...to volcanic alert levels BEFORE they go on volcanic island tours.
The recent tragedy in New Zealand is an unfortunate reminder of just how darn sneaky volcanoes can be, but it also shows the potential mistakes that
scientists can make. And those mistakes can cost lives. Scientists are in the unsavory position of having to be extremely conservative with their
warnings and alert levels at volcanoes, especially when those volcanoes are active tourist attractions.
People want to insist on visiting and living near active volcanoes, thinking "this will never happen to me!" Well scientists can only protect you so
far, and it is why they are always issuing disclaimers. They will be the first to tell you that eruptions can occur without warning. In this case
Geonet had raised the alert level to 2, but as it turned out, in hindsight they should have issued an alert level 3 at the very least, and severely
discouraged or even pushed to prevent visitors from going there for a while. And here is why:
I was able to get the raw seismic data from a station there, and it is interesting to see what occurred. In this first pic of a heliplot of the data,
things are just moving along as normal:
The spectrograph shows no abnormal activity just three hours or so before a special signal appears.
But then, some 16 hours before the eruption, a tremor signal is received:
Now see this is where the tough call has to be made, and it is unclear what happened at this point. But it proved not to be enough.
The Sun is reporting:
Just last month, authorities raised its Volcanic Alert Level to Level 2, as scientists observed increasing amounts of sulphur dioxide gas – a
key indicator of rising magma deep in its bowels.
Because just 16 hours or so later:
Eruption occurs in the middle of another tremor episode.
And people died.
Now imagine if this happened at Rainier. Or worse, at Yellowstone or Long Valley! We can only guess what our scientists might do in a similar
situation. But I have faith they won't take any chances in the case of very dangerous volcanoes such as the above mentioned. This incident at White
Island just underscores the need to not take any chances with people's lives. And yet, it is a tricky situation. Even with such tremor signals
present, volcanic eruptions are still rare. Often there is deformation, increased gas emissions, increased seismicity, and then.... nothing.
And this puts scientists in the difficult position of having to make the call. After it's all said and done, only people themselves can make the
choice. They DID have a choice to avoid that volcano for a while after the alert level went up. Unfortunately in this case, they gambled and paid with
Note there were no earthquakes in this case. Just the presence of volcanic tremor. That's all the warning that volcano gave in 20 hours or so. A scary
reminder indeed of the situation that may present itself to both scientists and the public in the future at a much more dangerous volcano.
on Mon Dec 9th 2019 by TrueAmerican because: (no reason given)