Water has power. So much power, in fact, that when humans pump groundwater, it can change the tilt of Earth’s rotation. It can also raise sea levels—and now, thanks to groundbreaking research, we know by how much.
Groundwater and Earth’s Tilt: What the Data Reveals
A study published in the journal Geophysical Research Letters has confirmed that groundwater pumping from 1993 to 2010 shifted Earth’s tilt by 31.5 inches (80 cm). That’s more than two and a half feet—enough to demonstrate that the redistribution of water by humans is now measurably affecting the physical orientation of our planet.
This movement is due to the shift in mass. When water is pumped from underground aquifers—primarily for irrigation and human consumption—it doesn’t stay there. It often finds its way into rivers, eventually flowing to oceans and raising sea levels. According to the study, this activity alone has contributed about 0.24 inches (6 mm) to sea level rise.
“Like Adding a Tiny Bit of Weight to a Spinning Top”
The Earth’s axis is not fixed; it wobbles and shifts over time due to changing distributions of mass. “Earth’s rotational pole actually changes a lot,” explains lead author Ki-Weon Seo, a geophysicist at Seoul National University. “Our study shows that among climate-related causes, the redistribution of groundwater actually has the largest impact on the drift of the rotational pole.”
NASA first documented this phenomenon in 2016. This new study builds on that work by attaching real numbers to the theory. By modeling various scenarios from 1993 to 2010, researchers discovered that only the model including the redistribution of 2,150 gigatons of groundwater matched the actual polar drift that occurred during that period.
Where the Water Goes—and Why It Matters
Water movement from the midlatitudes—particularly regions like western North America and northwestern India—has had an outsized impact on Earth’s axial drift. These regions are heavily reliant on groundwater pumping, which has accelerated due to growing agricultural demands and water scarcity.
“Observing changes in Earth’s rotational pole is useful,” Seo says, “for understanding continent-scale water storage variations.” It could also serve as a new lens for evaluating the long-term consequences of our water use habits—and for guiding future conservation strategies.
What This Means for Climate Change
Although sea level rise from groundwater pumping may seem small compared to ice sheet melt, the discovery that it alters Earth’s axis underscores the interconnectedness of all planetary systems. It’s no longer just about how much water we use—it’s about how and where we move it, and the planetary-scale consequences that follow.
“This is important,” says NASA scientist Surendra Adhikari, who was involved in the earlier research. “They’ve quantified the role of groundwater pumping on polar motion—and it’s pretty significant.”
Looking Ahead
If this much drift can occur in just 17 years, what might the next century bring? Further research, including the study of historical groundwater trends, may help scientists refine predictions and mitigation strategies. What’s clear is that conservation and water resource management aren’t just local issues—they are planetary imperatives.
In an era of climate instability, the humble act of drawing water from the ground is emerging as a key driver of global change. The power of water, once again, proves deeper than we ever imagined.
