Consider the following statements about the impact of Western Disturbances on Himalayan ecology and rivers:
1. Winter snowfall in the Himalayan region is primarily caused by Western Disturbances.
2. This snowfall has a detrimental effect on the glacier-fed rivers of northern India.
3. The Western Disturbances are vital for maintaining the water levels of the Himalayan rivers during the dry summer months.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. Western Disturbances deposit snow in the Himalayas, which later melts to feed rivers in summer. Statement 2 is incorrect; the snowfall is highly beneficial, not detrimental, as it sustains the glaciers and perennial rivers of northern India.
Consider the following statements about 'Cherry Blossoms' in the context of Indian weather:
1. They are winter rainfall showers in the Himalayan states that aid apple orchards.
2. They are pre-monsoon showers occurring in regions like Karnataka and Kerala.
3. These showers are highly beneficial for the early flowering of coffee plantations.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. Cherry blossoms (also known as coffee showers) happen in South India just before the monsoon and help coffee plants flower. Statement 1 is incorrect; they are not winter showers in the Himalayas.
Regarding the Monsoon Trough, consider the following statements:
1. It is an elongated area of low pressure running roughly parallel to the Himalayas during the summer season.
2. The spatial distribution of rainfall over northern India is strongly governed by the north-south oscillation of the monsoon trough's axis.
3. When the trough shifts closer to the foothills of the Himalayas, the central plains experience a 'break' or dry spell in monsoon rainfall.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: All three statements are correct. The monsoon trough is a core driver of rainfall distribution in the plains. Its movement to the foothills stops rain in the plains, causing a 'break', while flooding the Himalayan rivers.
Consider the following statements about the definition and historical theories of the Indian Monsoon:
1. The word 'monsoon' is derived from the Arabic word 'Mausim', which literally translates to 'season'.
2. It traditionally refers to the complete seasonal reversal of wind direction over the Indian Ocean and surrounding landmasses.
3. Edmund Halley's classical theory attributes the monsoon entirely to the impact of the Coriolis force, disregarding thermal heating entirely.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. Monsoon comes from 'Mausim' and denotes a wind reversal. Statement 3 is incorrect; Halley's classical theory (1686) is precisely the 'Thermal Concept', which attributes the monsoon to the differential heating and cooling of the massive Asian landmass and the adjacent ocean, not the Coriolis force.
Regarding the Madden-Julian Oscillation (MJO) and its impact on Indian weather, consider the following statements:
1. The MJO is an eastward-moving 'pulse' of cloud and rainfall near the equator that typically recurs every 30 to 60 days.
2. Unlike El Nino, the MJO is a stationary phenomenon that develops and dissipates over the Indian Ocean exclusively.
3. When the active convective phase of the MJO is located over the Indian Ocean, it generally enhances the Indian summer monsoon rainfall.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. The MJO is a moving pulse that brings enhanced rainfall when passing over the Indian Ocean. Statement 2 is incorrect; the MJO is a traveling pattern that moves eastward around the global tropics, not a stationary phenomenon.
Regarding the broader impacts of Western Disturbances, consider the following statements:
1. They are absolutely crucial for the successful development of Rabi crops like wheat in the northwestern plains of India.
2. The precipitation in the higher reaches of the Himalayas falls as snow, sustaining the glaciers that feed perennial northern rivers.
3. These disturbances occasionally travel further eastward and cause winter rainfall as far as the Brahmaputra valley.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: All three statements are correct. Western disturbances provide vital winter rain for agriculture, snow for glaciers, and can penetrate as far east as Northeast India.
With reference to pre-monsoon local storms in India, consider the following statements:
1. Nor'westers or 'Kal Baisakhi' are dreaded evening thunderstorms in Bengal and Assam.
2. These local storms occur during the hot weather season.
3. The showers accompanying these storms are useful for tea, jute, and rice cultivation.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: All three statements are correct. Kal Baisakhi (Calamity of the month of Baisakh) are severe thunderstorms in eastern India during summer that provide crucial moisture for crops like tea, jute, and aus paddy.
With reference to the Tropical Easterly Jet Stream (TEJ), consider the following statements:
1. It forms during the summer months over peninsular India.
2. The presence and strength of the TEJ are associated with good monsoon rainfall over India.
3. It steers extratropical cyclones into the northwestern parts of the Indian subcontinent.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. The TEJ develops due to the heating of the Tibetan Plateau and aids the monsoon. Statement 3 is incorrect; extratropical cyclones (Western Disturbances) are steered by the Westerly Jet Stream, while the Easterly Jet steers tropical depressions into India.
Consider the following statements regarding Jet Streams and the Indian Monsoon:
1. The Subtropical Westerly Jet Stream is positioned entirely north of the Himalayas during the summer season.
2. The northward shift of this jet stream is closely linked to the onset of the Southwest Monsoon.
3. In winter, it bifurcates, with one branch blowing south of the Himalayas, steering Western Disturbances into India.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: All three statements are correct. The migration of the Subtropical Westerly Jet to the north of the Himalayas allows the monsoon to enter India, while its southern branch during winter brings the Western Disturbances.
Consider the following statements about pre-monsoon local winds and storms:
1. 'Loo' winds can sometimes be fatal due to their intensely hot, dry, and desiccating nature across northern India.
2. 'Bardoisila' is a local term used in Assam for severe thunderstorms that occur during this season.
3. 'Mango showers' are pre-monsoon phenomena primarily experienced in the northwestern states of Punjab and Haryana.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. Loo hits the north, and Bardoisila hits Assam. Statement 3 is incorrect; 'Mango showers' are associated with the southern coastal states of Kerala and Karnataka, helping early ripening of mangoes.
Regarding the winter season on the east coast of India, consider the following statements:
1. The Tamil Nadu coast remains completely dry during the winter season.
2. The Northeast monsoon winds pick up moisture from the Bay of Bengal.
3. These winds cause significant rainfall over the Coromandel coast during November and December.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. The retreating/Northeast monsoons pick up moisture over the Bay of Bengal and dump it on the Coromandel coast. Statement 1 is incorrect; the Tamil Nadu coast receives the bulk of its annual rainfall during the winter season.
With reference to the rainfall pattern in peninsular India, consider the following statements:
1. During the southwest monsoon, the eastern coast of India, particularly Tamil Nadu, remains relatively dry.
2. This dryness is because the Bay of Bengal branch directly hits the Tamil Nadu coast but lacks moisture.
3. The Tamil Nadu coast lies in the rain shadow area of the Arabian Sea branch of the southwest monsoon.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. Tamil Nadu is in the rain shadow of the Western Ghats for the Arabian branch. Statement 2 is incorrect; the Bay of Bengal branch flows parallel to the Tamil Nadu coast, not directly hitting it, which is why it fails to bring rain during the summer.
With reference to the hot weather season in India, consider the following statements:
1. It is characterized by the apparent northward movement of the sun.
2. 'Loo' are strong, gusty, hot, dry winds blowing during the day over north and northwestern India.
3. The Inter Tropical Convergence Zone (ITCZ) shifts southwards during the hot weather season.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. The hot season is driven by the sun's northward movement, creating extreme heat and the 'Loo' winds. Statement 3 is incorrect; the ITCZ shifts northwards over the Indian landmass during summer, creating a low-pressure trough.
Regarding 'October Heat', consider the following statements:
1. It is a phenomenon characterized by high temperatures and high humidity.
2. It occurs just before the onset of the southwest monsoon in May.
3. During this period, the weather becomes oppressive due to clear skies and high insolation after the monsoon rains.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. Clear skies, waterlogged land, and high temperatures make October weather oppressive. Statement 2 is incorrect; October Heat occurs during the retreating monsoon transition (October-November), not before the summer monsoon in May.
Regarding the winter season in North India, consider the following statements:
1. The winter season in India is dominated by the southwest trade winds.
2. During winter, cyclonic depressions from the Mediterranean Sea cause rainfall in Punjab and Haryana.
3. The northeastern parts of India experience dry winter conditions due to offshore winds.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. Western disturbances bring winter rain to Punjab/Haryana, while offshore winds keep the northeast dry. Statement 1 is incorrect; the winter season is dominated by the northeast trade winds, not the southwest winds.
Regarding the advancing monsoon season, consider the following statements:
1. It is marked by the sudden onset of moisture-laden southwest winds.
2. The Arabian Sea branch of the monsoon reaches the Western Ghats, causing heavy rainfall on the windward side.
3. The 'breaks' in the monsoon are related to the movement of the monsoon trough.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: All three statements are correct. The southwest monsoon advances rapidly, causing orographic rainfall along the Western Ghats. The monsoon trough's movement dictates the wet and dry spells (breaks) during this season.
With reference to the Retreating Monsoon season, consider the following statements:
1. The months of October and November form a period of transition from the hot rainy season to dry winter conditions.
2. The retreat of the monsoon is marked by clearer skies and a brief rise in day temperatures.
3. The low-pressure trough over northwestern India progressively transfers to the Bay of Bengal by early November.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: All three statements are correct. October-November marks the transition characterized by clear skies (causing 'October heat') and the shift of the monsoon trough from land to the Bay of Bengal.
Regarding El Nino and the Indian monsoon, consider the following statements:
1. El Nino involves the abnormal warming of sea surface temperatures in the central and eastern equatorial Pacific.
2. It generally has a suppressing effect on the Indian Summer Monsoon, leading to deficient rainfall.
3. El Nino is a permanent, predictable meteorological phenomenon that occurs exactly every two years.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. El Nino warms the Pacific and suppresses Indian monsoons. Statement 3 is incorrect; El Nino is an irregular phenomenon that typically occurs every two to seven years, not on a strict two-year cycle.
Regarding the interplay between Jet Streams and Indian temperature profiles, consider the following statements:
1. The Sub-tropical Westerly Jet stream causes extreme heating of the Indian landmass by sinking hot air during the summer.
2. The Tropical Easterly Jet stream develops exclusively in summer in response to the intense heating of the Tibetan Plateau.
3. The Easterly Jet steers tropical depressions into the Indian landmass, bringing significant and widespread monsoonal rainfall.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. The Easterly Jet forms due to Tibetan heating and drives monsoon depressions. Statement 1 is incorrect; the Sub-tropical Westerly Jet moves entirely to the north of the Himalayas in summer and does not cause the surface heating of India.
With reference to tropical cyclones and Indian seasons, consider the following statements:
1. Tropical cyclones hit the eastern coast of India with maximum frequency and intensity during the advancing monsoon season in June.
2. The deltas of the Godavari, Krishna, and Kaveri are frequently struck by severe cyclones during the post-monsoon (retreating) season.
3. Cyclonic depressions originating over the Andaman Sea often cross the eastern coast, causing heavy and widespread rainfall.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. The retreating monsoon season (October-November) is highly cyclogenic in the Bay of Bengal. Statement 1 is incorrect; tropical cyclones are least frequent during the peak advancing monsoon (June-August) due to high vertical wind shear; they peak in the post-monsoon season.
Consider the following statements about the winter season in India:
1. The average temperature progressively decreases from south to north during the winter season.
2. The peninsular region of India experiences a well-defined and severe winter season due to oceanic cooling.
3. The isotherm of 20°C runs roughly parallel to the Tropic of Cancer during the month of January, demarcating climatic zones.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. Temperatures drop as one moves north, and the 20°C isotherm acts as a rough climatic divide in January. Statement 2 is incorrect; due to the moderating influence of the surrounding oceans and lower latitude, the peninsular region does not have a well-defined, severe winter season.
Regarding the variability and extremities of Indian rainfall, consider the following statements:
1. The coefficient of variation of rainfall is highest in regions of very high rainfall, such as Meghalaya and the Western Ghats.
2. Areas with low average rainfall are more prone to frequent and severe droughts due to this high annual variability.
3. The occurrence of floods is a common feature in the Brahmaputra valley despite its high average rainfall, due to terrain and river dynamics.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. Low rain areas face droughts, while high rain areas face floods. Statement 1 is incorrect; the coefficient of variation (unreliability) of rainfall is highest in regions with the lowest rainfall, such as Rajasthan, Gujarat, and the rain-shadow areas of the Deccan.
Consider the following statements about the mechanism of Western Disturbances:
1. They are driven eastward into the Indian subcontinent by the high-altitude Subtropical Westerly Jet Stream.
2. They are the primary source of heavy torrential downpours in the southern peninsular states during January and February.
3. The arrival of these disturbances is typically heralded by a temporary but noticeable increase in night temperatures in northwestern India.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. They are steered by the westerly jet and increase night temperatures by trapping terrestrial radiation under clouds. Statement 2 is incorrect; Western Disturbances affect northern and northwestern India, not the southern peninsular states.
Regarding the progression of the monsoon in India, consider the following statements:
1. The onset of the southwest monsoon over the Kerala coast always happens strictly on May 15th every year.
2. The monsoon arrives in two main branches: the Arabian Sea branch and the Bay of Bengal branch.
3. The Bay of Bengal branch is deflected westwards by the Himalayas, bringing rain to the Ganga plains.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. The monsoon is divided into two branches, with the Bay of Bengal branch moving up the Ganga plains. Statement 1 is incorrect; the onset over Kerala typically occurs around June 1st, though the date fluctuates slightly each year.
Regarding the Arabian Sea branch of the monsoon and Rajasthan, consider the following statements:
1. The Aravalli Range is aligned parallel to the direction of the Arabian Sea branch of the southwest monsoon.
2. This parallel alignment fails to offer any topographic barrier to the monsoon winds.
3. This is one of the primary reasons for the low rainfall and arid conditions in the Thar Desert of Rajasthan.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: All three statements are correct. Because the Aravallis run parallel to the Arabian Sea monsoon winds, they do not intercept the moisture, causing the winds to pass over Rajasthan without dropping much rain, contributing to the formation of the Thar Desert.
With reference to the Indian Ocean Dipole (IOD), consider the following statements:
1. It involves an oscillation of sea surface temperatures between the western and eastern Indian Ocean.
2. A negative IOD is always highly favorable for the Indian Summer Monsoon.
3. A positive IOD can sometimes compensate for the negative impact of El Nino on Indian monsoons.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. A positive IOD (warmer western Indian Ocean) boosts monsoon rains and can counter El Nino. Statement 2 is incorrect; a negative IOD is detrimental to the Indian Summer Monsoon, whereas a positive IOD is favorable.
With reference to the air masses and pressure systems affecting India, consider the following statements:
1. During winter, the high-pressure area over central Asia drives dry, cold continental air masses into the subcontinent.
2. The Mascarene High is a permanent low-pressure system situated in the Arabian Sea that weakens during summer.
3. The intense low-pressure system formed over the Tibetan plateau during summer actively attracts the southeast trade winds across the equator.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. Winter sees cold air flow south, and summer sees the Tibetan low pull winds north. Statement 2 is incorrect; the Mascarene High is a high-pressure system, not a low-pressure system, and it is located in the southern Indian Ocean, not the Arabian Sea.
Consider the following statements about Nor'westers in Eastern India:
1. They are notorious local storms known as Kal Baisakhi in West Bengal, bringing destructive squalls.
2. These storms typically originate over the Chota Nagpur Plateau and move eastward towards Bengal.
3. They are considered highly detrimental and destructive to the early cultivation of jute and rice.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. Kal Baisakhi originates over Chota Nagpur. Statement 3 is incorrect; despite their destructive winds, the accompanying showers are highly beneficial and necessary for the pre-monsoon cultivation of jute and aus paddy.
With reference to the retreating monsoon season, consider the following statements:
1. It is characterized by clear skies and a sudden drop in temperature known as 'October heat'.
2. The monsoon trough weakens and gradually shifts southwards during this season.
3. This season is associated with the frequent occurrence of tropical cyclones originating in the Bay of Bengal.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. The trough shifts south, and the Bay of Bengal becomes highly cyclonic. Statement 1 is incorrect; 'October heat' is characterized by clear skies and high temperatures coupled with high humidity, not a sudden drop in temperature.
Regarding the Arabian Sea branch of the Southwest Monsoon, consider the following statements:
1. It strikes the Western Ghats and causes heavy orographic rainfall on the western coastal plains and windward slopes.
2. A part of this branch passes over the Saurashtra peninsula and the Kachchh region without causing much rainfall due to the lack of topographic barriers.
3. The Arabian Sea branch is significantly weaker and carries far less moisture than the Bay of Bengal branch.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. The branch drops heavy rain on the Ghats but skips the flat plains of Gujarat. Statement 3 is incorrect; the Arabian Sea branch is actually much stronger and carries more moisture, as it blows over a larger expanse of the ocean before hitting India compared to the Bay of Bengal branch.
Regarding the Mascarene High, consider the following statements:
1. The Mascarene High is a persistent low-pressure system located in the Bay of Bengal.
2. It acts as a primary source of the cross-equatorial southwest monsoon winds.
3. The intensity of the Mascarene High directly impacts the strength of the monsoon rainfall in India.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. The Mascarene High pushes air across the equator into the Indian low-pressure zone. Statement 1 is incorrect; it is a high-pressure system located in the southern Indian Ocean near Madagascar, not a low-pressure system in the Bay of Bengal.
Consider the following statements about the El Nino Southern Oscillation (ENSO):
1. The Southern Oscillation refers to the seesaw pattern of atmospheric pressure between the tropical eastern Pacific and the Indian Ocean/Western Pacific.
2. The negative phase of the Southern Oscillation Index (SOI) is generally associated with El Nino conditions and weak Indian monsoons.
3. ENSO encompasses both the oceanic phenomenon of sea surface temperature changes (El Nino/La Nina) and the atmospheric phenomenon of the Southern Oscillation.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: All three statements are correct. ENSO is a coupled ocean-atmosphere phenomenon. El Nino (oceanic) is linked to a negative Southern Oscillation Index (atmospheric), which traditionally signals poor monsoon rains in India.
With reference to the spatial distribution of annual rainfall in India, consider the following statements:
1. Areas receiving over 200 cm of rainfall prominently include the west coast, Northeast India, and the Himalayan foothills.
2. The interior of the Deccan Plateau receives heavy rainfall due to its high elevation intercepting the monsoon winds.
3. Rajasthan and parts of Gujarat receive scanty rainfall, often accumulating to less than 50 cm annually.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. The west coast and northeast get extreme rain, while the northwest gets very little. Statement 2 is incorrect; the interior of the Deccan Plateau lies in the rain shadow of the Western Ghats, receiving low to moderate rainfall, not heavy rainfall.
With reference to the atmospheric pressure conditions during winter in India, consider the following statements:
1. A high-pressure center builds up over the region north of the Himalayas.
2. Cold winds from this high-pressure area blow towards the low-pressure areas over the oceans to the south.
3. The Himalayas channel these cold winds directly into the Indian subcontinent, freezing the northern plains.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. A Siberian high-pressure system drives winds south. Statement 3 is incorrect; the Himalayas actually act as an impenetrable barrier, blocking the freezing central Asian winds and protecting the Indian subcontinent from severe winters.
With reference to pre-monsoon showers in India, consider the following statements:
1. 'Tea showers' in Assam are strictly winter phenomena brought entirely by Western Disturbances.
2. Pre-monsoon showers are locally known as 'Blossom Showers' in Kerala and nearby areas as they help in the flowering of coffee.
3. These pre-monsoon showers are fundamentally caused by the collision of warm, moist sea breezes with dry land winds during the summer.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. Blossom showers are crucial for coffee plantations, triggered by sea-land breeze collisions in summer. Statement 1 is incorrect; 'Tea showers' (or Bordoisila) in Assam are pre-monsoon summer thunderstorms, not winter phenomena brought by Western Disturbances.
Consider the following statements regarding the cold weather season in India:
1. The cold weather season begins in mid-October across northern India.
2. During this season, the northeast trade winds prevail over the country.
3. Most of the Indian landmass remains dry during this season as winds blow from land to sea.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. During the cold weather season, northeast trade winds blow from land to sea, making most of India dry. Statement 1 is incorrect; the cold weather season typically begins in mid-November in northern India, not mid-October.
With reference to the Indian Ocean Dipole (IOD), consider the following statements:
1. A positive IOD is characterized by warmer than normal sea surface temperatures in the western Indian Ocean near the African coast.
2. A negative IOD brings cooler water to the western Indian Ocean, a condition which generally suppresses the Indian summer monsoon.
3. IOD events can occur independently of the El Nino Southern Oscillation (ENSO) and uniquely impact Indian weather patterns.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: All three statements are correct. The IOD is an independent oscillation. A positive IOD (warm west, cool east) boosts the monsoon, while a negative IOD suppresses it.
With reference to Mawsynram and Cherrapunji, consider the following statements:
1. They receive some of the highest rainfall in the world due to their unique topographic location.
2. They are located in the funnel-shaped Khasi hills of Meghalaya.
3. The Bay of Bengal branch of the monsoon is trapped in these hills, causing massive orographic rainfall.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: All three statements are correct. The funnel shape of the Khasi hills traps the moisture-laden winds of the Bay of Bengal branch, forcing them to rise rapidly and dump phenomenal amounts of orographic rainfall over Mawsynram and Cherrapunji.
Consider the following statements regarding the Inter Tropical Convergence Zone (ITCZ):
1. The ITCZ is a stationary thermal equator that remains fixed at 0 degrees latitude throughout the entire year.
2. In July, the ITCZ shifts significantly northwards and is located around 20°N-25°N latitudes, over the Gangetic plain.
3. The shift of the ITCZ induces the Southern Hemisphere trade winds to cross the equator and turn into the southwest monsoon.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. The ITCZ shifts over the Ganga plain, pulling in the monsoon winds. Statement 1 is incorrect; the ITCZ is highly dynamic and shifts north and south along with the apparent movement of the sun.
Consider the following statements about the Retreating Monsoon transition:
1. The retreating monsoon winds violently blow from the sea to the land, bringing massive moisture to the interior plains.
2. The transition season is marked by oppressive weather commonly termed 'October Heat' due to high temperature and humidity.
3. The eastern coast of India receives a major portion of its annual rainfall during this retreating monsoon season.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. The transition brings October Heat and heavy rain to the Coromandel coast. Statement 1 is incorrect; the retreating monsoon involves northeast trade winds blowing from land to sea, which are generally dry over the interior plains.
Consider the following statements about the origin and path of Western Disturbances:
1. Western Disturbances originate as tropical cyclones in the Mediterranean Sea.
2. They travel eastward across the Middle East and Iran before reaching the Indian subcontinent.
3. Their arrival in India is typically characterized by a sudden increase in the prevailing night temperature.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. They travel east via Iran and trap terrestrial radiation, increasing night temperatures. Statement 1 is incorrect; they are 'extratropical' or 'temperate' cyclones, not tropical cyclones.
Consider the following statements about the mechanism of the Indian Monsoon:
1. The Indian monsoon is often described as a massive system of planetary-scale sea and land breezes.
2. The differential heating and cooling of the vast Asian landmass and the Indian Ocean drives this seasonal reversal of winds.
3. The Coriolis force plays no role in the deflection of the monsoon winds across the equator.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. The monsoon is a giant land-sea breeze caused by differential heating. Statement 3 is incorrect; the Coriolis force is critical, as it deflects the southeast trade winds from the southern hemisphere to the right after crossing the equator, turning them into the southwest monsoon.
Consider the following statements about Western Disturbances:
1. They are extratropical storms originating in the Mediterranean region.
2. They bring heavy torrential rainfall to the Coromandel coast during the summer months.
3. The moisture in these disturbances is primarily picked up from the Mediterranean Sea and the Caspian Sea.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. Western Disturbances are extratropical cyclones that bring moisture from the Mediterranean. Statement 2 is incorrect; they occur in winter, not summer, and they bring precipitation to northwest India, not the Coromandel coast.
With reference to the climatic role of the Himalayas, consider the following statements:
1. They act as an impenetrable climatic divide, protecting the subcontinent from the bitterly cold winds of Central Asia in winter.
2. They deflect the incoming southwest monsoon winds towards the Arabian Sea, depriving northern India of rainfall.
3. The orographic barrier they present forces the monsoon winds to ascend, causing heavy rainfall along their southern slopes.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. The Himalayas protect against winter freeze and force summer orographic rain. Statement 2 is incorrect; they do not deflect winds to the Arabian Sea. Instead, they deflect the Bay of Bengal branch of the monsoon westwards into the Ganga plains, causing rain.
Regarding the timeline of the Indian Monsoon, consider the following statements:
1. The monsoon generally sets in over the Kerala coast by the first week of June under normal atmospheric conditions.
2. The withdrawal of the monsoon typically begins from the northwestern states of India by early September.
3. The withdrawal process of the monsoon is much faster and far more abrupt than its initial onset.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. Onset is early June, and withdrawal begins in September. Statement 3 is incorrect; the withdrawal of the monsoon is a much slower and more gradual process compared to the sudden 'burst' of its onset.
Regarding the characteristics of Monsoonal Rainfall in India, consider the following statements:
1. A large portion of the rainfall received from the southwest monsoons is orographic in nature.
2. The spatial distribution of monsoon rainfall generally shows a declining trend with increasing distance from the sea.
3. The monsoon is characterized by high inter-annual variability in its onset, duration, and total precipitation.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: All three statements are correct. Monsoonal rain is heavily influenced by topography (like the Western Ghats and Himalayas), decreases inland, and is notoriously erratic from year to year.
Regarding the Hot Weather Season (Summer) in India, consider the following statements:
1. The atmospheric pressure drops and is generally low over the northern half of the country during summer.
2. An elongated low-pressure trough extends from the Thar Desert to the Chota Nagpur Plateau during May.
3. Dust storms are an extremely rare phenomenon in Punjab and Haryana during this season.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. Summer heating creates intense low pressure across northern India. Statement 3 is incorrect; dust storms (locally called 'Andhi') are a very common, almost daily occurrence in Punjab, Haryana, and Rajasthan during May.
With reference to the temperature distribution during the Hot Weather Season, consider the following statements:
1. The absolute highest temperatures during May are consistently recorded in the coastal regions of extreme South India.
2. Due to the moderating influence of the ocean, temperatures remain relatively lower in peninsular India compared to the northern plains.
3. The isotherm of 30°C roughly encloses a vast area of the Deccan plateau and northwestern plains during this season.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. Oceans moderate the south, while the interior and north swelter inside the 30°C isotherm. Statement 1 is incorrect; the highest temperatures (often exceeding 45°C) are recorded in the northwestern parts of India (Rajasthan, Punjab, Haryana), not in coastal South India.
Consider the following statements regarding the Bay of Bengal branch of the Southwest Monsoon:
1. The Arakan Hills along the coast of Myanmar deflect a significant portion of this branch towards the Indian subcontinent.
2. The amount of rainfall generated by this branch progressively decreases as it moves westward up the Ganga plain.
3. This branch is primarily responsible for bringing copious rainfall to the leeward side of the Western Ghats.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. The Arakan hills deflect the winds into Bengal, and moisture is lost as they travel west. Statement 3 is incorrect; the Bay of Bengal branch does not cause heavy rainfall on the leeward side of the Western Ghats; it primarily waters the Northeast and the Indo-Gangetic plains.
Consider the following statements about winter rainfall in India:
1. The winter rainfall caused by Western Disturbances in northwest India is locally known as 'Mahawat'.
2. This rainfall is highly beneficial for the cultivation of Rabi crops, especially wheat.
3. These disturbances are steered into India by the tropical easterly jet stream.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. 'Mahawat' is vital for Rabi crops. Statement 3 is incorrect; Western Disturbances are brought into India by the subtropical westerly jet stream, not the tropical easterly jet stream.
Consider the following statements about the Winter season weather in North India:
1. The inflow of Western Disturbances typically causes a fall in minimum temperatures immediately after their passage.
2. The region experiences heavy, continuous monsoonal rainfall for several months straight during the winter season.
3. Frost is commonly observed in the northwestern plains due to nocturnal radiational cooling under clear winter skies.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. Night temperatures fall after a western disturbance passes, and frost is common. Statement 2 is incorrect; winter rainfall from western disturbances is light, intermittent, and highly localized, not heavy or continuous for months.
With reference to the climatic sub-regions based on rainfall, consider the following statements:
1. The Coromandel coast receives the absolute majority of its annual rainfall from the advancing Southwest Monsoon in June and July.
2. The Western Ghats act as a significant orographic barrier, leaving large tracts of the Deccan plateau as a semi-arid rain shadow region.
3. Meghalaya receives immense amounts of rainfall due to its unique funnel-shaped topography trapping the moist monsoon winds.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. The Western Ghats create a rain shadow, and Meghalaya traps moisture. Statement 1 is incorrect; the Coromandel coast stays largely dry during the advancing Southwest Monsoon and receives the bulk of its rain from the Retreating (Northeast) Monsoon in November-December.
Consider the following statements about 'Mango showers':
1. Mango showers are pre-monsoon showers common in Kerala and Karnataka.
2. They help in the early ripening of mangoes in these coastal regions.
3. These showers occur towards the close of the summer season.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: All three statements are correct. Towards the end of the summer season, pre-monsoon showers are common, especially in Kerala and Karnataka. They help in the early ripening of mangoes, hence the name.
With reference to the role of Jet Streams in Indian climate, consider the following statements:
1. The Tropical Easterly Jet Stream blows continuously throughout the year over peninsular India.
2. The Sub-tropical Westerly Jet Stream shifts north of the Himalayas in summer, facilitating the monsoon onset.
3. The Tropical Easterly Jet Stream is responsible for steering tropical depressions into India, heavily influencing monsoon rainfall distribution.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 2 and 3 are correct. The Westerly Jet moves north, and the Easterly Jet steers monsoon depressions. Statement 1 is incorrect; the Tropical Easterly Jet Stream is a seasonal phenomenon that only develops during the summer months due to the intense heating of the Tibetan plateau.
Consider the following statements regarding the 'Break' in the Indian Monsoon:
1. It occurs when the monsoon trough moves northwards towards the Himalayan foothills.
2. During a break, rainfall decreases in the central plains but increases significantly along the Himalayan foothills and Northeast India.
3. The break period is characterized by the frequent formation of intense cyclonic depressions in the Arabian Sea.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. A break in the monsoon happens when the monsoon trough shifts to the Himalayan foothills, causing heavy rain there while the plains remain dry. Statement 3 is incorrect; a break is usually associated with a decline in the formation of cyclonic depressions over the seas.
Regarding the role of the Tibetan Plateau in the monsoon, consider the following statements:
1. The Tibetan Plateau acts as a high-altitude heat source during summer, strengthening the monsoon.
2. The cooling of the Tibetan Plateau is responsible for generating the Somali Jet stream.
3. Intense heating of the Tibetan Plateau helps in the formation of the Tropical Easterly Jet Stream.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. The plateau acts as an elevated heat source, sucking in moisture and forming the Tropical Easterly Jet. Statement 2 is incorrect; the Somali Jet is tied to the Mascarene High and low-level cross-equatorial flow, not the cooling of the Tibetan Plateau.
Consider the following statements about La Nina:
1. La Nina is characterized by unusually cold ocean temperatures in the Equatorial Pacific.
2. It generally leads to drought conditions and deficient rainfall over the Indian subcontinent.
3. La Nina is often associated with stronger than normal southwest monsoon winds in India.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. La Nina involves cold Pacific waters and generally boosts the Indian monsoon. Statement 2 is incorrect; La Nina generally brings above-average rainfall and flood conditions to India, whereas El Nino causes droughts.
With reference to 'Bardoli Chheerha', consider the following statements:
1. It is the local name given to the pre-monsoon thunderstorms in Assam.
2. These storms are synonymous with the 'Kal Baisakhi' experienced in West Bengal.
3. They occur exclusively during the retreating monsoon season in November.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 2 are correct. Bardoli Chheerha are violent pre-monsoon squalls in Assam, akin to Kal Baisakhi. Statement 3 is incorrect; they occur during the hot summer/pre-monsoon season (April-May), not during the retreating monsoon in November.
With reference to the Inter Tropical Convergence Zone (ITCZ), consider the following statements:
1. It is a broad trough of low pressure in equatorial latitudes where trade winds converge.
2. The seasonal shift of the ITCZ over the Ganga plains is a major determinant of the Indian summer monsoon.
3. When the ITCZ shifts over India during summer, it is often referred to as the monsoon trough.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: All three statements are correct. The ITCZ is a low-pressure convergence zone. Its northward migration over the Indian landmass creates the monsoon trough, drawing the moisture-laden southwest winds into the subcontinent.
Consider the following statements about the Somali Jet Stream:
1. It plays a crucial role in intensifying the southwest monsoon winds towards India.
2. It is a high-altitude atmospheric jet stream found at the tropopause.
3. The strength of the Somali Jet is positively correlated with the intensity of the Indian summer monsoon rainfall.
Which of the statements given above are correct?
- 1 and 2
- 2 and 3
- 1 and 3
- All three
Explanation: Statements 1 and 3 are correct. The Somali Jet intensifies the monsoon flow. Statement 2 is incorrect; unlike the subtropical westerly or tropical easterly jets, the Somali Jet is a low-level cross-equatorial flow (LLJ) that occurs closer to the surface.