How accurate and reliable are reported perceptions of quakes?
Scientists rely on the public's reporting of ground shaking to characterize the intensity of ground motion produced by an earthquake. How accurate and reliable are those perceptions?
A new study by Italian researchers suggests that a person's activity at the time of the quake influences their perception of shaking more than their location. Whether a person is at rest or walking plays a greater role in their perception of ground motion than whether they were asleep on the first or sixth floor of a building. People in motion had the worst perception.
"People are like instruments, more or less sensitive," said Paola Sbarra, co-author and researcher at the Istituto Nazionale di Geofisica e Vulcanologia in Rome, Italy. "A great amount of data and proper statistical analysis allowed us to make a fine-tuning of different conditions for a better interpretation of earthquake effects," said Sbarra.
The paper, co-authored by colleagues Patrizia Tosi and Valerio de Rubeis, is published today in the March issue of the Seismological Research Letters (SRL).
Sbarra and colleagues sought to analyze two variables – how an observer's "situation" and "location" influenced their perception in order to improve the characterization of low macroseismic intensities felt near small earthquakes or far from larger ones. Contrary to their findings, the current European macroseismic scale, which is the basis for evaluating how strongly an earthquake is felt, considers location the stronger indicator for defining intensity.
The authors analyzed data submitted to "Hai-sentito-il-terremoto?," which is similar to the U.S. Geological Survey's "Did You Feel It?" website that analyzes information about earthquakes from people who have felt them. After an earthquake, individuals answer questions about what they felt during the quake, along with other questions regarding their location and activity.
Intensity measures the strength of shaking produced by the earthquake at a certain location. Intensity is determined from effects on people, human structures, and the natural environment.
The number of people who feel an earthquake is critical to determining intensity levels, and low intensity earthquakes generate fewer reports, making objective evaluation of shaking difficult.
The journal SRL is published by the Seismological Society of America, which is the leading research society devoted to the study of earthquakes.
Nan Broadbent | EurekAlert!
New Link Between Ocean Microbes and Atmosphere Uncovered
22.05.2015 | University of California, San Diego
Scientists tackle mystery of thunderstorms that strike at night
21.05.2015 | National Center for Atmospheric Research/University Corporation for Atmospheric Research
Physicists have developed an innovative method that could enable the efficient use of nanocomponents in electronic circuits. To achieve this, they have developed a layout in which a nanocomponent is connected to two electrical conductors, which uncouple the electrical signal in a highly efficient manner. The scientists at the Department of Physics and the Swiss Nanoscience Institute at the University of Basel have published their results in the scientific journal “Nature Communications” together with their colleagues from ETH Zurich.
Electronic components are becoming smaller and smaller. Components measuring just a few nanometers – the size of around ten atoms – are already being produced...
Development and implementation of an advanced automobile parking navigation platform for parking services
To fulfill the requirements of the industry, PolyU researchers developed the Advanced Automobile Parking Navigation Platform, which includes smart devices,...
The world's first electrical car and passenger ferry powered by batteries has entered service in Norway. The ferry only uses 150 kWh per route, which...
On Tuesday, 19 May 2015 the research icebreaker Polarstern will leave its home port in Bremerhaven, setting a course for the Arctic. Led by Dr Ilka Peeken from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) a team of 53 researchers from 11 countries will investigate the effects of climate change in the Arctic, from the surface ice floes down to the seafloor.
RV Polarstern will enter the sea-ice zone north of Spitsbergen. Covering two shallow regions on their way to deeper waters, the scientists on board will focus...
Nanoengineers at the University of California, San Diego developed a gel filled with toxin-absorbing nanosponges that could lead to an effective treatment for skin and wound infections caused by MRSA (methicillin-resistant Staphylococcus aureus), an antibiotic-resistant bacteria. This "nanosponge-hydrogel" minimized the growth of skin lesions on mice infected with MRSA - without the use of antibiotics. The researchers recently published their findings online in Advanced Materials.
To make the nanosponge-hydrogel, the team mixed nanosponges, which are nanoparticles that absorb dangerous toxins produced by MRSA, E. coli and other...
20.05.2015 | Event News
18.05.2015 | Event News
12.05.2015 | Event News
22.05.2015 | Materials Sciences
22.05.2015 | Information Technology
22.05.2015 | Materials Sciences