The location of the North Pole is determined by the Earth’s axis of rotation. This axis ‘wobbles’ for a number of reasons, including the fact that the Earth isn’t rigid and factors related to its annual movement around the sun. Now, a team led by Jianli Chen of the University of Texas at Austin has shown that melting of the ice sheets is also inducing a shift in the axis and, hence, the pole’s position.

Since observations began in 1899, the North Pole has been drifting southwards at a rate of ten centimetres per year as the Earth’s crust slowly rebounds after the end of the last ice age, changing the distribution of mass in the planet. But according to the new study, in 2005, this southward drift abruptly changed and the pole began moving eastwards, shifting by about 1.2 metres since then.

Using data from NASA’s GRACE satellite, which measures changes in the Earth’s gravity field, the scientists were able to calculate the way in which mass on the surface has been redistributed as ice has melted from ice sheets and glaciers. The results correlated perfectly with the way in which the pole’s position has changed.

‘Ice melting and sea level change can explain 90 per cent of the [eastward shift],’ Chen told New Scientist. ‘The driving force for the sudden change is climate change.’

This story was published in the February 2014 edition of Geographical Magazine