A: Yes, recent research indicates that human activities, specifically large-scale groundwater extraction, have caused the Earth's rotational axis to shift by approximately 31.5 inches (80 cm).
Human activity has had a surprising and profound impact on Earth's rotation, causing the planet to tilt approximately 31.5 inches (80 cm). This phenomenon, rooted in large-scale groundwater pumping, was identified in a study led by Ki-Weon Seo, a geophysicist at Seoul National University. The research, published in Geophysical Research Letters, highlights how redistributing groundwater affects the planet's rotational axis and contributes significantly to sea-level rise.
The Mechanism of Earth's Tilt
The Earth's rotational axis is sensitive to the distribution of its mass. Groundwater pumping removes water stored underground, redistributing it as it flows into rivers and oceans. This redistribution is akin to adding a tiny weight to a spinning top, subtly altering its rotation. Seo stated, “Earth’s rotational pole actually changes a lot. Our study shows that among climate-related causes, the redistribution of groundwater actually has the largest impact on the drift of the rotational pole”
Key Findings of the Study
Groundwater's Role in Polar Drift: The researchers determined that from 1993 to 2010, humans pumped approximately 2,150 gigatons of groundwater. This redistribution shifted the rotational axis by 31.5 inches.
Midlatitude Influence: Water pumping in midlatitude regions, particularly in western North America and northwestern India, has had the most significant impact. The geographic location of groundwater movement plays a critical role in the degree of the tilt
Connection to Sea-Level Rise: The study found that groundwater pumping contributed approximately 0.24 inches (6 mm) to global sea-level rise during the study period. This reinforces concerns about the environmental implications of unsustainable water use
Broader Climate Implications
This study builds on earlier research from 2016, which first suggested that water redistribution could influence Earth's rotation. In 2024, further research revealed that polar ice melt may also affect Earth's spin. Combined, these findings underline the cumulative effects of human-induced climate changes on planetary systems.