After people living in Southern California got over the shock of experiencing a magnitude-5.1 earthquake and a tropical storm occurring at the same time, many asked the question: Are the two natural disasters related?
Dr. Lucy Jones, a seismologist and author of "The Big Ones," said that although there is not a relationship between plate activity and weather above ground, a significant amount of rain water could theoretically cause seismic disruptions.
"The one way that it could (is) the pressure in the water in the ground does affect faults," Jones said. "If you go and build a great big reservoir and significantly increase the pore pressure, it's called, the pressure in the fluids in the ground, you could set off earthquakes. That's a well known fact."
But can the rain change the pressure underground?
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"You'd have to have a pretty large change in the water table to see it happening, and we've looked for this pattern because there is this sort of theoretical marginal potential for it happening," Jones said. "But nobody's been able to demonstrate that it happens more often.
"We need to remember that the most human response that we have is that we want to find a pattern," she said. "Because if we can find a pattern, then we can say 'I'm safer at times when that pattern isn't there.' And so, we have a pretty strong psychological drive to look for those patterns and try to find them... And so far, nobody's been able to really confirm that pattern."
There is no evidence linking the earthquake on Sunday near Ojai, California, to Tropical Storm Hilary. In fact, Jones said there was a similarly sized earthquake in the exact same location in 1932 and another 5.1-magnitude earthquake west Ojai in 1941. Also, several aftershocks from the 1994 Northridge earthquake were felt in the area as well.
