All the dead birds and fish and things distracted me from an interesting article I read on Wired Science the other day about the potential for hurricanes to trigger earthquakes. It is a pretty good read so you should definitely go check it out. But I just wanted to talk about it a bit here. Now, keep in mind I am neither a climatologist or a geologist, so I won’t have as much scientific input on this matter, so anything I am saying here is based on my limited understanding of the material (in case you couldn’t tell you can read my other earthquake post or my hurricane posts here). Either way, I wanted to share it with you, but again, I encourage you to go read the original piece.
The author, Brian Romans, aka Classic Detritus, introduces a topic put forth by researchers from the University of Miami (led by Shimon Wdowinski) – the idea is that a series of powerful tropical storms in Haiti in 2008 eroded and shifted enough sediment on a deforested landscape that it may have stressed the fault line and triggered the massively devastating 2010 earthquake. When sediment is eroded, it needs to be deposited somewhere, and the researchers use models to show where the sediment was deposited and what kinds of stress impacts those shifting sediments were having on the fault. The researchers concluded that this mass of shifting sediment acted as a trigger for the earthquake. Romans, in the article, makes clear that the TRIGGER is not the same thing as the CAUSE. Earthquakes occur when boundaries build up stress, and then that stress is released along a fault. The researchers at UofM aren’t saying that hurricanes caused the earthquake, rather, that the shifting mass of sediment over an already stressed fault line due to excessive rainfall from tropical storms may have triggered the earthquake.
According the Romans, this isn’t even an entirely novel concept, as it has been proposed in peer-reviewed literature before. But Romans does caution about causation. In many fields of science, causation is often difficult to discern. Just because events or data are related doesn’t mean one causes the other. In fact, a common mantra is that correlation does not equal causation. For example, take the Church of the Flying Spaghetti Monster’s stance on global warming. Their argument is that as pirates (I think the more romantic version of swashbucklers, not the current AK47 wielding speed boat Indian Ocean pirates of modern times) have declined in numbers, average global temperature has increased. (Wow, is this my first ever Chronicles mention of the Flying Spaghetti Monster?)
Anyway, I digressed slightly. It is an interesting concept, and one that I had not even given a thought to before. Is it possible that system processes on the Earth’s surface can affect things that go on within the Earth’s crust? Interesting questions.