The most important information that is immediately needed for earthquake disasters is the location, depth, and magnitude of the earthquake. The most common method of establishing an earthquake's magnitude is using seismic sensors on the ground that measure the shaking of the earth's crust. Authorities and first responders need better data to accurately and quickly assess the risk associated with the earthquake.

NASA's Jet Propulsion Laboratory and Scripps Institution of Oceanography have upgraded scientific GPS stations with sensors that monitor for earthquakes while collecting GPS, pressure, temperature, and seismic data in real-time across southern California. The weather data is used to account for the water vapor that the GPS signal travels through, thereby enhancing the accuracy of the GPS data.

The stations then send the information to Scripps via the internet and radio waves—which travel faster than shock waves—where scientists use the GPS data to measure exactly where and by how much the ground moved during an earthquake. The GPS data are then inputted into computer models to estimate the earthquake's location, magnitude, depth, and tsunami potential. This can all happen within minutes, enabling rapid and more accurate earthquake data than ever before.

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