Climate Change Impact: According to a study in Geophysical Research Letters by the American Geophysical Union (AGU), the Earth’s axis of rotation has been shifting more than usual since the 1990s. This movement is attributed to the substantial melting of glaciers caused by rising global temperatures. Although this shift isn’t predicted to have a noticeable impact on our daily lives, it could slightly alter the length of a day by a few milliseconds.

Concept of Earth’s Axis of Rotation and Polar Motion

• Earth spins around like a top, and the imaginary line it spins around is called its axis of rotation.
• The top and bottom points on Earth where this axis touches the surface are the north and south poles that we see on maps.
• Sometimes, the way Earth’s mass is spread out changes, and this affects how the axis points. As a result, the poles also shift, and this phenomenon is called polar motion.
• Imagine Earth like a spinning ball. If we move some of its weight from the top (the poles) towards the middle (the equator), the spinning slows down a bit. The opposite happens if we shift weight towards the poles – it speeds up the spin.

Key Finding of the Study

• Since the mid-1990s, melting glaciers have been moving a lot of water around.
• This water movement is messing with the regular polar wander, making it shift eastward and speed up.
• Between 1995 and 2020, the average speed of this drift increased a whopping 17 times!
• The main reason for this polar drift is the loss of water from the Polar Regions, and even water loss from other areas adds to this eastward shift.

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Major Factors Causing the shift in Earth’s axis of rotation

The way our planet spins can be influenced by changes in its mass distribution, like shifts in soil, ice, seas, and movements within the Earth’s mantle. Two major factors behind this are the melting of glaciers and excessive groundwater pumping.

• Climate change is making glaciers melt, sending huge amounts of ice into the oceans and causing shifts in the Earth’s poles.
• On the other hand, when we pump too much groundwater, especially in non-glacial areas, it not only changes the storage of water in the ground but also contributes to the movement of the planet’s mass, affecting how it rotates.

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