Storm surges cause coastal inundation due to setup of the water surface resulting from atmospheric pressure, surface winds and breaking waves. Here we show that during Typhoon Haiyan, the setup generated by breaking waves near the fringing-reef-protected town of Hernani, the Philippines, oscillated with the incidence of large and small wave groups, and steepened into a tsunami-like wave that caused extensive damage and casualties. Though fringing reefs usually protect coastal communities from moderate storms, they can exacerbate flooding during strong events with energetic waves. Typical for reef-type bathymetries, a very short wave-breaking zone over the steep reef face facilitates the freeing of infragravity-period fluctuations (surf beat) with little energy loss. Since coastal flood planning relies on phase-averaged wave modelling, infragravity surges are not being accounted for. This highlights the necessity for a policy change and the adoption of phase-resolving wave models for hazard assessment in regions with fringing reefs.

A new method of wave–turbulence decomposition is introduced, for which the only instrument required is one high-frequency pointwise velocity sensor. This is a spectral method that assumes equilibrium turbulence and no wave–turbulence interaction. Nonetheless, laboratory and field experiments show that the new method produces results in good agreement with the results of established wave–turbulence decomposition methods. Therefore, this spectral method proves useful when neither a synchronized wave gauge, nor a second velocimeter, is available. Furthermore, this study indicates that uncertainty in velocimeter probe orientation is responsible for most of the wave bias occurring in turbulent velocity data, so that an accurate measurement of this orientation makes wave–turbulence decomposition unnecessary.

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Field measurements and numerical simulations are used to assess the resons for different types of water-related structural damage observed in Tacloban and Eastern Samar. Coastal Tacloban saw heavy damage due to wind waves riding atop storm surge, while inland Tacloban experienced much lighter damage because wind waves were not present (though inundation by surge soiled structures). Eastern Samar experienced little wind-induced or pressure-induced setup, but breaking-wave-induced setup over the reef combined with wave runup and infragravity motions caused heavy damage along the coast.

In the aftermath of the Paris Agreements, many countries around the globe have pledged to reduce the amount of greenhouse gas emissions being released into the atmosphere. To do so, it is important that the amount of renewable energy in the electricity grid increases, though there are worries of the capacity of the grid to cope with intermittent energy sources. To assess the feasibility of a 100% renewable energy system in Japan, the authors conducted an hourly simulation of future electricity production based on wind, solar and tidal data in Japan. The system was shown to be stable, and the authors calculated the required capacity of electrical batteries that would be necessary to balance such a system.