Nobuhito Mori

[1] At 14:46 local time on March 11, 2011, a magnitude 9.0 earthquake occurred off the coast of northeast Japan. This earthquake generated a tsunami that struck Japan as well as various locations around the Pacific Ocean. With the participation of researchers from throughout Japan, joint research groups conducted a tsunami survey along a 2000 km stretch of the Japanese coast. More than 5300 locations have been surveyed to date, generating the largest tsunami survey dataset in the world. On the S

At 14:46 local time on March 11, 2011, a magnitude 9.0 earthquake occurred off the coast of northeast Japan. This earthquake generated a tsunami that struck Japan as well as various locations around the Pacific Ocean. With the participation of about 300 researchers from throughout Japan, joint research groups conducted a tsunami survey along a 2,000 km stretch of the Japanese coast. More than 5,200 locations have been surveyed to date, generating the largest tsunami survey dataset in the world.

Abstract Based on a weakly non-Gaussian theory, the occurrence probability of freak waves is formulated in terms of the number of waves in a time series and the surface elevation kurtosis. Finite kurtosis gives rise to a significant enhancement of freak wave generation in comparison with the linear narrowbanded wave theory. For a fixed number of waves, the estimated amplification ratio of freak wave occurrence due to the deviation from the Gaussian theory is 50%–300%. The results of the theory a

The influence of global climate change due to greenhouse effects on the earth’s environment will require impact assessment, mitigation and adaptation strategies for the future of our society. This study predicts future ocean wave climate in comparison with present wave climate based on the atmospheric general circulation model and global wave model. The annual averaged and extreme sea surface winds and waves are analyzed in detail. There are clear regional dependences of both annual average and

Acoustic Doppler velocimeter (ADV) measurements are useful and powerful for measurements of mean and turbulent components of fluids in both hydraulic experimental facilities and fields. However, it is difficult to use the ADV in bubbly flows because air bubbles generate spike noise in the ADV velocity data. This study describes the validity of the ADV measurements in bubbly flows. The true three-dimensional phase space method originally developed by Goring and Nikora in 2002 is significantly use

Typhoon Haiyan, which struck the Philippines in November 2013, was an extremely intense tropical cyclone that had a catastrophic impact. The minimum central pressure of Typhoon Haiyan was 895 hPa, making it the strongest typhoon to make landfall on a major island in the western North Pacific Ocean. The characteristics of Typhoon Haiyan and its related storm surge are estimated by numerical experiments using numerical weather prediction models and a storm surge model. Based on the analysis of bes

Abstract Based on Monte Carlo simulations of the nonlinear Schrödinger equation in two horizontal dimensions, the dependence of the kurtosis on the directional energy distribution of the initial conditions is examined. The parametric survey is carried out to obtain the behavior of the kurtosis as function of the Benjamin–Feir index and directional spread in directional sea states. As directional dispersion effect becomes significant, the kurtosis monotonically decreases in comparison with the un

Tropical cyclones generate severe hazards in the middle latitudes. A brief review and applications of dynamical and statistical downscaling of tropical cyclone (TC) are described targeting extreme storm surge and storm wave hazard assessment. First, a review of the current understanding of the changes in the characteristics of TCs in the past and in the future is shown. Then, a review and ongoing research about impact assessment of tropical cyclones both dynamical downscaling and statistical mod

Quasi‐resonant four‐wave interactions may influence the statistical properties of deep water long‐crested surface gravity waves. As a consequence, the wave height exceedance probability can substantially deviate from the expected distribution obtained by assuming that waves are linear. Here the occurrence probability of extreme events recently derived by N. Mori and P. Janssen (2006) is compared with wave tank data, where strong departures from Gaussian behavior are observed. Experimental wave h

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 is assumed as a constant +4K in the global mean temperature from before the Industrial Revolution (c.a. 1850), and the historical climate condition is perturbed by observed sea surface temperature (SST) error. A set of ensemble experiments assesses the impact of low probability phenomena, such as tropical cycl

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 watermarks inside Osaka Bay and along the Pacific. The maximum storm tide recorded by a tide gauge was 3.29 m at the Osaka Tide Station, which is a historical high for Osaka Bay. Coastal flooding consisted of both storm surge and wave run-up in almost all locations, with flooding exceeding 5 m and 12 m

Climate change due to global warming is expected to have major impacts on phenomena such as tropical cyclones (TCs), Baiu, precipitation, and seasonal storms. Many natural disasters in East Asia are driven by TC (typhoon) activity in particular and their associated hazards are sensitive to local-scale characteristics. As such, it is critically important to numerically simulate TC activity (and other phenomenon) on local scales in order to properly assess climate change impacts on natural hazards