The Sierra Beyond Yosemite: Politics and Geology Square Off in a Town with a Big Problem

Twin Lakes, above the town of Mammoth Lakes on the edge of the Long Valley Caldera

So what happened in Mammoth Lakes?

In the last post we talked about the titanic explosion at the Long Valley Caldera 760,000 years and tried to comprehend the scale of an event where 150 cubic miles of ash was blown into the atmosphere, covering much of the country. We then fast-forwarded to the near-present day of Mammoth Lakes in the 1980s. When we left the story, geologists were trying to decide what to do at the ski resort town in the face of astounding earthquake swarms, ground level changes, and increased geothermal activity.

It could probably be called a (tragi)comedy of errors. The USGS volcanologists carefully prepared a report to accompany a NOTICE OF POTENTIAL VOLCANIC HAZARD, the lowest level warning in their guidelines. A reporter from the Los Angeles Times figured out what was going on, and published a story about the potential volcanic activity the day before the USGS released their report. The geologists got scooped, in other words, and the story became a runaway train in the national media.. The government and emergency services personnel who were supposed to get the report and develop a response plan were blindsided by reporters asking them how it felt to be living in a doomed town.

The carefully worded statement from the USGS noted that "available evidence is insufficient to suggest that a hazardous event is imminent", but it was their description of the hazards that caught the attention of reporters and news hosts: rocks falling out of the sky miles from the eruptive vents, hot ash flows melting thick snowpacks and producing dangerous mudflows, and dangerous gases suffocating people. The very manna of the most desired headline: if it bleeds, it leads.

Hot Creek, a geothermal site in the Long Valley Caldera

By some accounts, the damage to the economy of Mammoth Lakes from the media circus may have been worse than an actual volcanic eruption (though no one died). Tourists stayed away in droves, businesses went belly up, and condo projects were abandoned. The business leaders of the town were livid at the geologists for stirring things up and scaring people (although by my reading, their notices were very conservative and carefully worded). They demanded that the geologists stop their campaign of terror/error, accusing them of bad science or something darker. There were even bomb threats (I had forgotten that detail; see the reference at the end of this post).

Warning sign at Horseshoe Lake, one of the carbon dioxide tree-kill sites on Mammoth Mountain.

The geologists could only respond in disbelief. I feel like I would have said  something along the lines of "You are sitting on top of an active body of magma that is a few thousand feet from the surface! It would be irresponsible to keep such a thing secret". The geologists stuck to their guns, and the threat level remained at level one, the lowest level of concern, but concern nonetheless.

The business owners and local politicians went up the chain of command. They appealed to the head of the USGS, and his boss, the Secretary of the Interior, a man named James Watt. They may have communicated with then-president Reagan. As far as I can tell, there was intense political pressure from above, and eventually the director of the USGS unilaterally scrapped the warning system. Poof! It was gone. No discussion. It its place would be an informal warning system of quiet communications between geologists and civic leaders.

If this were a Hollywood movie, what happens next would be preordained. Everyone would come back. The skiers would be happily sliding down the slopes, businesses would be taking in money hand over fist, and suddenly out of nowhere there would be a resounding explosion and all hell would break loose as the caldera gives way to a catastrophic eruption that kills the "evil" business leaders because they had been greedy, and a gritty, yet handsome geologist would lead a beautiful woman and her plucky children to safety. Heck, I could see casting someone like, oh, say, Pierce Brosnan as the geologist and Linda Hamilton as the lady. Maybe call it "Dante's Peak" and move the setting to Idaho for some reason.

Yeah, I'd say that casting choice for the geologist was about right. Either one of them....

But that isn't what happened, of course. The molten magma was almost certainly there, but it cooled and solidified instead of continuing to the surface. The earthquake swarms ebbed, but other swarms have taken place over the years, though most have been tectonic in origin (related to faulting rather than magma). Gases from the magma chamber, especially carbon dioxide, have continued to seep from the ground, killing trees and other vegetation in several areas, including Horseshoe Lake (below). The gases actually killed three people a few years ago.  After some years, the USGS established a volcano observatory that monitors Long Valley, and came up with a new warning system, one with four stages, and specific actions to be taken with each. It's based on colors, just like the terrorism warning system! The town's economy slowly recovered. They started building condos again.

Tree kill area at Horseshoe Lake. Carbon dioxide in the soil suffocates the roots and microorganisms necessary for the tree's survival

Some of the political leaders took a bit of action. One of the main concerns was that an eruption would have destroyed the only paved road out of town. No evacuation would have been possible if the highway was blocked off. A few years after the brouhaha, a road appeared at the upper end of town called the Mammoth Lakes Scenic Route. I have to say that as a geologist that I didn't see a whole lot of scenery as I drove this nice paved highway, but I couldn't help but notice that it was exactly where I would have chosen to put an evacuation route (according to Dick Thompson in Volcano Cowboys, the county supervisors responsible were recalled from office for arranging this bit of road-building; it was like an admission that volcanism was actually possible).

Hot Creek, one of the centers of geothermal activity within the Long Valley Caldera.

In the end, one can only say mistakes were made. Some of those mistakes involved a sort of public relations tone deafness, like releasing a volcano warning on the eve of a holiday weekend, but other mistakes were more nefarious.

There were people willing to deny the possibility of a natural catastrophe in order to protect their profit margins. I see parallels in today's political (but not scientific) debates over global warming and climate change. The geologists had clear evidence of a volcanic threat and the civic response was to deny the evidence and to attack the reputation of the geologists who were trying to do the right thing. There was a threat to the economy of Mammoth Lakes, but the threat was from a geologic process, not those who discovered and analyzed the volcanic hazard. And threatening the lives of the geologists was criminal.

And the media. What to do about the media? Isn't it amazing how media outlets were willing to blow a story way out of proportion in order to gain ratings? Isn't it nice to know that they don't do that sort of thing anymore? And that the internet (which didn't exist as such in 1983) has turned out to be the very model of accurate and measured analysis of stories like this one, despite the possible instant dissemination of incorrect and potentially dangerous information? I'm so glad we live in an age of logic and reason and respect of scientific research.

Oh, I'm sorry. I briefly stepped into "Opposite-world". I'm back now. Science education and science literacy have never been more important in a world where the internet and media are so irresponsible with their analysis of geological hazards. Every time there is another major earthquake or volcanic eruption, I feel like throwing a shoe through the television screen or computer monitor as the talking heads begin babbling. Instead, I do what I can by throwing words out into the internet trying to offer up a more measured explanation of things. But the mostly ignorant talking heads always seem to win people's attention.

Just imagine the outcome if the geologists at Mammoth Lakes were effectively squelched, no warnings were ever given, and a volcanic eruption had actually occurred. Beyond the devastation, just imagine the scapegoating that would have happened in the aftermath. In Italy such a situation led to prison terms for half a dozen geologists who failed to predict a deadly earthquake (they have since been released).

We can do better than this. Especially those in the news business who are responsible in times of emergency for providing us with reasoned assessments, not sensationalist dribble. When the crisis is over they can go back to their manic headlines about the personal lives of the stars.

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Although aspects of this story of the events at Mammoth Lakes and the Long Valley Caldera are drawn from my memory, I reviewed and confirmed many of the details in the excellent book called "The Volcano Cowboys: the Rocky Evolution of a Dangerous Science" by Dick Thompson (St. Martin's Press, 2002). Check it out, it's a fascinating account of the lives and activities of volcanologists.