On a previous EarthDate we talked about GPS, the Global Positioning System, and recent improvements that allow mapping down to the millimeter—accurate enough to detect the creeping movement of Earth’s tectonic plates.

These advances have inspired scientists to use GPS in many new ways to better understand earthquakes and other Earth processes.

The signals from GPS are very long—many thousands of digits—making them too slow to track seismic activity.

But recently, scientists realized they could use a different, much shorter part of the GPS signal and combine that with faster refreshing of GPS receivers.

This has allowed GPS to monitor earthquakes very accurately over a very broad area, enough to see their impact on distant communities.

And hopefully with new developments, fast enough to warn them of an impending quake.

Using similar technology, scientists can now measure and track other disruptions on Earth’s surface, such as sinkholes, landslides, and tidal waves.

Volcanic ash can disrupt GPS signals, so scientists devised a way to use those disruptions to monitor ash plumes and warn airplanes.

Similarly, water vapor in the atmosphere can delay GPS signals. Meteorologists are now reading that delay to predict heavy rainfall and advise communities about flash floods before they arrive.

All very interesting examples of how improvements in technology allow for advances in science.