Man-made climate change, humanity’s most recognizable fingerprint on the natural world, is affecting everything. Increasing global temperatures may one day set off a greenhouse gas time bomb in the Arctic, just as it will cause sea levels to rise and swallow up low-lying coastal cities. Now, it appears that it’s also causing the entire Earth to wobble differently on its axis.
As a new study in the journal Science Advances reveals, the severe melting of massive ice sheets and the redistribution of water across the world is forcing the geographic North Pole to migrate eastwards towards continental Europe. It’s been doing this at an annual rate of about 10 centimeters (4 inches) since 2000, and it appears that human actions are, once again, to blame.
“What we have shown is that melting ice and a pattern of continental water storage are combining to cause a dramatic shift in the direction of the pole,” study co-author Surendra Adhikari, an Earth scientist at NASA's Jet Propulsion Laboratory (JPL) in California, told National Geographic.
Everything in space spins on an axis, from galaxies to asteroids. This axis can move, however, if the object in question is gravitationally influenced by something else, or if the distribution of its mass changes. Our neighboring Red Planet experienced a severe case of the latter 3.5 billion years ago when a vast volcanic eruption caused it to tip over an incredible 20 degrees.
The melting of land ice and the removal of surface water due to rising temperatures and agricultural activity has caused the Earth to wobble differently. NASA/JPL-Caltech
Earth is now experiencing its own axial alteration, in that it has been drifting at a significant pace since the turn of the millennium. At the same time, scientists have acknowledged that the current rate of increase in atmospheric carbon is the largest in the last 56 million years, which is causing a huge redistribution of mass as swaths of land ice melts. A pair of researchers from JPL became convinced that the two phenomena were linked, and they decided to use computer modelling simulations to see if their hunch was correct.
The Greenland Ice Sheet alone has shed over 3.5 billion tonnes (3.9 billion tons) since 2003, and all of this is collapsing and melting into the world’s oceans. This alone represents a massive shift in surface mass, but things don’t end here.
Every year, the West Antarctic Ice Sheet loses around 124 billion tonnes (136 billion tons) of ice, while the Eastern equivalent gains 74 billion tonnes (82 billion tons). The overall melting of the Antarctic ice will raise sea levels by 15 meters (49 feet) by 2500.
In addition, spiking global temperatures are causing massive water reservoirs to dry out, particularly near the equator. When all this is taken into account, the models show that this would cause Earth’s rotational axis to tilt at precisely the observed rate. To put it another way, the North Pole has moved eastwards by around 1.6 meters (5.2 feet) since 2000, and it will continue to do so.
This shift is, in itself, nothing to worry about; it won’t cause the planet to spin wildly out of control and hurtle into the Sun. Nevertheless, it is a startling reminder that man-made climate change is affecting almost everything – and it’s really something we should act on before it causes some serious harm.