An Operational Earthquake Forecasting Experiment for Israel: Preliminary Results

Operational Earthquake Forecasting (OEF) aims to deliver timely and reliable forecasts that
may help to mitigate seismic risk during earthquake sequences. In this paper, we build the
first OEF system for the State of Israel, and we evaluate its reliability. This first version of the
OEF system is composed of one forecasting model, which is based on a stochastic
clustering Epidemic Type Earthquake Sequence (ETES) model. For every day of the
forecasting time period, January 1, 2016 - November 15, 2020, the OEF-Israel system
produces a weekly forecast for target earthquakes with local magnitudes greater than 4.0
and 5.5 in the entire State of Israel. Specifically, it provides space-time-dependent seismic
maps of the weekly probabilities, obtained by using a fixed set of the model’s parameters,
which are estimated through the maximumlikelihood technique based on a learning period
of about 32 years (1983–2015). According to the guidance proposed by the Collaboratory
for the Study of Earthquake Predictability (CSEP), we also perform the N- and S-statistical
tests to verify the reliability of the forecasts. Results show that the OEF system forecasts a
number of events comparable to the observed one, and also captures quite well the spatial
distribution of the real catalog with the exception of two target events that occurred in low
seismicity regions.