The problem of estimating an earthquake’s energy
One of many trickiest elements of an EEW system is estimating the magnitude of an earthquake in real-time. The magnitude tells us how huge the earthquake is, which in flip determines how far the shaking will journey and who must be alerted. Getting this proper is essential — underestimate, and also you may not warn individuals in peril; overestimate, and also you threat sending out false alarms that erode public belief.
The problem lies within the trade-off between velocity and accuracy. The primary few seconds of an earthquake present restricted information, however each second you wait to problem an alert is a second much less of warning for these within the path of the shaking.
Over the past three years, we have repeatedly improved our magnitude estimation. The median absolute error of our first magnitude estimate has dropped from 0.50 to only 0.25. After we evaluate our system to established, conventional seismic networks, our accuracy is comparable, and in some circumstances, even higher.