Shifts in Water Mass Across Globe Direct North Pole Toward British Isles
Entertainment| | By Jason Owen
According to NASA, “Although a desktop globe always spins smoothly around the axis running through its north and south poles, a real planet wobbles… These wobbles don’t affect our daily life, but they must be taken into account to get accurate results from GPS, Earth-observing satellites and observatories on the ground.” So what causes these wobbles? The distribution of warm and cold water around the planet. In a paper published on April 8 in Science Advances, Surendra Adhikari and Erik Ivins of NASA’s Jet Propulsion Laboratory, in Pasadena, California, “researched how the movement of water around the world contributes to Earth’s rotational wobbles. Earlier studies have pinpointed many connections between processes on Earth’s surface or interior and our planet’s wandering ways. For example, Earth’s mantle is still readjusting to the loss of ice on North America after the last ice age, and the reduced mass beneath that continent pulls the spin axis toward Canada at the rate of a few inches each year.” But as the scientists discovered, around the year 2000, Earth’s axis took an abrupt turn toward the east and is moving almost twice as fast as ever previously recorded, “a rate of almost seven inches (17 centimeters) per year.” The North Pole is now heading toward England. So why the abrupt change? There are two main reasons, both stemming from events tied to global warming. First scientists looked at the loss of mass from Greenland and Antartica’s rapidly melting ice sheet. The JPL scientists “assessed this idea using observations from the NASA/German Aerospace Center Gravity Recovery and Climate Experiment (GRACE) satellites, which provide a monthly record of changes in mass around Earth.” Adhikari and Ivins’ calculations found that the changes in just Greenland and Antartica were “still not enough to explain the speedup and new direction.” However, taking these drastic polar changes accompanied by a “deficit of water in Eurasia: the Indian subcontinent and the Caspian Sea area,” provides the “bulk of the answer.” According to NASA, the “region has lost water mass due to depletion of aquifers and drought” and because of its proximity around 45 degrees latitude, the “spin axis is very sensitive to changes occurring” there. Taking all these together, they can account for the massive shift in the North Pole. But don’t worry much. This won’t affect your daily life, as long as NASA and other companies account for the changes to keep satellites and your GPS accurate. But it is notable that seemingly minor shifts in water distribution around the world can have profound effects on occurrences in our everyday lives, and that the effects of climate change are far more wide-ranging than simply measuring rising or falling water sea levels. As weather patterns continue to become more extreme, we can expect more changes, and likely some won’t be as innocuous as shifting the geographic North Pole.