Warming Earth will wobble, spin faster

As climate change melts ice sheets in the Arctic, it will also cause the Earth’s axis to tilt and make the planet spin faster, according to new research.

Both effects are also likely to accelerate as climate change speeds up.

Writing in the journal Geophysical Research Letters, researchers Felix Landerer, J. J. Jungclaus, and J. Marotkze describe how less ice and more water will affect the distribution of mass around the planet, which alters the tilt of the Earth’s axis, which is currently about 23.5 degrees from the vertical.

While the axis is already on the move — thanks in part to land masses still rebounding from the weight of massive ice sheets during the last ice age — the increased flow of fresh water from ice-covered regions like Greenland are adding to the action. The new study estimates that climate-driven effect is shifting the axis by about 2.6 centimetres per year, a rate that’s likely to accelerate.

The expansion of warming oceans will also contribute to the effect as more water covers now-shallow areas, the researchers find. That impact will add another 1.5 centimetres of motion per year to the Earth’s axis.

Also, in a warmer world, more of the planet’s mass will shift toward the poles, causing the Earth to spin just a bit faster than it is today.