Since 1975, the world has been warming at an alarming rate, with scientists stating that the global temperature has risen by roughly 0.15-0.20°C per decade. While this figure seems relatively low, global warming is undoubtably having an effect on the polar ice caps which continue to melt. Since 1979, the volume of ice in the Arctic, or North Pole, has shrunk by an astonishing 80 percent – but scientists have warned that this will not just cause sea levels to rise.
The melting ice caps also pose another major threat – and that is that they could cause major earthquakes.
A team of researchers from the Leibniz Universität in Hannover investigated a major fault zone running across Denmark over the course of 2.5 million years ago to 12,000 years ago – at the end of the last Ice Age.
The team found that as ice melted, it effected the sediment deep beneath the surface which essentially reactivated the fault line, according to the research led by Dr Christian Brandes.
The scientific journal Scientia read: “The 115-kilometre-long Osning Thrust underwent a series of faulting movements over a 140-million-year period ending about 60 million years ago.
“The team has shown that movements along this fault also occurred very recently. Modelling these structures has enabled Dr Brandes and his colleagues to demonstrate that the Osning Thrust was reactivated at the end of the last glaciation, around 12,000 years ago.
“This fault reactivation was accompanied by earthquakes, which the team identified from the soft-sediment deformation structures that developed in this area.
“Their findings also imply that an earthquake, which took place in this region during the autumn of 1612, might have been triggered due to stress changes in the Earth’s crust caused by a melting ice-sheet.”
The team believe the effect might be something known as “glacial rebounding”.
“If your mountain is a volcano you have another problem.
“Volcanoes are a pressurised system and if you remove pressure by ice melting and landslide, you have a problem.”
Professor David Rothery, a geoscientist at The Open University, said: “This new research nicely demonstrates that if you change the load on a volcanic mountain – for example by removing some ice – the likelihood of a mechanical collapse and possible ensuing eruption will be slightly increased.
“Eruptions are triggered by a complex array of factors.
“I suspect that many eruptions caused by glacial melting might happen eventually anyway, given enough time – but this research shows that warming could increase the chances of those eruptions happening sooner rather than later.”