Predicting and Forecasting Earthquakes
Predicting Earthquakes
humans (including scientists) can’t predict earthquakes
no such thing as “earthquake symptoms”
risk assessment is better
Prediction vs Forecasting
prediction: when will the next megathrust earthquake of >M8 happen in the pacific northwest?
forecast: what is the likelihood that a megathrust earthquake of >M8 will happen in the pacific northwest in the next 100 years?
Forecasting Earthquakes
use evidence of past earthquakes
historical earthquakes
geologic record
to find frequency of past earthquakes (return period)
useful for long term, imprecise prediction (or forecasting)
leads up to preparedness and good construction practices
Earthquake Warning Systems - Japan
alarm goes out when P - Waves are detected by seismometers near the epicenter
linked to cellular networks, TV, and radio
warning time = difference between P and S - wave arrival time
seconds to minutes
Predicting Earthquakes
humans (including scientists) can’t predict earthquakes
no such thing as “earthquake symptoms”
risk assessment is better
Prediction vs Forecasting
prediction: when will the next megathrust earthquake of >M8 happen in the pacific northwest?
forecast: what is the likelihood that a megathrust earthquake of >M8 will happen in the pacific northwest in the next 100 years?
Forecasting Earthquakes
use evidence of past earthquakes
historical earthquakes
geologic record
to find frequency of past earthquakes (return period)
useful for long term, imprecise prediction (or forecasting)
leads up to preparedness and good construction practices
Earthquake Warning Systems - Japan
alarm goes out when P - Waves are detected by seismometers near the epicenter
linked to cellular networks, TV, and radio
warning time = difference between P and S - wave arrival time
seconds to minutes