Consider the following statements:Statement I: Scientific studies suggest that a shift is taking pla

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Question

Consider the following statements:Statement I: Scientific studies suggest that a shift is taking place in the Earth's rotation and axis.Statement II: Solar flares and associated coronal mass ejections bombarded the Earth's outermost atmosphere with tremendous amounts of energy.Statement III: As the Earth's polar ice melts, the water tends to move towards the equator.Which one of the following is correct in respect of the above statements?

Accepted Answer

Correct Answer: B - Both Statement II and Statement III are correct but only one of them explains Statement IStep-by-step Solution:Statement I (Claim): Scientific studies indicate that the Earth's rotation and axial position are undergoing a shift. This is factually grounded - research published in journals such as Nature Geoscience has documented changes in Earth's rotation rate and pole wander (true polar wander), partly attributed to melting ice sheets and changes in the distribution of Earth's mass.Evaluating Statement II - Solar flares and CMEs bombard Earth's outermost atmosphere: This is factually correct in isolation - solar flares and coronal mass ejections (CMEs) do interact with Earth's magnetosphere and ionosphere. However, they do not cause shifts in Earth's rotational axis or rotation rate. Solar flares affect communication systems and cause geomagnetic storms, but they do not redistribute mass on Earth or alter its angular momentum sufficiently to change rotation or axis. Therefore, while Statement II is factually true, it does not explain Statement I. ✓ (Factually correct but does NOT explain Statement I)Evaluating Statement III - As polar ice melts, water tends to move towards the equator: This is correct and explains Statement I. When ice melts at the poles, the meltwater redistributes from the poles (high latitudes) to the equatorial oceans (due to gravity and ocean circulation). This redistribution of mass away from the poles changes the Earth's moment of inertia. By conservation of angular momentum, a redistribution of mass away from the rotational axis causes changes in the Earth's rotation rate and can contribute to pole wander (shift in Earth's rotational axis). This is the scientifically established mechanism linking glacial melt to Earth's rotational changes. ✓ (Correct AND explains Statement I)Thus, both Statements II and III are correct, but only Statement III explains Statement I.Why other options are incorrect:Option A: Incorrect. While both II and III are correct, only III explains Statement I. Option A claims both explain it, which is wrong.Option C: Incorrect. Both Statements II and III are correct, not only one.Option D: Incorrect. Both statements are factually correct, so neither is incorrect.Key Concept: Earth's rotation and axis are influenced by the distribution of mass. True Polar Wander (TPW): the drift of Earth's geographic poles relative to the solid Earth, caused by redistribution of mass (melting ice, mantle convection, groundwater depletion). Research (Deng et al., Nature Geoscience) shows that accelerated glacial melt since the 1990s has shifted Earth's pole wander direction. Glacial isostatic adjustment (GIA) also affects the pole. The Chandler wobble is a small, 14-month periodic motion of Earth's axis. Changes in Earth's rotation rate (length of day) are also influenced by atmospheric and oceanic angular momentum transfers.

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