Yeah, and volcanoes are caused by global warming too. All 300 billion years of ‘em.
On a macro scale, I believe they are. I think, increases in the earth's temperature (which, occur naturally) probably trigger increases in plate movement, and thus... Earthquakes and volcanoes..
I think, volcanoes are a PART of the earth's temperature regulating system.
Just a theory... I'd love to see some data that attempted to correlate temperature with seismic activity.