Scientists: Earthquakes can be caused by global warming

I get really annoyed whenever there’s an earthquake and people say “it’s all because of global warming”. There is no doubt that climate change influences hurricanes and droughts, but earthquakes, tsunamis and volcanoes are all down to Earth’s natural processes.

Well at least that’s what I used to think, up until now. New research suggests that maybe I shouldn’t have been getting so annoyed with those people after all, because there may actually be a direct link between climate change and earthquakes. How on Earth is that possible, because what has the atmosphere - which causes global warming - got to do with the inner workings of our planet (which cause earthquakes)?

The science behind it is surprisingly simple. Because ice sheets become so huge, they ‘glue’ the land underneath them together. This prevents earthquakes happening because the power of the earthquake would not be enough to overpower the force of the ice which is holding the land together. 

So any stress building up between Earth’s tectonic plates carries on building up and building up, unable to be released. (In case you don’t know, tectonic plates are the massive lumps that make up the Earth’s surface, and can cause earthquakes by sliding past each other or colliding.) This is great as long as the ice is there, because it means there are very few earthquakes.

The problem comes when the ice melts: once the ice isn’t there to ‘glue’ the tectonic plates together, all the stress between the tectonic plates will suddenly be released. Depending on how fast the ice is melting, this stress could be released in a series of mini-quakes (if the ice is melting slowly) or a disastrous giant quake (if the ice melts really fast).

Isn’t this all just a big scare story - where’s the evidence? Well actually, the whole study was based on real evidence. Scientists found that a series of earthquakes near the Arctic around 10,000 years ago matched the time when the ice started melting, after the end of the last Ice Age. And they even managed to trace the quakes going gradually northward, as the ice retreated further north.

Every day the effects of human-induced global warming seem to get worse and worse. But it doesn’t have to be that way - small changes to our lives really can make a big difference.