We explored the potential of a sedimentary sequence in Valle d'Aosta (Northern Italy) as a natural archive of hazards. Our results suggest that this sequence is regionally the most sensitive to earthquake shaking with the record of 8 earthquakes over the last ~270 years and that it well represents the regional and (multi-)decennial variability of Mediterranean summer–autumn floods. Hence, this sequence offers a great potential to extend chronicles of regional floods and earthquakes back in time.

We evaluate for the first time a new class of optical satellite images for measuring Earth surface displacements due to earthquakes – images from cubesats. The PlanetScope cubesats used in this study are 10 cm × 10 cm × 30 cm small and standardized satellites. Around 120 of these cubesats orbit around Earth and are about to provide daily 2–4 m resolution images of the entire land surface of the Earth.

Numerical simulations are performed to understand the effects of several factors on tsunami wave impact and run-up in the presence of submarine gentle slopes and coastal cliffs using an in-house code. The run-up on a toe-erosion cliff is smaller than that on a normal cliff. Two impact pressure peaks exist during the tsunami wave run-up and impact. One is the direct impact pressure when tsunami waves first hit the coastal cliff, and the other is caused by the backflow from the cliff run-up.

Impulse waves generated by landslides threaten the safety of wide waterways and people living at the shore; as such, impulse waves require further study. The research on impulse waves induced by landslides is entered into the fluid–solid full coupling model, which can describe the movement of the landslide and the following water wave accurately. This paper provides a numerical model of the fluid–solid full coupled model, which uses the Mih equation for continuous non-coherent granular flow.

On 15 February 2013 at 09:20 local time in the vicinity of the city of Chelyabinsk, Russia, a meteorite exploded and collapsed in the earth's atmosphere as a result of inhibition. Small fragments of the meteorite came down on the Chelyabinsk region. The results of the numerical modeling of the processes that began in the water after the meteorite entered Lake Chebarkul in the framework of the Navier–Stokes equations are presented in this paper.

One of the quickest means of tsunami evacuation is transfer to higher ground soon after strong and long ground shaking. Ground shaking itself is a good initiator of the evacuation from disastrous tsunami. Longer-period seismic waves are considered to be more correlated with the earthquake magnitude. We investigated the possibility of applying this to tsunami hazard alarm using single-site ground motion observation.

A huge tsunami in Southeast Asia in 2004 has stimulated a debate about the role played by coastal ecosystems in protecting coastal area. Previous approaches assumed that vegetation is stationary and neglected the plant motion with wave. This may lead to overestimation of the effectiveness of coastal vegetation on tsunami damping. We present a coupled wave–vegetation simulation and conclude that the tsunami wave height damping may be overestimated if vegetation motion with wave is neglected.

Volcanic mudflows, called lahars, can cause large amounts of damage to buildings. In this research we developed a method to estimate lahar-induced building damage based on the height, speed and amount of volcanic material in the lahar. This method was applied to a small region in Arequipa, Peru, where computer models were used to estimate the number of buildings affected by lahars. The research found that building location and the size of the flow are most important in determining damage.

On 27 February 2010, a devastating tsunami M_w 8.8 was generated off the coast of Chile, causing the death of more than 500 people. In Dichato (37° S), we analyzed new risk areas derived from the process of reconstruction, and we compared it with risk analysis prior to the event. Six years after the event, we determined that the new risk configuration is similar to what existed previously. The process of reconstruction has not been undertaken effectively to reduce the risk levels in the area.

The increasing number and severity of floods, driven by e.g. urbanization, subsidence and climate change, create a growing need for accurate and timely flood maps. At the same time social media is a source of much real-time data that is still largely untapped in flood disaster management. This study illustrates that inherently uncertain data from social media can be used to derive information about flooding.

We create multiple DEMs from photographs taken by helicopter and UAV and reveal the deposit volumes over the Langtang village, which was destroyed by avalanches induced by the Gorkha earthquake. Estimated snow depth in the source area is consistent with anomalously large snow depths observed at a neighboring glacier. Comparing with a long-term observational data, we conclude that this anomalous winter snow amplified the disaster induced by the 2015 Gorkha earthquake in Nepal.

We plot the dike costs divided by their length as a function of height and test four different regression models. Our analysis shows that a linear function without intercept is sufficient to model the costs, i.e. fixed costs and higher-order contributions are less significant. We employ log-normal distributions and calculate that the range between 3x and x/3 contains 95% of the data, where x represents the regression value. We compare estimates from Canada, the Netherlands, US, UK, and Vietnam.

The purpose of this research is to evaluate the predictive capability of simplified liquefaction models that can be applied across wide geographical areas for insurance and risk management purposes. Predictions from nine models are compared to observations from the Canterbury earthquake sequence and finds that models based on a previously proposed Liquefaction Potential Index perform the best, whilst the commonly used HAZUS methodology does not perform well.

This study describes a sensitivity analysis of the RAMMS debris-flow entrainment model, which is intended to help solve problems related to predicting the runout of debris flows. The results indicate that the entrainment model predicts plausible erosion volumes in comparison with field data. These eroded volumes are sensitive to the initial landslide volume, suggesting that this tool may be useful for both reconstruction of historical events and modeling of debris flow scenarios.