In 1993, Stanley Williams survived a close-encounter with a volcano. A volcanologist, he was standing on the rim of Colombia's Galeras volcano when it erupted with little warning. Six of his scientific colleagues and three tourists were killed. Williams fled down the mountain's slope — until flying rocks and boulders broke both his legs. With a fractured skull, he managed to stay conscious enough to huddle behind some other large boulders and dodge flying debris until the eruption ended and his grad students rescued him.
Williams and the other scientists were there to study Galeras, and hopefully get a better idea of what signals predicted the onset of eruptions.
This is something we still don't understand well.
While volcanologists have identified some signals — like distinctive patterns of small earthquakes — that increase the likelihood of an oncoming eruption, those signals aren't foolproof predictions. There are still volcanoes like Galeras that give no warning. And volcanoes like Mt. St. Helens. In 2004, that volcano gave signals that it would erupt. And it did. Sort of. The Seattle Times described it as "two small burps and a lava flow". Basically, the signals don't always precede an eruption, and even when they do happen it doesn't tell you much about how big any ensuing eruption will be.
And that presents an interesting question, writes Erik Klemetti at Wired's Eruptions blog. How close to volcanoes should tourists really be? That's a question with real-world applications. This year, New Zealand's White Island volcano has been ... rather grumbly. Even as tourist boats continued to ferry people over for a view of the crater.
There has always been a fragile relationship between volcanoes and tourism. Volcanic features are some of the most fascinating in the world – just look at the millions of people who visit Yellowstone or Crater Lake National Parks for but two examples of hundreds of volcanic tourist attractions around the world (and that doesn’t even consider all the extinct volcanoes or volcanic deposits that can create amazing landscapes as well). However, with the splendor of volcanic features comes the danger that you, as a tourist, are visiting an active volcano. Sometimes, that danger is low, where either the volcano has been dormant for thousands of years, but the signs of magma beneath are still visible. However, the danger can appear to be low in some places but in reality, you are literally putting your lives in the hands of tour operators when you make the visit.
Read Stanley Williams' account of surviving the Galeras volcano
Photo by Michael Rogers, via GFDL and CC