True Polar Wander (TPW) ( UPSC Prelims)

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News Context

A new study has shown that the construction of dams has caused a shift in Earth's rotational axis by more than 1 meter since 1835, indicating that they have contributed to True Polar Wander (TPW).

About True Polar Wander (TPW) or planetary reorientation

Rotation of the solid Earth, including the crust and mantle, occurs around the liquid outer core. This process aids in maintaining the Earth's rotational balance due to the redistribution of mass.
 Natural factors influencing True Polar Wander (TPW) include glacial melting, ice sheet melt, tectonic plate shifts, and ocean swell.
 Effects of Shifting Poles:
      ○ They impact satellites and space telescopes, which rely on Earth's rotation for precise positioning.
  ● Longer days result as melting ice transfers mass from the poles to the equator, causing the Earth to become slightly more flattened. This change slows down Earth's spin, leading to longer days. Since 2000, days have been lengthening by 1.33 milliseconds every 100 years, a rate faster than in the previous century.