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NASA's Guardian Tsunami Detection Tech Catches Wave in Real Time

157 points by geox

by rich_sasha

3 subcomments

This is unreal and beyond cool. Instead of measuring seismic tremors, it measures, indirectly, the displacement of the ocean surface. Far from the shore, tsunami waves are very long and very low - so they would appear as the whole surface of the ocean going up and down.
That motion pushes air upwards, resulting in a wave reaching high up through the atmosphere, eventually hitting (!) the ionosphere. I didn't even know acoustic waves would propagate through ionised gas!
Finally, this ionosphere disturbance affects GPS signal reception, and can be measured via ground receiver stations.
The upside of this is that it measures, indirectly, motion of the sea, i.e. actual tsunami activity, rather than monitoring directly the potential causes thereof.
It is crazy to me that it works though!

by mhb

1 subcomments

Near-real-time outputs from GUARDIAN must be interpreted by experts trained to identify the signs of tsunamis.
Hmm. Sort of giving stock market fundamental analysis.

by radarsat1

2 subcomments

The article mentions gravity waves, I thought these were not possible to detect except from massive events like black hole mergers. Am I getting concepts mixed up?

by chatmasta

2 subcomments

The article notes that the tech successfully notified researchers 20 minutes after the initial quake. What the article _doesn’t_ note is how often the researchers get these notifications.
I wonder what the false positive rate is like for this technology.

by zzzeek

0 subcomment

meanwhile current and former NASA employees are outside, today, protesting damaging budget and employment cuts by the federal government which will end or jeopardize many NASA programs:
https://www.space.com/space-exploration/nasa-employees-plan-...
this is the bigger story for the moment