The Yellowstone caldera is a supervolcano located in the US that last erupted 70,000 years ago. It has been labelled a supervolcano due to its potential to inflict devastation on a global level. There has not been an eruption of this nature in more than 630,000 years but scientists still believe it poses a threat.
Jacob Lowenstein, a leading scientist in charge of monitoring Yellowstone, revealed during a lecture at Menlo Park, California, how the USGS recorded an uprise in the ground over a seven-year period.
He said in 2014: “We have a technique that’s called InSAR – it’s another satellite-based technique like GPS.
“And it produced this particular image and it’s called an interferogram.
“inSAR is a radar technique – you have radar up in space and it’s taking an image of the land surface below – scanning the surface.
“You take an image and compare it – in this case 1996 to 2003 – and you can look at how the ground surface changed in elevation relative to that satellite.”
Dr Lowenstein then showed a map, where a number of rings appeared to get closer near the caldera.
He added: “What you get here is like a contour map – the yellow ring represents places that moved up a similar amount towards the satellite.
“But when the rings are really close together, that means there was a lot of movement.
“Here, we can see from 1996 to 2003, there was about 12cm of uplift in that period over a five mile radius.
“That is a large volume increase – but it dies off when you get to the outer areas.”
“This gives us an understanding of what is really happening, where the ground is moving and where it is coming up.”
Dr Lowenstein previously revealed why it is imperative to keep an eye on Yellowstone.
He said during the same lecture: “Yellowstone has a lot going on in it, it is a very active place.
“We have a volcano observatory there partly because we feel we need to keep a close eye on it because it does have this big hazard that’s a possibility there.
“There is no place on Earth that’s quite like Yellowstone, it has a big magma system and there are constantly things happening.”
Dr Lowenstein went on to reveal why monitoring such a unique volcano can help them to understand other threats across the globe.
He added: “We feel it is important that we as scientists know what is going on there and can present that data and can publish it for our colleagues all around the world.
“Because what we learn at Yellowstone really teaches a lot about volcanoes everywhere.
“A lot of volcanoes don’t do anything – they sit there having no activity at all until about two weeks before they erupt.
“At Yellowstone, we’re constantly seeing activity even though it hasn’t erupted for 70,000 years.”