Experimental Tech Measures Ripples In the Atmosphere

NASA’s GUARDIAN, or GNSS Upper Atmospheric Real-time Disaster Information and Alert Network, taps into signals from global navigation satellite systems such as GPS and others to detect distortions in the signals caused by pressure waves in the atmosphere generated by a tsunami.

The system demonstrated its viability after a magnitude 8.8 earthquake struck off the coast of the Kamchatka Peninsula in eastern Russia. The quake triggered a tsunami, forming a surge of water that in turn sends pressure waves propagating upward to the topmost layer of the atmosphere – the ionosphere – that distorts GNSS signals. The GUARDIAN system is able to distinguish those distortions from the background.

Scientists can observe the signal distortions and track the movement of the tsunami across the ocean, in this case, the Pacific Ocean. And although the actual waves caused little damage in Hawaii, the event clearly showed the ability of GUARDIAN to track their approach at least 30-40 minutes before their arrival.

Siddharth Krishnamoorthy, a scientist with NASA’s Jet Propulsion Lab in Pasadena, California, said, "Those extra minutes of knowing something is coming could make a real difference when it comes to warning communities in the path.”

In the Kamchatka tsunami, GUARDIAN provided valuable lead time for coastal communities in the tsunami’s path.

Christopher Moore, Director of the National Oceanic and Atmospheric Administration (NOAA) Center for Tsunami Research said, "NASA's GUARDIAN can help fill the gaps. It provides one more piece of information, one more valuable data point, that can help us determine, yes, we need to make the call to evacuate."

The GUARDIAN system is still being refined, and it requires expert interpretation, but it is one of the fastest tools available right now for monitoring tsunamis. It is able to sense sea surface motion from space and can detect the telltale atmospheric ripples within 10 minutes of receiving satellite data. This provides officials the ability to issue an alert and/or warning shortly after.

FMI:  www.jpl.nasa.gov/