Physical experiments of waves generated by submerged steam eruptions with applications to volcanic tsunamis.

The tsunamigenic potential of underwater volcanic eruptions is not well understood, even though eruption-generated tsunamis can be devastating. To address how erupted steam bursts from underwater volcanoes generate tsunamis, we present the experiments, using pressurized steam injected vertically into a water tank. Results over various eruption conditions identify three eruption regimes, namely, shallow-, intermediate-, and deep-water eruptions, according to the combined effects of water depths, source strengths, and source durations.

Volcaniclastic density currents explain widespread and diverse seafloor impacts of the 2022 Hunga Volcano eruption.

The impacts of large terrestrial volcanic eruptions are apparent from satellite monitoring and direct observations. However, more than three quarters of all volcanic outputs worldwide lie submerged beneath the ocean, and the risks they pose to people, infrastructure, and benthic ecosystems remain poorly understood due to inaccessibility and a lack of detailed observations before and after eruptions. Here, comparing data acquired between 2015 - 2017 and 3 months after the January 2022 eruption of Hunga Volcano, we document the far-reaching and diverse impacts of one of the most explosive volcanic eruptions ever recorded.

The need to reconfigure consistency and variability to best manage changing flood risks in Aotearoa-New Zealand.

Flooding is Aotearoa-New Zealand's most frequent natural hazard, and there is high confidence that climate change is making extreme rainfall events more frequent and intense. Additionally, there are significant development pressures which could both increase the number of people and assets at risk and the flood hazard. To date, there is no publicly available consistent approach to accurately determine flood risk on a national scale, nor for how this may be changing; although there is a growing legislative requirement to provide quality information over multiple spatial scales.