[DAY 20] 60 DAY RAPID REVISION (RaRe) SERIES for UPSC Prelims 2022 – GEOGRAPHY, CURRENT AFFAIRS & CSAT; Test Series, Videos & Notes!

Solution (b)

Basic info:

A river drains the water collected from a specific area, which is called its ‘catchment area’.

An area drained by a river and its tributaries is called a drainage basin.

The boundary line separating one drainage basin from the other is known as the water Divide. 

The catchments of large rivers are called river basins while those of small rivulets and rills are often referred to as watersheds. 

There is, however, a slight difference between a river basin and a watershed.

Watersheds are small in area while the basins cover larger areas. River basins and watersheds are marked by unity. 

What happens in one part of the basin or watershed directly affects the other parts and the unit as a whole. That is why, they are accepted as the most appropriate micro, meso or macro planning regions.

Solution (d)

Basic Info:

The chotanagpur plateau consists of a series of plateaus standing at different levels of elevation. The highest elevation of about 1100m is in the mid-western portion known as the Patlands – high level laterite plateau. From here, the land descends in all directions in a series of steps which are marked by waterfalls across the rivers. 

The plateau is drained by numerous rivers and streams in different directions and presents a radial drainage pattern.

Solution (c)

Basic Info regarding the Indus River System:

It is one of the largest river basins of the world, covering an area of 11,65,000 sq. km (in India it is 321, 289 sq. km and a total length of 2,880 km (in India 1,114 km). The Indus also known as the Sindhu, is the westernmost of the Himalayan rivers in India.

It originates from a glacier near Bokhar Chu (31°15′ Nlatitude and 81°40′ E longitude) in the Tibetan region at an altitude of 4,164 m in the Kailash Mountain range. In Tibet, it is known as ‘Singi Khamban; or Lion’s mouth.

(The Karakoram Range ends on the northern side of the Pangong Tso. The Kailash Range originates from the southern bank and runs northwest to southeast for over 60 km)

After flowing in the northwest direction between the Ladakh and Zaskar ranges, it passes through Ladakh and Baltistan. It cuts across the Ladakh range, forming a spectacular gorge near Gilgit in Jammu and Kashmir. It enters into Pakistan near Chillar in the Dardistan region. 

The Indus receives a number of Himalayan tributaries such as the Shyok, the Gilgit, the Zaskar, the Hunza, the Nubra, the Shigar, the Gasting and the Dras. It finally emerges out of the hills near Attock where it receives the Kabul river on its right bank. 

The other important tributaries joining the right bank of the Indus are the Khurram, the Tochi, the Gomal, the Viboa and the Sangar. They all originate in the Sulaiman ranges. The river flows southward and receives ‘Panjnad’ a little above Mithankot.

The Panjnad is the name given to the five rivers of Punjab, namely the Satluj, the Beas, the Ravi, the Chenab and the Jhelum. It finally discharges into the Arabian Sea, east of Karachi. The Indus flows in India only through the Leh district in Jammu and Kashmir.

Solution (a)

Basic Info:

The Jhelum, an important tributary of the Indus, rises from a spring at Verinag situated at the foot of the Pir Panjal in the south-eastern part of the valley of Kashmir. It flows through Srinagar and the Wular lake before entering Pakistan through a deep narrow gorge. It joins the Chenab near Jhang in Pakistan.

The Chenab is the largest tributary of the Indus. It is formed by two streams, the Chandra and the Bhaga, which join at Tandi near Keylong in Himachal Pradesh. Hence, it is also known as Chandrabhaga. The river flows for 1,180 km before entering into Pakistan.

The Ravi is another important tributary of the Indus. It rises west of the Rohtang pass in the Kullu hills of Himachal Pradesh and flows through the Chamba valley of the state. Before entering Pakistan and joining the Chenab near Sarai Sidhu, it drains the area lying between the southeastern part of the Pir Panjal and the Dhauladhar ranges.

The Beas is another important tributary of the Indus, originating from the Beas Kund near the Rohtang Pass at an elevation of 4,000 m above the mean sea level. The river flows through the Kullu valley and forms gorges at Kati and Largi in the Dhaoladhar range. It enters the Punjab plains where it meets the Satluj near Harike.

The Satluj originates in the Rakas lake near Mansarovar at an altitude of 4,555 m in Tibet where it is known as Langchen Khambab. It flows almost parallel to the Indus for about 400 km before entering India, and comes out of a gorge at Rupar. It passes through the Shipki La on the Himalayan ranges and enters the Punjab plains. It is an antecedent river. It is a very important tributary as it feeds the canal system of the Bhakra Nangal project.

Solution (b)

Basic Info: 

Ganga River System:

It rises in the Gangotri glacier near Gaumukh (3,900 m) in Uttarakhand where it is known as as Bhagirathi. 

At Devprayag, the Bhagirathi meets the Alaknanda hereafter, it is known as the Ganga.
The Ganga enters the Northern plains at Haridwar.

Ganga flows through the states of Uttarakhand, Uttar Pradesh, Bihar and West Bengal. The Ganga basin covers about 8.6 lakh sq. km area in India alone. It is the largest river system in India having a number of perennial and non-perennial rivers originating in the Himalayas in the north and the Peninsula in the south, respectively. The Son is its major right bank tributary.

Son is the major right bank tributary and the important left bank tributaries are Ramganga, Gomati, Ghaghara, Gandak, Kosi and Mahananda.

Yamuna is the western most and the longest tributary of the Ganga and has its source in the Yamunotri glacier.

Ganga flows into the Bay of Bengal near the Sagar Island.

Solution (c)

Basic Info:

The Brahmaputra, one of the largest rivers of the world, has its origin in the Chemayungdung glacier of the Kailash range near the Mansarovar lake. From here, it traverses eastward longitudinally for a distance of nearly 1,200 km in a dry and flat region of southern Tibet, where it is known as the Tsangpo, which means ‘the purifier.’ 

The Rango Tsangpo is the major right bank tributary of this river in Tibet. It emerges as a turbulent and dynamic river after carving out a deep gorge in the Central Himalayas near Namcha Barwa (7,755 m).

The river emerges from the foothills under the name of Siang or Dihang. It enters India
west of Sadiya town in Arunachal Pradesh. Flowing southwest, it receives its main left
bank tributaries, viz., Dibang or Sikang and Lohit; thereafter, it is known as the Brahmaputra.

Its major left bank tributaries are the Burhi Dihing and Dhansari (South) whereas the important right bank tributaries are the Subansiri, Kameng, Manas and Sankosh. The Subansiri which has its origin in Tibet, is an antecedent river. 

Solution (c)

Basic Info:

Three major geological events in the distant past have shaped the present drainage systems of Peninsular India: 

(i) Subsidence of the western flank of the Peninsula leading to its submergence below the sea during the early tertiary period. Generally, it has disturbed the symmetrical plan of the river on either side of the original watershed.

(ii) Upheaval of the Himalayas when the northern flank of the Peninsular block was subjected to subsidence and the consequent trough faulting. The Narmada and The Tapi flow in trough faults and fill the original cracks with their detritus materials. Hence, there is a lack of alluvial and deltaic deposits in these rivers.

(iii) Slight tilting of the Peninsular block from northwest to the southeastern direction gave orientation to the entire drainage system towards the Bay of Bengal during the same period. 

Solution (a)

Basic Info:

The Himalayan drainage system has evolved through a long geological history. It mainly
includes the Ganga, the Indus and the Brahmaputra river basins. Since these are fed both by melting of snow and precipitation, rivers of this system are perennial. 

These rivers pass through the giant gorges carved out by the erosional activity carried on simultaneously with the uplift of the Himalayas. Besides deep gorges, these rivers also form V-shaped valleys, rapids and waterfalls in their mountainous course. 

While entering the plains, they form depositional features like flat valleys, ox-bow lakes, flood plains, braided channels, and deltas near the river mouth.

In the Himalayan reaches, the course of these rivers is highly tortous, but over the plains they display a strong meandering tendency and shift their courses frequently.

Solution (b)

Basic Info:

Drainage Patterns:
In a trellis pattern, the river forms a netlike system and the tributaries flow roughly parallel to each other and secondary tributaries join them at right angles.

Radial drainage patterns form when rivers originate from a hill and flow in all directions.

A drainage pattern that looks like tree branches with lots of twigs is known as dendritic drainage pattern.

The centripetal drainage pattern is formed when rivers discharge their waters from all directions into a lake or a depression.

Solution (b)

Basic Info: Factors Determining the Climate of India 

Latitude: The Tropic of Cancer passes through the central part of India in the east-west direction. Thus, the northern part of India lies in the sub-tropical and temperate zone and the part lying south of the Tropic of Cancer falls in the tropical zone. The area  north of the Tropic of Cancer being away from the equator, experiences extreme climate with high daily and
annual range of temperature.

The Himalayan Mountains: The towering mountain provides an invincible shield to protect the subcontinent from the cold northern winds. These cold and chilly winds originate near the Arctic circle and blow across central and eastern Asia. The Himalayas also trap the monsoon winds, forcing them to shed their moisture within the subcontinent.

Distribution of Land and Water: India is surrounded by the Indian Ocean on three sides in the south and girdled by a high and continuous mountain-wall in the north. As compared to the landmass, water heats up or cools down slowly. This differential heating of land and sea creates different air pressure zones in different seasons in and around the Indian subcontinent. The difference in air pressure causes a reversal in the direction of monsoon winds.

Distance from the Sea:  Areas in the interior of India are far away from the moderating influence of the sea. Such areas have extremes of climate. On the other hand, the
seasonal contrasts in weather at places in the interior of the country such as Delhi, Kanpur, and Amritsar affect the entire sphere of life.

Altitude: Temperature decreases with height. Due to thin air, places in the mountains are cooler than places on the plains. For example, Agra and Darjiling are located on the same latitude, but the temperature of January in Agra is 16°C whereas it is only 4°C in Darjiling.

Relief: The physiography or relief of India also affects the temperature, air pressure, direction and speed of the wind and the amount and distribution of rainfall. The windward sides of the Western Ghats and Assam receive high rainfall during June-September whereas the southern plateau remains dry due to its leeward situation along the Western Ghats.

Solution (a)

Basic Info:

Mechanism of Weather in the Summer Season
Surface Pressure and Winds: As the summer sets in and the sun shifts northwards, the wind circulation over the subcontinent undergoes a complete reversal at both, the lower as well as the upper levels. By the middle of July, the ITCZ shifts northwards, roughly parallel to the Himalayas between 20° N and 25° N. By this time, the westerly jet stream withdraws from the Indian region.

The ITCZ being a zone of low pressure, attracts inflow of winds from different directions. The maritime tropical airmass (mT) from the southern hemisphere, after crossing the equator, rushes to the low pressure area in the general southwesterly direction. It is this moist air current which is popularly known as the southwest monsoon.

Jet Streams and Upper Air Circulation : The pattern of pressure and winds as mentioned
above is formed only at the level of the troposphere. An easterly jet stream flows over the southern part of the Peninsula in June, and has a maximum speed of 90 km per hour.

In August, it is confined to 15 degrees N latitude, and in September up to 22 degrees N latitudes.

The easterlies normally do not extend to the north of 30 degrees N latitude in the upper atmosphere.

Easterly Jet Stream and Tropical Cyclones: The easterly jet stream steers the tropical depressions into India. These depressions play a significant role in the distribution of monsoon rainfall over the Indian subcontinent. The tracks of these depressions are the areas of highest rainfall in India. The frequency at which these depressions visit India, their direction and intensity, all go a long way in determining the rainfall pattern during the southwest monsoon period.

Solution (c)

Basic Info:

EI-Nino and the Indian Monsoon:

EI-Nino is a complex weather system that appears once every three to seven years, bringing drought, floods and other weather extremes to different parts of the world.

The system involves oceanic and atmospheric phenomena with the appearance of warm currents off the coast of Peru in the Eastern Pacific and affects weather in many places including India.

EI-Nino is merely an extension of the warm equatorial current which gets replaced temporarily by cold Peruvian current or Humbolt current. This current increases the temperature of the water on the Peruvian coast by 10°C. 

This results in:

• The distortion of equatorial atmospheric circulation
• Irregularities in the evaporation of seawater
• Reduction in the number of planktons which further reduces the number of fish in the sea.

The word EI-Nino means ‘Child Christ’ because this current appears around Christmas in December. December is a summer month in Peru (Southern Hemisphere).

EI-Nino is used in India for forecasting long range monsoon rainfall. In 1990-91, there was a wild EI-Nino event and the onset of southwest monsoon was delayed over most parts of the country ranging from five to twelve days.

Solution (d)

Basic Info:

Southern Oscillation Index and Indian Monsoons:

It is a see-saw pattern of meteorological changes observed between the Eastern Pacific and Western Pacific. When the Pressure is high over the equatorial Eastern Pacific, it is low over the equatorial Western Pacific and vice versa.

The pattern of low and high pressures gives rise to vertical circulation along the equator with its rising limb over the low-pressure area and descending limb over the high-pressure area. This is known as Walker Circulation.

It’s shifting eastward from its normal position, such as in El Nino years, reduces monsoon rainfall in India.

Due to the close association between an El Nino (E.N.) and the Southern Oscillation SO the two are jointly referred to as an ENSO event.  The Periodicity of SO is not fixed and its period varies from two to five years.

Southern Oscillation Index (SOD) is used to measure the intensity of the Southern Oscillation.

Solution (c)

Basic Info:

Madden-Julian Oscillation (MJO) is an oceanic-atmospheric phenomenon which affects weather activities across the globe. It brings major fluctuation in tropical weather on weekly to monthly timescales. It’s a traversing phenomenon and is most prominent over the Indian and Pacific Oceans.

The MJO can be characterized as an eastward moving ‘pulse’ of cloud and rainfall near the equator that typically recurs every 30 to 60 days. 

The Indian Ocean Dipole (IOD), El Nino, and MJO are all oceanic and atmospheric phenomena, which affect weather on a large scale. IOD only pertains to the Indian Ocean, but the other two affect weather on a global scale-up to the mid-latitudes.

When it is over the Indian Ocean during the Monsoon season, it brings good rainfall over the Indian subcontinent.

On the other hand, when it witnesses a longer cycle and stays over the Pacific Ocean, MJO brings bad news for the Indian Monsoon.

The presence of MJO over the Pacific Ocean along with an El Nino is detrimental for Monsoon rains.

Solution (b)

Basic Info:

The months of October and November are known for retreating monsoons. By the end of September, the southwest monsoon becomes weak as the low pressure trough of the Ganga plain starts moving southward in response to the southward march of the sun.

The monsoon retreats from the western Rajasthan by the first week of September. It withdraws from Rajasthan, Gujarat, Western Ganga plain and the Central Highlands by the end of the month. By the beginning of October, the low pressure covers northern parts of the
Bay of Bengal and by early November, it moves over Karnataka and Tamil Nadu. By the middle of December, the centre of low pressure is completely removed from the Peninsula.

The retreating southwest monsoon season is marked by clear skies and rise in temperature. The land is still moist. Owing to the conditions of high temperature and humidity, the weather becomes rather oppressive. This is commonly known as the ‘October heat’.

In the second half of October, the mercury begins to fall rapidly, particularly in northern India. The weather in the retreating monsoon is dry in north India but it is associated with rain in the eastern part of the Peninsula. Here, October and November are the rainiest months of the year.

Solution (a)

Basic Info:

Distribution of Rainfall:
The average annual rainfall in India is about 125 cm, but it has great spatial variations.

Areas of High Rainfall: The highest rainfall occurs along the west coast, on the Western Ghats, as well as in the sub-Himalayan areas is the northeast and the hills of Meghalaya. Here the rainfall exceeds 200 cm. In some parts of Khasi and Jaintia hills, the rainfall exceeds 1,000 cm. In the Brahmaputra valley and the adjoining hills, the rainfall is less than 200 cm.

Areas of Medium Rainfall : Rainfall between 100-200 cm is received in the southern parts of Gujarat, east Tamil Nadu, northeastern Peninsula covering Odisha, Jharkhand, Bihar, eastern Madhya Pradesh, northern Ganga plain along the sub-Himalayas and the Cachar Valley and Manipur.

Areas of Low Rainfall: Western Uttar Pradesh, Delhi, Haryana, Punjab, Jammu and Kashmir, eastern Rajasthan, Gujarat and Deccan Plateau receive rainfall between 50-100 cm.

Areas of Inadequate Rainfall: Parts of the Peninsula, especially in Andhra Pradesh, Karnataka and Maharashtra, Ladakh and most of western Rajasthan receive rainfall below 50 cm.

Snowfall is restricted to the Himalayan region.

Solution (c)

Basic Info: 

Some Famous Local Storms of Hot Weather Season

(i) Mango Shower: Towards the end of summer, there are pre-monsoon showers which are a common phenomena in Kerala and coastal areas of Karnataka. Locally, they are known as mango showers since they help in the early ripening of mangoes.

(ii) Blossom Shower: With this shower, coffee flowers blossom in Kerala and nearby areas.

(iii) Nor Westers: These are dreaded evening thunderstorms in Bengal and Assam. Their notorious nature can be understood from the local nomenclature of ‘Kalbaisakhi’, a calamity of the month of Baisakh.

These showers are useful for tea, jute and rice cultivation. In Assam, these storms are known as “Bardoli Chheerha”.

(iv) Loo: Hot, dry and oppressing winds blowing in the Northern plains from Punjab to Bihar with higher intensity between Delhi and Patna.

Solution (d)

Basic Info:

Peninsular Rivers
The Kabini, a tributary of Kaveri, originates in Kerala and flows eastward. The river Kabini joins the Kaveri at Tirumakudal Narasipur.

The Sabarmati is the name given to the combined streams the Sabar and Hathmati. Sabarmati originates from Aravalli hills at an elevation of 762 m near village Tepur, in Udaipur district of Rajasthan. The total length of river from origin to outfall into the Arabian Sea is 371 km. Left bank tributaries: the Wakal, the Hathmati, and the Vatrak. Right bank tributaries: the Sei.

The Mahi basin extends over states of Madhya Pradesh, Rajasthan and Gujarat having total area of 34,842 sq km. It is bounded by Aravalli hills on the north and the north-west, by Malwa Plateau on the east, by the Vindhyas on the south and by the Gulf of Khambhat on the west. Mahi is one of the major interstate west flowing rivers of India. It originates from the northern slopes of Vindhyas at an altitude of 500 m in Dhar district of Madhya Pradesh. The total length of Mahi is 583 km. It drains into the Arabian Sea through the Gulf of Khambhat.

The Sharavathi originates at Ambuthirtha in Thirthahalli Taluk, flows north-west through the Western Ghats. It forms the famous Jog Falls before joining the Arabian Sea at Honavara.

Solution (d)

Basic Info:

Yamuna River System:

It originates from the Yamunotri Glacier on the southwestern slopes or Banderpoonch peak in the Mussoorie range of the lower Himalayas.

Flows along states of Uttarakhand, Himachal Pradesh, Haryana enters Delhi and merges with the Ganga near Triveni Sangam, Allahabad(Prayagraj).

The largest tributary of the Gangain the northern plains. The total length of the Yamuna from its origin till Allahabad is 1,376 km.

It creates the highly fertile alluvial, Yamuna-Ganges Doab region between itself and the Ganges in the Indo-Gangetic plain.

The cities of Bhagpat, Delhi, Noida, Mathura, Agra, Firozabad, Etawah, Hamirpur, and Allahabad lie on its banks.

Some of the Major Tributaries of Yamuna River: Tons, Giri, Hindon, Chambal, Banas, Kali Sindh, Parbati, Sind, Betwa, Dashan, Ken.

The Tons is the longest tributary of the Yamuna River and its flows through Garhwal, the western part of the Himalayan state of Uttaranchal.

The river Giri is an important tributary of the Yamuna River. It is the main source of water in the South-Eastern Himachal Pradesh.

Hindon River is an important tributary of the Yamuna River. In fact, this river is sand-witch between two major rivers: Ganga on the left and Yamuna on the right.

Solution (c)

Basic Info:

The following three factors related to air pressure and wind play a major role in influencing the local climates of India:

Distribution of air pressure and winds on the surface of the earth.

Upper air circulation caused by factors controlling global weather and the inflow of different air masses and jet streams.

The inflow of western cyclones generally known as disturbances during the winter season and tropical depressions during the south-west monsoon period into India, creating weather conditions favourable to rainfall.

Solution (c)

Statement Analysis:

Context – The dam was in news

Solution (a)

Statement Analysis:

Context – The Abhyas High-speed Expendable Aerial Target (HEAT) has been successfully flight- tested by Defence Research and Development Organisation (DRDO) from the Integrated Test Range in Chandipur, off the Bay of Bengal coast in Odisha recently.

Solution (b)

Namdapha National Park is a 1,985 km2 (766 sq mi) large protected area in Arunachal Pradesh of Northeast India. With more than 1,000 floral and about 1,400 faunal species, it is a biodiversity hotspot in the Eastern Himalayas. The national park harbours the northernmost lowland evergreen rainforests in the world at 27°N latitude. The land cover changes with increasing elevation from tropical evergreen forest to temperate broadleaf and mixed forest.

Context – The researchers, from Nature Conservation Foundation (NCF), Mysuru and Centre for Ecological Sciences, Indian Institute of Science, Bengaluru conducted the study on the Hornbill Plateau in Namdapha

Solution (c)

Statement Analysis:

Solution (a)

Statement Analysis:

1. In addition, India will meet 50 percent of its energy requirements from renewable energy by 2030.
2. by the year 2070, India will achieve the target of Net Zero.

Context – National Statement by Prime Minister Shri Narendra Modi at COP26 Summit in Glasgow

Solution (b)

Consider the number as x 

60% of x is 21 less than 3/4 of x 

 i.e) 3/4 of x – 60% of x = 21  

convert percentage into fractions 

(¾)x – (60/100)x = 21  

Taking LCM  

(75x – 60x)/100 = 21  

15x = 21 * 100  

x = 2100/15 = 140

Solution (a)

Number of questions attempted correctly= (60% of 10 + 40% of 30 + 60% of 35)  convert percentage into fractions ((60/100) * 10) + ((40/100) * 25) + ((60/100) * 35) 

Number of questions answered correctly by Sham = 6 + 10 + 21 = 37 questions

Questions to be answered correctly for 60% grade = 60% of 70  convert percentage into fractions (60/100) * 70 = 42 questions  

Therefore, required number of questions = (42 – 37) = 5 questions  

Solution (b)

Let total number of students in the class be 100. 

Indian students = 40% of 100 = 40 

So, foreign students = 100 – 40 = 60

Total number of girls students = 55% of 100 = 55

According to the question, Total number of Indian girl students = 25% of 40 = 10 students 

So, foreign girl students = 55 – 10 = 45

As total foreign students = 60 

So, foreign boy students = 60 – 45= 15

So, percentage of boys among foreign students = (15/60) × 100 = 25%

Solution (c)

Number of married men and women must be equal. 

So, 30% of men = 25% of women 

Let there be 1000 men 

30 % of men = 300 = 25 % of women 

So, 100% of women = 300 * 4 = 1200 women

Hence, there are a total of 2200 adults.

Number of married men = 30% of 1000 = 300

Number of married women = 25% of 1200 = 300 

So, Number of married adults = 300 + 300 = 600 

Percentage of married adults in the population = (600 / 2200) × 100 = 27.2 % 

Hence, the correct answer is option (c).

Solution (c)

Refer to the following lines: “Far from oppressing the cultured minority, or any other minorities, democracy gives more of them more scope to have their way than any other system does.” 

The author clearly mentions that the minorities are given more voice in a democracy which is mentioned in option c.