The concept of this method relies on the assumption that the high-frequency part of the ocean-wave spectrum is proportional to u* f⁻⁴ where u* is the friction velocity and urn:x-wiley:21699275:media:jgrc25175:jgrc25175-math-0003 is the frequency. The determination algorithm for the coefficient of f⁻⁴ was optimized in this study. The wind direction was determined by the wave cross-spectrum, assuming that the wind direction aligns the propagation direction of the high-frequency part of the wave. The proposed wind estimation method was applied to bay and open ocean observations, and the performance of the proposed wind estimation method was similar between the bay and the open ocean. The proposed method improves the wind estimation especially in coastal areas and at high wind speeds in the open ocean compared with the previous method. The performance of the method of the previous study differs between the bay and open ocean due to their spectral shape differences. High-quality wind and wave information can be obtained using the proposed method. If the mass deployment of small drifting buoys covered the global ocean, the information based on the proposed method could be considerably powerful, and could compensate for the weakness of satellite-based wind and wave estimations.

Green infrastructure, utilizing coastal ecosystems, provides a nature-based solution to counteract coastal hazards and rising sea level. Coastal forests, a major type of green infrastructure, are r...

Seawalls are constructed by covering and protecting the sloping seashore ground with concrete plates or blocks. Their purpose is to sustain high waves induced by strong winds and prevent ground erosion, but they often collapse, mobilising different modes of failure, including that of the ground. Nevertheless, limited research has been conducted on ground failure caused by high waves. In this study, a series of novel centrifuge model tests was first conducted to investigate the failure mechanisms of seawalls due to wave propagation, focusing on the failure of the ground. Finite-element analyses were subsequently conducted to explore the failures observed in the model tests and to provide further insight as to the state of the ground leading to failure. Two failure modes were demonstrated to prevail: floating of the covering panel and sliding failure of the ground. In addition, of the possible causes of failure, the following three were identified in the current study: increased unit weight and reduced suction from wetting; enhanced seepage force under the panel and around the toe block during backwash; water pressure on the back of the panel and the landward side of the toe block during backwash.

Intertidal and supratidal coastal boulder deposits (CBD) result from extreme marine inundation on rocky shores. They are important for understanding long-term coastal wave patterns, have predictive value for future events and can support coastal hazard assessment. But they are poorly studied, and their interpretation remains contentious, with debate on whether they record storms, tsunami, or both. In the case of older deposits, uncertainties about paleo-sea level contribute additional uncertainty. These ambiguities impact risk analysis: should CBD data be part of tsunami risk catalogues, or storminess indices? The hydrodynamics and climatology leading to CBD generation are also still uncertain. Two main obstacles to deeper understanding have been identified: a lack of data on CBD worldwide; and discrepant approaches that lead to difficulties in comparing data from different sites. Building community and interaction among CBD researchers, and awareness of CBD as research targets, can help grow our knowledge and tackle these obstacles.ISROC (www.isroc.network)—Inundation Signatures on Rocky Coastlines—is an NSF-funded Research Coordination Network to define the CBD problem chain and identify research gaps by developing a broad and diverse network of researchers. The authors of this paper are the PIs and steering group. We plan to extend the community of researchers, in particular to include underrepresented groups; to facilitate development of standards and best practices for gathering and archiving CBD data; to develop cyberinfrastructure for uploading, visualizing, and analyzing data; and train the next generation of CBD researchers. To do this, we will create opportunities for cross-disciplinary collaboration and exchange. Using CBD to reconstruct coastal inundation history and extreme climatological states is a prime example of convergence research that cannot be solved by one discipline. The network includes geologists, geographers, oceanographers, engineers, hydrodynamicists, geophysicists, climatologists and paleoclimatologists. Activities include meetings, student training and exchanges; sessions in future years at major conferences in geoscience and coastal engineering; consolidation of survey/mapping approaches; building a global database; and user-friendly, fully accessible online data archiving. Understanding past inundation and how CBD form and evolve will both help to quantify present-day risk and will provide guidance for what to expect from future climate and sea level.

Here, we report that adipose‐derived MSC can differentiate into distinct CAF subtypes in vitro depending on the co‐culture conditions used; in addition, we have identified potential CAF markers that may aid in investigating the mechanisms underlying the role of CAFs in the tumor microenvironment., Cancer‐associated fibroblasts (CAFs) are key components of the dense, proliferating stroma observed in pancreatic ductal adenocarcinoma (PDAC), and CAF subpopulations drive tumor heterogeneity and play a major role in PDAC progression and drug resistance. CAFs consist of heterogenous subpopulations such as myoblastic CAF (myCAF) and inflammatory CAF (iCAF), and each has distinct essential roles. However, it is not clear how CAF subpopulations are formed in PDAC. Adipose‐derived MSCs (AD‐MSCs), which possess a high multilineage potential and self‐renewal capacity, are reported to be one of the in vivo CAF sources. Here, we aimed to investigate whether AD‐MSCs can act as precursors for CAFs in vitro. We recorded morphological features and collected omics data from two in vitro co‐culture models for recapitulating clinical PDAC. Additionally, we tested the advantages of the co‐culture model in terms of accurately modeling morphology and CAF heterogeneity. We showed that AD‐MSCs differentiate into two distinct CAF subpopulations: Direct contact co‐culture with PDAC cell line Capan‐1 induced differentiation into myCAFs and iCAFs, while indirect co‐culture induced differentiation into only iCAFs. Using these co‐culture systems, we also identified novel CAF markers that may be helpful for elucidating the mechanisms of CAFs in the tumor microenvironment (TME). In conclusion, AD‐MSCs can differentiate into distinct CAF subtypes depending on the different co‐culture conditions in vitro, and the identification of potential CAF markers may aid in future investigations of the mechanisms underlying the role of CAFs in the TME.

We assess uncertainties in projecting future changes in extreme storm surge height (SSH) based on typhoon data extracted from ensemble experiment results with four sea surface temperature (SST) conditions and three global warming scenarios using a single atmospheric global climate model. In particular, this study focus on typhoons passing around the Korean Peninsula (KP) defined as the region of 32 to 40° N and 122 to 132° E. It is predicted the number of the typhoons affecting the KP will decrease by 4~73% while their strength will increase by 0.8~1.4% under the given future conditions. The locations of genesis and lysis of the typhoons are expected to be shifted towards the northwest and northeast for all ensemble experiment conditions, respectively. However, the extent of their change varies depending on the future SST and global warming conditions. Storm surge simulations were carried out by using predicted typhoon data as an external force. It is found that future SST patterns and climate warming scenarios affect future typhoon characteristics, which influences values of extreme SSH and locations of the vulnerable area to storm surge under the future climate conditions. In particular, the values of extreme SSH and the locations of the vulnerable area to storm surge appear to be strongly influenced by both pathway and frequency of intense typhoons.

This study conducts a probabilistic tsunami hazard assessment (PTHA) and compares two approaches to representing earthquake source variability in the PTHA. The target region is the coast of Zihuata...

A post-event survey of the coastal impacts of Typhoon Hagibis was conducted in the Greater Tokyo and Shizuoka areas. The typhoon’s intensive landfall generated the highest-level storm surges recorded in the study area with a maximum sea-level anomaly of nearly 2 m at the head of Tokyo Bay. Highly populated coastal areas in the inner sheltered part of Tokyo Bay were subject to only minor damage partially because the peak storm surge occurred during a low spring tide. High water levels along the coastline facing the Pacific Ocean mostly measured 4–8 m above the mean sea level, the exception being the Seisho coast, where extreme wave runup reached over 10 m above the mean sea level. The high water levels predominantly caused by energetic swells were comparable with the crest heights of defense structures in a broad range of the study area. The intensive typhoon did not trigger catastrophic flood damage, but caused minor flooding due to wave overtopping, and there was substantial damage to coastal infrastructures along the coast. This paper presents both an overview of and detailed information regarding the coastal impacts of the intensive typhoon along the highly altered coastline with complex geometry.

The direct simulation of inundation in developed urban areas presents a much greater challenge than the more common bare earth simulations that use roughness, which are used in many tsunam...

We analyzed tropical cyclones (TC) based on the theory of Maximum Potential Intensity (MPI) and Maximum Potential Surge (MPS) for a long-term assessment of extreme TC intensity and storm surge heights. We investigated future changes in the MPI fields and MPS for different global warming levels based on 150-year continuous scenario projections (HighResMIP) and large ensemble climate projections (d4PDF/d2PDF). Focusing on the Western North Pacific Ocean (WNP), we analyzed future changes in the MPI and found that it reached a maximum in the latitudinal range of 30–40°N in September. We also analyzed future changes in the MPS in major bays of East Asia and along the Pacific coast of Japan. Future changes in the MPS were projected, and it was confirmed that changes in the MPS are larger in bays where large storm surge events have occurred in the past.

Nonlinear wave focusing originating from the universal modulation instability (MI) is responsible for the formation of strong wave localizations on the water surface and in nonlinear wave guides, such as optical Kerr media and plasma. Such extreme wave dynamics can be described by breather solutions of the nonlinear Schr\"odinger equation (NLSE) like by way of example the famed doubly-localized Peregrine breathers (PB), which typify particular cases of MI. On the other hand, it has been suggested that the MI relevance weakens when the wave field becomes broadband or directional. Here, we provide experimental evidence of nonlinear and distinct PB-type focusing in standing water waves describing the scenario of two counter-propagating wave trains. The collected collinear wave measurements are in excellent agreement with the hydrodynamic coupled NLSE (CNLSE) and suggest that MI can undisturbedly prevail during the interplay of several wave systems and emphasize the potential role of exact NLSE solutions in extreme wave formation beyond the formal narrowband and uni-directional limits. Our work may inspire further experimental investigations in various nonlinear wave guides governed by CNLSE frameworks as well as theoretical progress to predict strong wave coherence in directional fields.

During the Great East Japan Earthquake and Tsunami of 2011, enormous coastal levees collapsed as a result of tsunami overflows. Concrete-covered levees, where concrete blocks are used to protect levees made of soil, showed a specific failure mode in which back slope blocks and internal soils were dislodged. Although several hydraulic experiments have been conducted in an attempt to understand the failure mechanism, the complexity of the failure requires that both hydro-dynamical and geotechnical points of view be taken into account for a deeper understanding. This study uses a centrifuge to identify the failure behavior of levees from those points of view. The centrifuge can reproduce the stress, water pressure, and overflow velocity of the prototype-scale ground. Overflowing at sufficient time periods was produced in the centrifuge by generating differences in water height for seaside and landside areas. The test results showed that the levees collapsed due to a combination of the effect of water flow on the back slope and seepage inside the levees. In addition, the effectiveness of several proposed countermeasures for preventing collapse was confirmed.

We provide a comprehensive analysis of the spatial-temporal changes in the atmospheric-driven major wave climates (easterlies, southerlies, and westerlies) under two different Representative Concentration Pathways, the RCP2.6 and RCP8.5 scenarios for the end-of-the-century (2075–2099). By comparing the projected scenarios with historical conditions, we found that the easterly wave climates will be more frequents in the southwest basins (up to 15%) and the southerlies in the eastern basins (up to 20%). While the westerlies are projected to reduce their presence in the mid-latitudes and intensify for the high latitudes associated with the poleward extratropical circulation. As a result, coastal risk will be triggered in transitional wave climate regions, in addition to the risk induced by sea-level rise and storm wave generated, by spatial and frequency changes in the prevailing wave climates that will reach regions where up to now they have not, impacting future coastal environments.

Even as storm surge risks are increasing, the projections of such risks have an element of ambiguity. Consequently, policymakers find it extremely difficult to design policies to deal with storm surge risks. Therefore, in this study, we have linked the tropical cyclone models and stated preference experiments with decision models to provide a fresh perspective on households’ preferences for storm surge risk mitigation under ambiguity. We have validated households’ choices under the average and worst projections of storm surges and estimated the expected loss reduction, risk premium, and ambiguity premium for storm surge risk mitigation. Our study reveals that households pay disproportionately more attention to the worst case and that the ambiguity premium is not negligible. This leads to an important conclusion that policymakers should factor in the ambiguity premium to formulate risk mitigation policies.

This paper presents a multivariate classification of the global wave climate into types driven by atmospheric circulation patterns. The primary source of the net long-term variability is evaluated based on historical wave simulations. Results show that the monsoon, extratropical, subtropical, and polar wave climate types of the Pacific and North Atlantic Oceans are dominated by natural variability, whereas the extratropical and subtropical wave climate types in the Indian Ocean, and the tropical wave climate types of the Atlantic and Pacific Oceans exhibit a global warming signal. In the Pacific sector of the Southern Ocean, strong natural variability may mask a global warming signal that is yet to emerge as being statistically significant. In addition, wave climate teleconnections were found across the world that can provide a framework for joint strategies to achieve the goals of climate adaption for resilient coastal communities and environments., 地球全体の波浪特性の変化傾向と自然変動の関係を解明 --地球温暖化の沿岸域への影響を定量化--. 京都大学プレスリリース. 2021-06-15.

A 34-year high-resolution ocean surface wave climate hindcast around Japan is presented, and the wave climate around Japan is examined from a spectral point of view. The spectral wave model is forced by the sea surface wind data obtained from the JRA-55 atmospheric reanalysis. The wave climate hindcast is validated by comparing it with buoy observations around Japan. The correlation coefficient of the significant wave height is 0.9. The correlation coefficient of the mean wave period is 0.8 for the Japan Sea and Pacific side of eastern Japan and 0.7–0.8 for the Pacific side of western Japan. The wave climate is represented by temporal-mean two-dimensional wave spectra. The characteristics of the spectral wave climate are investigated by classifying them into three types. Distinctive characteristics of the mean wave spectra along the Japan Sea are narrower band widths for both the period and direction. The mean wave spectra along the Pacific side of eastern Japan are characterized by swells with a spectral peak propagating from the northeast. The distinctive spectral features corresponding to the Pacific side of western Japan are bi-modal peaks with long-period components typically generated by typhoons. The variability in the monthly mean wave spectra is examined using an empirical orthogonal function (EOF) analysis. In the winter, it is found that the wave height variability (EOF 1st mode) is related to wave direction variability (EOF 2nd mode) at locations 1000 km apart via the sea level pressure variance over the North Pacific. In the summer, the EOF 1st mode corresponding to the Pacific side locations is dominated by the variability in typhoon-generated swells. The spectral wave climate representation provides new insight into the wave climate around Japan with clear relationships between the atmospheric conditions, the wave height, direction, and period.

In this study, the impact of climate change on wind and wave characteristics has been assessed using super-high-resolution MRI-AGCM3.2S wind data and numerical modeling over the Indian Ocean. Wave characteristics were generated in two 25-year periods covering historical and future projections (RCP8.5), and the assessment indicated that, generally, the spatial distributions of wind speed, significant wave height (Hs) and mean spectral wave period (Tm01) will not dramatically change in the future. The assessment also indicated that the wind direction reversing pattern during monsoons will remain similar. Moreover, future westerly winds in the Southern Indian Ocean (SIO) will shift to the south and a decrease in future wind speed north of the equator will occur, espearound the equator due to cially during winter. The relative change of Hs will be less than wind speed the predominance of swells transferring from the SIO. There will be no considerable change in the future Tm01, except during autumn in the area north of the equator. A novel climate stability index is suggested showing that the semi-enclosed seas in the NIO and the western coasts of India and the Maldives will be areas with the least stability in terms of wave climate. Despite experiencing more intense wind and wave climates, the overall climate will be more stable in the SIO than the NIO.

Typhoon Jebi in 2018 caused severe damage along areas of Osaka Bay, Japan. After the storm, a Japan Society of Civil Engineers (JSCE) coastal survey group surveyed the coastal impacts and recorded ...

This study examines long-term ensemble projections for historical and future climate conditions over 5,000 years using an atmospheric global circulation model. The future climate condition ...

Hurricanes Irma and Maria caused catastrophic damages across the Caribbean Islands during the 2017 hurricane season. After the storms, a joint United States–Japanese team investigated coastal impac...

This study assesses the long-term impact of storm surges due to typhoons around the Korean Peninsula (KP) resulting from climate change. Long-term projection is conducted based on the large ensemble experiments on so-called d4PDF for the past and +4 K future climate conditions over 5000 years by a single atmospheric global climate model developed by the Meteorological Research Institute of Japan. The use of a large ensemble is to enable one to obtain probabilistic future changes in low-frequency of extreme storm surge events. The properties of typhoons which may directly and indirectly have an effect on the KP in terms of past and future climate conditions is extracted from d4PDF. These are employed as the driving force in the projection of future storm surges around the KP. The storm surge heights (SSH) around the KP are projected to increase in the future climate except for around some areas in the south coast. The magnitude of future change of SSH varies spatially. The maximum variation was estimated to be 0.36 m (9.9%) with a 100-year return period in the west area of the southeastern coast of the KP. The locations of the areas vulnerable to storm surge shift to the north area of the western region and to the west area of the southern regions in the Korean Peninsula under the future climate. The characteristic of future change to areas where high SSHs will occur coincides with that of the typhoon tracks.

Artificial vascularized tubular liver tissue has perfusable blood vessels that allow fluid access to the tissue interior, enabling the injection of drugs and collection of metabolites, which are valuable for drug discovery. It is amenable to standard evaluation methods, such as paraffin-embedded sectioning, qPCR, and RNA sequencing, which makes it easy to implement into existing research processes. However, the application of tissues vascularized by the self-assembly of cells, (including tubular liver tissue, has not yet been tested in comprehensive proteomic analysis relevant for drug discovery. Here, we established a method to efficiently separate cells from the tubular liver tissue by adding a pipetting step during collagenase treatment. By using this method, we succeeded in obtaining a sufficient number of cells for the proteomic analysis. In addition, to validate this approach, we compared the cells separated from the tissue with those grown in 2D culture, focusing on the proteins related to drug metabolism. We found that the levels of proteins involved in metabolic phases II and III were slightly higher in the tubular liver tissue than those in the 2D cell culture. Taken together, our suggested method demonstrates the applicability of tubular liver tissue to the proteomic analysis in drug assays.

Developing an effective tsunami evacuation plan is essential for disaster risk reduction in coastal regions. To develop effective tsunami evacuation plans, real transportation network, interaction among evacuees, and uncertainties associated with future tsunami events need to be considered in a holistic manner. This study aims to develop such an integrated tsunami evacuation approach using agent-based evacuation simulation and advanced stochastic tsunami hazard assessment. As a case study, a urban area in Padang, Indonesia, threatened by tsunamis from the Mentawai–Sunda subduction zone, is adopted. The uncertainty of the tsunami hazard is taken into account by generating 900 stochastic tsunami inundation maps for three earthquake magnitudes, i.e. 8.5, 8.75, and 9.0. A simplified evacuation approach considering the evacuees moving directly to evacuation areas (defined a priori) is compared with two more rigorous agent-based modeling approaches: (a) a two-destination-point tsunami evacuation plan developed by the local government and (b) a multiple-destination-point plan developed in this study. The improved agent-based stochastic tsunami evacuation framework with multiple destinations takes advantage of the extensive tsunami hazard analyses to define safe areas in a dynamic manner and is capable of capturing the uncertainty of future tsunami risk in coastal areas. In contrast, the results clearly show that the simplified approach significantly underestimates the evacuation time, and the existing tsunami evacuation routes identified by local authorities may be insufficient to save lives.

This study developed an integrated model for the long-term assessment of extreme storm surge heights based on the maximum potential intensity (MPI) of a tropical cyclone, which is used to conduct future climatological projections of maximum potential storm surge height (MPS). We apply the MPS method to three major bays in Japan, Tokyo, Osaka, and Nagoya, using two mega-ensemble climate change projections: CMIP5 and d4PDF. The sensitivity of MPS change relative to sea surface temperature (SST) change for three major bays in Japan is about 0.12 m/∘C during tropical cyclone season, which is about 1/10 of the change when considering SST rise only. Both the mean and variance of future MPS values will be much greater, especially in September and under higher representative concentration pathway (RCP) scenarios.

Hindcasts of the downscaled fine resolution scale coastal dynamics are important to quantitatively analyze variations in storm surge heights, water temperature, salinity and high velocities which induce shoreline changes. This study quantifies the impact of two extreme storm surge events in October 2006 on the Ibaraki Coast in Japan to the coastal Sea Surface Height (SSH), vertically averaged velocity (Vbar), Sea Surface Temperature (SST) and Sea Surface Salinity (SSS) by reproducing hindcasts of the dynamically downscaled coastal dynamics from a 10 km resolution parent dataset (Four-dimensional Variational Ocean ReAnalysis for the Western North Pacific over 30 years, FORA-WNP30) to related 2 km, 667 and 222 m resolution datasets using 3 domain nesting Coupled-Ocean-Atmosphere-Wave-Sediment-Transport Modeling System (COAWST). Validation was made by comparing the SSH, Vbar, SST and SSS modelled results with observed data and discussing differences in their values in the downscaled and the parent datasets. This study concludes that the low-pressure system event on 7th of October had much bigger impact to the SSH and Vbar than the one on 24th of October, which had similar peak of southward surface wind but lower Sea Level Pressure drop, whereas the impact to the SST and SSS was similar. These findings are helpful in understanding and assessing shoreline changes and damages on the well-developed local fishery and seashell industry. Finally, these findings and modelling approach are useful for climate change impact assessment and can ultimately serve as guidelines for developing adaptation policies.

Raman scattering represents the distribution and abundance of intracellular molecules, including proteins and lipids, facilitating distinction between cellular states non-invasively and without staining. However, the scattered light obtained from cells is faint and cells have complex structures, making it difficult to obtain a Raman spectrum covering the entire cell in a short time using conventional methods. This also prevents efficient label-free cell classification. In the present study, we developed the Paint Raman Express Spectroscopy System, which uses two fast-rotating galvano mirrors to obtain spectra from a wide area of a cell. By using this system and applying machine learning, we were able to acquire broad spectra of a variety of human and mouse cell types, including pluripotent stem cells and confirmed that each cell type can be classified with high accuracy. Moreover, we classified different activation states of human T cells, despite their similar morphology. This system could be used for rapid and low-cost drug evaluation and quality management for drug screening in cell-based assays.