Climate Change Shifts Earth's Axis: Study
- April, 27, 2021 - 14:14
- World news
TEHRAN (Tasnim) – Melting glaciers redistributed enough water to cause the direction of polar wander to turn and accelerate eastward during the mid-1990s, according to a new study.
The locations of the North and South poles aren't static, unchanging spots on our planet. The axis Earth spins around -- or more specifically the surface that invisible line emerges from -- is always moving due to processes scientists don't completely understand. The way water is distributed on Earth's surface is one factor that drives the drift.
More specifically, the melting of glaciers that's occurred as a result of global warming is the cause of a shift in the Earth's axis that happened in the 1990s. This shift saw the Earth's pole, which is the point where the Earth's rotational axis intersects its crust in the Northern Hemisphere, drift in a "new eastward direction," according to the study, published as part of the American Geophysical Union's geophysical research letters.
To determine how this might have happened, scientists observed two possible theories and their outcomes in relation to the Earth's axis.
"One scenario assumes that the terrestrial water storage change throughout the entire study period (1981-2020) is similar to that observed recently (2002-2020)," the study reads. "The second scenario assumes that it changed from observed glacier ice melting."
According to the study, only the second scenario, along with the atmosphere, oceans, and solid Earth, "agrees with the polar motion during the period of 1981-2020." This new finding, which posits that "the accelerated terrestrial water storage decline resulting from the glacial ice melting is thus the main driver of the rapid polar drift toward the east after the 1990s," indicates that a close relationship between the movement of Earth's poles and climate change exists.
According to SciTechDaily, the direction of polar drift shifted from southbound to eastbound in 1995, and from 1995 to 2020, the average speed of the polar drift, "increased about 17 times the average speed recorded from 1981 to 1995."
To check their theory, the scientists in the study calculated how water stored on land, i.e. glaciers, changed, according to SciTechDaily. The team found that the "contributions of water loss from the polar regions is the main driver of polar drift, with contributions from water loss in non polar regions."
While the team says the planet's axis shift won't affect standard life on Earth – it might have only changed the length of a day by milliseconds, according to SciTechDaily – this study still demonstrates that mass change, in this case glacial, is happening on a scale large enough that the Earth's axis can shift as a result.
"I think it brings an interesting piece of evidence to this question," University of Zurich climate scientist, Vincent Humphrey, told SciTechDaily. "It tells you how strong this mass change is – it's so big that it can change the axis of the Earth."
For more about climate change and its effect on Earth, check out this story about a Google Earth update that lets you see how climate change has drastically altered the planet. Read this story how crystal caves show sea levels were raised 50 feet during a particularly warm period in history after that.