Natural Hazards

Let the ash fall, but get ready for its consequences

Francisco Cáceres May 27, 2019

Figure 1. May 18th, 1980 eruption of Mt St Helens eruption. Images from UGSG

The past 18th May marked 39 years since one of the most emblematic volcanic eruptions in historic times: the 1980 Mt St Helens explosive eruption. With a death toll of 57 victims, it is the deadliest volcanic event in U.S. history. If that wasn’t enough, it also destroyed hundreds of houses and roads. When we think about explosive volcanic eruptions what commonly comes in our minds about the possi ...[Read More]

Our audience on stage: new NhET blog column

Giulia Roder May 14, 2019

Image source Pexels

The diffusion of social media such as Facebook, Twitter, etc. in addition to traditional blogging led to a diversification in the impact of science communication. However, as Eryn Brown and Chris Woolston wrote in Nature last January, blogs continue to be effective platforms for disseminating research into the world and increase the discovery of science. This is the reason why we believe our natur ...[Read More]

Alpine rock instability events and mountain permafrost

Stefano Alberti and Margherita Cecilia Spreafico April 29, 2019

Figure 1 – Deposits on the Porchabella Glacier where ice was found on top of a boulder. Ice was also present in the detachment zone of the rock slope failure, as observable in the upper left corner zoomed photo (from Phillips et al., 2017[13])

Rockfalls, rock slides and rock avalanches in high mountains The terms rockfall, rock avalanche and rockslide are often used interchangeably. Different authors have proposed definitions based on volume thresholds, but the establishment of fixed boundaries can be tricky. Rockfall can be defined as the detachment of a mass of rock from a steep rock-wall, along discontinuities and/or through rock bri ...[Read More]

InSAR Norway: the big eye on Norwegian unstable rock slopes

Gabriele Amato April 15, 2019

Fig.1. Screenshot from insar.ngu.no that shows, for each coloured point, its mean movement (in mm/y) and the time series of its displacement.

Marie Keiding is a researcher in the Geohazard and Earth Observation team at the Geological Survey of Norway. Together with her colleague, John Dehls, who is leading the project, she works to develop and operate the new mapping service called InSAR Norway. Before we start, let’s briefly describe what is InSAR. First, the Synthetic Aperture Radar (SAR) is a day and night operational imaging system ...[Read More]