Satellites can help detect when a volcano is expanding


Just like us While most symptoms can often spot the onset of an illness, there are signs of volcanic activity that could indicate an increased likelihood of an eruption. These observations may involve surface changes and small earthquake detection due to the magnetic field within them. Volcanoes, Or measures changes in gases emitted from vents. These symptoms are used to trigger alerts and evacuations and they save lives. But these are not always perfect.

Mount Ontake in Japan Originated in 2014 Killing more than 60 people, for example, without warning. So additional methods for identifying volcanic activity are always welcome, especially if they involve subtle signs that can be ignored. A new research study from the Jet Propulsion Laboratory Group led Tarsilo Girona Highlights the possibilities currently available Satellite Data can provide a whole new way Explosion warning.

Heat is obviously a relevant parameter for volcanic activity but it can be quite variable in individual spots where you can place the thermometer. If we could measure all the heat coming from the volcano instead, it would make a lot of sense, since most of the energy in the volcano is released as heat.

To try it, the team turned up Heat radiation data From NASA’s Terra and Aqua satellites. Combined, these two provide double-daily passes with global coverage, and each measurement combines 1km by 1km of pixels. There have been five significant volcanic eruptions since 2002 (when these satellites came online) and they are not located on an island that is not small enough to scatter enough pixels for good signals. Do Fogo.

Ontek’s Wonder 2014 has seen a trend of rising temperatures in the two to four years before each eruption, including the eruption. Temperatures only increased by 1 degree Celsius or less to lead up to each event, but these were statistically significant trends and not just noise. The top temperature of each record was associated with a volcano.

Researchers say this could represent a combination of two processes. First, the magma progresses near the surface and releases gases – which can stimulate hydrothermal circulation, carrying heat from below to warm the surface. Second, if it pushes more moisture into the soil layer, the ground can emit thermal radiation more efficiently and therefore appear “brighter” on satellites. Either way, these subtle changes seem to be easily identifiable in satellite data.

This provides a more meaningful metric to fill in the complete picture of volcanic activity. It can also make it easier to study the total heat budget of a volcano – the balance of energy coming from below and when and where all is revealed. Combined with other observation tools, satellite information can be easily used to increase alert level confidence, leaving short-term events in the long run. And the more symptoms we notice, the less likely we are Miss important warning signs.

This story originally appeared Ars Technica.


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