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ElarmS takes the form of a suite of algorithms designed to (1) rapidly detect the initiation of an earthquake, (2) determine the size (magnitude) and location of the event, (3) predict the peak ground motion expected in the region around the event, and (4) issue a warning to people in locations that may expect significant ground motion. The algorithms use data from regional broadband seismic networks.

ElarmS is currently being tested by the CISN as part of the realtime seismic system in California. This pre-prototype test will allow assessment of the likely timeliness and accuracy of warnings if early warning is implemented for general use in California. ElarmS has also been tested offline using data from Japan, Taiwan, Italy, Alaska, the Pacific Northwest and California.

For more information please vist the ElarmS research page.

Onsite Algorithm
Probability of greater than or less than 0, 5,10, 20, or 30 seconds of warning for San Francisco for all WG02 earthquake scenarios.