Pasadena, California – A recent study published on Friday, April 8, in Science Advances, by researchers at NASA’s Jet Propulsion Laboratory (JPL), has found that global warming is changing the way the Earth moves, finding that water mass directly affects the inclination of the Earth, more specifically its spin axis.
The discovery was made using satellite data observations from the NASA/German Aerospace Center Gravity Recovery and Climate Experiment (GRACE) satellites, of how water moves around our planet, and it shows that droughts and the overuse of aquifers in Eurasia have caused a massive eastward drift of our axis over the past 16 years.
The movement of the Earth, called polar motion, for almost the entire 20th century, was inclined towards Canada, but in the current century, it has changed and now it’s moving towards England.
In previous studies, it was found that the melting ice sheets, due to high temperatures in Greenland and Antarctica, along with the change in global hydrology, were changing the distribution of weight on Earth, and contributing to the shift in Earth’s axis. It was reported that Greenland is losing an average of over 287 billion tons of ice a year, and Antarctica is currently losing 134 billion tons of ice a year. As more ice melts, the ocean water levels and volume will keep increasing.
But the melting ice sheets do not create the amount of energy necessary to pull the spin axis as it has shifted.
The researchers said that, due to the huge amounts of ice melted, since around the year 2000, Earth’s spin axis abruptly turned toward the east and is now drifting almost twice as fast as before, at a rate of almost 7 inches (17 centimeters) a year. But they also add that the combined effect of West Antarctica pulling and East Antarctica pushing, along with Greenland pulling from the north, due to ice mass loss in these areas, is still not enough to explain the speedup and the new direction of the Earth’s spin. Something east of Greenland has to be exerting an additional pull.
They found that, in Eurasia, there is a deficit of water, more specifically in the Indian subcontinent and the Caspian Sea area. They also added that these regions are losing water mass because of aquifers are running out of this liquid due to drought.
Even though the amount of water lost in Eurasia was not much, the researchers say that the spin axis is very sensitive to changes occurring around 45 degrees latitude, both in the north and the south.
Surendra Adhikari says that the Earth “is no longer moving toward Hudson Bay, but instead toward the British Isles. That’s a massive swing.”
Research has also shown that every six to 14 years the spin axis wobbles about 20 to 60 inches (0.5 to 1.5 meters), either east or west of its general direction of drift.
Some say that the shift itself will not cause any damage, but the fact that global warming is now having this sort of effect on the Earth is very relevant.
Source: Sci-tech Today