8.4 Quake in California? Not so fast there, Twitterers...

If you have not read XKCD comics, you have been missing out on a great treat, especially if you are the scientific nerdy type of personality. On the heels of the Sierra El Mayor earthquake in Baja California, the comic above made the rounds, revealing a great truth: we are a wired, interconnected society (surprise!). Of course, there are the disadvantages as well.

So, to explain Tuesday's brief post: the XKCD comic above came true in a fashion...except there was no earthquake. I was checking my e-mails during a short break in my night class, and I had several people asking if the tweets they had received from friends were true, was the state of California declaring that an 8.4 magnitude quake would be hitting within the next 48 hours? Then I saw a few phones open up in class, and someone asked me directly about the Tweet on their phone. Clearly a rumor was spreading with the speed of electromagnetic energy and texting fingers. A hoax? An idiot crying 'fire' in a theatre? Undoubtedly. I posted my brief message explaining why the Tweet wasn't true, and had more than 2,000 hits in the space of 90 minutes. By the midnight, the 20th ranking query on Google was '8.4 magnitude earthquake in California'.

A lot of damage is done when rumors like this spread. No one can predict earthquakes, and a false prediction like this (or from 'psychics') can unnecessarily frighten people, and lead to a situation that will be perceived as crying 'Wolf'. People will stop paying attention to real warnings by qualified seismologists and vulcanologists.

We cannot predict earthquakes in such a way as to know the day, the week, or the month. We can use the history and prehistoric behaviour of fault zones to determine the possibility of a large quake within a time frame of decades. If you want a scientifically grounded prediction about earthquakes in California, check out the diagram below, from the Uniform California Earthquake Rupture Forecast (UCERF). The message to take away? Ignore the tweets, and pay attention to your personal emergency preparations. Quakes will happen.