Last week the United Nations General Assembly approved the establishment of an "International Asteroid Warning Group." Researchers have identified more than 2,300 near-earth asteroids large enough to cause significant damage to the biosphere, but it is estimated that there are 100 times more that we have yet to identify. Clearly we needed a more organized and concerted global effort to reduce the possibility of a civilization-ending asteroid collision.
But what about supervolcanoes? Currently there is no public or private, national or international, effort to identify and prevent a supervolcanic eruption. And I would argue that supervolcanoes pose a greater threat to civilization than do asteroids.
Supervolcanic eruptions are classified as eruptions that eject 1,000-plus cubic kilometers of volcanic ash. Depending on where one erupted, a supervolcanic eruption has the potential to destroy an entire continent, as well as agriculture, transportation, and communication systems globally. According to our current knowledge, nine supervolcanoes have erupted within the last 6 million years. On scales of a human lifetime (or even our civilizations lifetime) that may not seem frequent. But consider that only one major asteroid collision has occurred in the past 65 million years. Based on those odds, we are far more likely to encounter a supervolcanic eruption than we are to encounter an asteroid collision.
In fact, modern humans have already encountered a supervolcanic eruption. The volcano underneath Lake Toba in modern-day Indonesia erupted 2,800 cubic kilometers of volcanic ash 74,000 years ago. Modern humans had only recently emerged from sub-Saharan Africa during this time period. Little is known about how we were affected, but there is evidence that our population dwindled and our migration rate into Asia was slowed.
Of course, human society was small-scale 74,000 years ago. Today a supervolcanic eruption would destabilize our entire system, and perhaps even lead to complete collapse. So what can we do?
Well, first we need to start thinking about phenomena that can occur on longer scales of time than we are accustomed to thinking about. On scales of geologic time, supervolcanoes occur with surprising regularity. As a result, we need to develop analogous program to the "International Asteroid Warning Group." In my opinion, here should be the group's basic plan of action:
- We must gain as much data and knowledge of past supervolcanic eruptions as possible.
- We must attempt to understand whether supervolcanic eruptions occur in any recognizable pattern on geologic time scales so that we can roughly estimate when we should expect the next major eruption.
- We must fund volcanology research in order to better understand the processes that occur decades (and even centuries) before a major eruption.
- And we must start to design technology and/or methods that could be used to prevent supervolcanic eruptions.
It isn't statistically probable that we will encounter a supervolcanic eruption within the next century (or even millennia). But it isn't statistically probable that an asteroid will hit us either, and that doesn't stop us from preparing for the worst. Human civilization is young and fragile. It took countless millions of years for our species to evolve, and it would only take one tragic natural disaster to knock it down. Therefore, funding for research that would allow us to prepare for the worst is imperative.
We are an intelligent species; hopefully we are also a prudent one.