The question asks for the origin of the word 'Monsoon'. This is a factual question related to the etymology of a geographical term. To answer this, one needs to recall the historical linguistic origins of common geographical and meteorological terms.
D) Arabic — The word 'Monsoon' is indeed derived from the Arabic word 'Mausim', meaning 'season'. Arab sailors used this term to describe the seasonal reversal of winds in the Indian Ocean, which greatly aided their trade routes.
The Indian monsoon is a complex weather phenomenon driven by large-scale atmospheric circulation. Understanding its fundamental cause requires knowledge of how land and sea surfaces respond to solar radiation differently, leading to pressure gradients that drive wind systems.
Correct Option: C) Differential heating of land and sea is the fundamental cause of the Indian monsoon. This phenomenon creates the necessary pressure gradients that drive the moisture-laden winds from the ocean towards the land.
The question asks for the best definition of the term 'monsoon'. We need to evaluate each option based on the scientific understanding of monsoons.
D) Seasonal reversal of wind direction — This is the most accurate and comprehensive definition of a monsoon. Monsoons are large-scale atmospheric circulations characterized by a seasonal shift in the prevailing wind direction, typically bringing moist air from the ocean to land in summer (wet season) and dry air from land to ocean in winter (dry season).
The Inter-Tropical Convergence Zone (ITCZ) is a low-pressure belt that shifts seasonally with the apparent movement of the sun. During the Indian summer monsoon, the sun is overhead the Tropic of Cancer, causing the ITCZ to move northward over the Indian subcontinent. We need to identify the approximate latitude it reaches during this period.
C) 20°–25° N latitude is the approximate latitude to which the ITCZ shifts northward during the Indian summer monsoon. This position over the Gangetic plains is critical for the establishment and intensity of the monsoon.
The question asks about the role of the Tibetan Plateau in the onset of the Indian monsoon. Understanding the dynamics of the monsoon, especially the thermal and topographical influences, is key to answering this question.
Correct Option: D) Acts as a high-altitude heat source that intensifies the monsoon
This option accurately describes the primary role of the Tibetan Plateau. Its intense heating creates a strong thermal low-pressure system, which draws in and intensifies the monsoon winds, leading to the onset and strengthening of the Indian monsoon.
The question asks about the role of the Tropical Easterly Jet (TEJ) in the Indian monsoon mechanism. To answer this, we need to understand the characteristics of the TEJ and its interaction with the monsoon circulation.
Correct Option: D) It helps strengthen and maintain the monsoon circulation over India