By Anders Lorenzen
Climate change is now causing such profound impacts that scientists believe that it is shifting the poles and the axis of the Earth.
As glaciers are melting due to climate change, we are likely to witness a shift in the movement of the poles.
Earth’s axis and melting glaciers
The locations of the North and South poles aren’t static, unchanging places on our planet. The axis Earth spins around—or more specifically the surface that the invisible line emerges from—is always moving. However, until now scientists have not been sure why this is happening. But there is now a clearer understanding of which links to climate change because the way water is distributed on Earth’s surface is one factor that drives the drift. A new study in Geophysical Research Letters has found, that the melting glaciers redistributed enough water to cause the poles to turn eastwards during the mid-1990s.
Researchers have been able to determine the causes of polar drifts. This starts from 2002 with data from the Gravity Recovery and Climate Experiment (GRACE), a joint mission by NASA and the German Aerospace Center, which launched twin satellites that year with a follow-up mission in 2018. The mission gathered information on how mass is distributed around the planet by measuring uneven changes in gravity at different points. Previous studies released on the GRACE mission data revealed some of the reasons for later changes in direction.
For instance, research has determined more recent movements of the North Pole away from Canada and toward Russia, due to factors like molten iron in the Earth’s outer core. Other shifts were caused in part by what’s called the terrestrial water storage change, the process by which all the water on land—including frozen water in glaciers and groundwater stored under our continents—is being lost through melting and groundwater pumping.
The shifting of the poles accelerating
One of the authors of the study, Shanshan Deng, a researcher at the Institute of Geographic Sciences and Natural Resources Research at the University of the Chinese Academy of Sciences said: “The faster ice melting under global warming was the most likely cause of the directional change of the polar drift in the 1990s.”
The authors believe there is a clear link proving that climate change is having a profound impact on the shifting of the poles. In 1995 they shifted southward to eastward. In addition, from 1995 to 2020, the average speed of the drift increased about 17 times compared to the average speed from 1981 to 1995.
The researchers used data on glacier loss and estimations of groundwater pumping and calculated how the water stored on land changed. They found that the contributions of water loss from the polar regions are the main driver of polar drift, with contributions from water loss in nonpolar regions. Together, all this water loss explained the eastward change in polar drift.
Another author of the study Suxia Liu, a hydrologist at the same Institute ( Geographic Sciences and Natural Resources Research at the University of the Chinese Academy of Sciences) explained further: “The findings offer a clue for studying past climate-driven polar motion. The goal of this project is to explore the relationship between water and polar motion.” Liu said the research has larger implications for our understanding of land water storage earlier in the 20th century. It could be possible to use those changes in direction and speed to estimate how much land water was lost in past years.
A climate scientist not involved in the study, Vincent Humphrey, a climate scientist at the University of Zurich, remarked how strong this mass change is, “it’s so big that it can change the axis of the Earth,” he said. He did say there is no need to panic as the change to Earth’s axis is not so big as to affect daily life. We are talking about a change only measured by milliseconds.