Physical Geography - Solved Questions (2007- 2024) | UPSC Topic Wise Previous Year Questions PDF Download

Ans: (d)
The Rann of Kutch is a large salt marsh located in the Thar Desert in Gujarat, India. The present day Kutch’s shoreline and the sand dune deposition is the result of hundreds of years of rainless years around 5,000 years ago.

• Due to these severe climate conditions, the sea levels fell, leading to the formation of dunes along the coastline.

Ans: (c)

• The earth’s surface receives most of its energy in short wavelengths. The energy received by the earth is known as incoming solar radiation which in short is termed as insolation.
• The atmosphere is largely transparent to shortwave solar radiation. The incoming solar radiation passes through the atmosphere before striking the earth’s surface. Within the troposphere water vapour, ozone and other gases absorb much of the near infrared radiation.

Hence, statement (c) is correct.

Ans: (d)

• Contrary to the belief that all that vegetation, warmth, and moisture that the soil must be very rich, the soil in tropical rainforests is very poor. Hence, statement 1 is not correct.
• The high temperature and moisture of tropical rainforests cause dead organic matter in the soil to decompose more quickly than in other climates, thus releasing and losing its nutrients rapidly.
• The high volume of rain in tropical rainforests washes nutrients out of the soil more quickly than in other climates. Hence, statement 2 is correct.
• If the soil is so poor in tropical rainforests, how does such a dense array of shrubs and trees grow there? - On the ground of the rainforest, there is a thick layer of quickly decaying plants and animals. Nutrients are washed by the heavy rains almost directly from the rotting surface material into the trees without entering the soil much.

Ans: (a)

• The specific heat is the property of a substance which determines the change in the temperature of the substance (undergoing no phase change) when a given quantity of heat is absorbed (or rejected) by it.
• Water has about four times higher heat capacity than land, i.e. it takes much more energy to increase the water temperature and the water temperature will therefore respond slower to temperature changes. Hence, statement 2 is correct.
• During the summer, the land (continents) heats up more quickly and to a higher temperature than the water (oceans). Therefore, the temperature difference between them is greater. Hence, statement 1 is correct.
• Therefore, both Statement I and Statement II are correct and Statement II is the correct explanation of Statement I.

Ans: (c)

• When an earthquake occurs, two main types of vibratory waves move through the body of the earth from the point of fracture. The primary, or P, waves travel most quickly and are the first to be registered by the seismograph. Secondary, or S, waves travel more slowly. Hence, statement 1 is correct.
  • As S waves have a greater amplitude than P waves the two groups are easily distinguishable on the seismogram.
• Seismic P waves are also called compressional or longitudinal waves, they compress and expand (oscillate) the ground back and forth (to and fro) in the direction of travel, like sound waves.
  • Particle motion is parallel to the direction of propagation (longitudinal). Material returns to its original shape after the wave passes.
• The S waves in an earthquake are examples of Transverse waves.
  • In a transverse wave the particle displacement is perpendicular to the direction of wave propagation. The particles do not move along with the wave; they simply oscillate up and down about their individual equilibrium positions as the wave passes by. Pick a single particle and watch its motion.

Hence, statement 2 is correct.

Ans: (d)
The study of clouds, where they occur, and their characteristics, play a key role in the understanding of climate change. Low, thick clouds primarily reflect solar radiation and cool the surface of the Earth. High, thin clouds primarily transmit incoming solar radiation; at the same time, they trap some of the outgoing infrared radiation emitted by the Earth and radiate it back downward, thereby warming the surface of the Earth.
Hence, both statements are not correct.

Ans: (b)
According to the United Nations Climate Change Conference-COP 26, Lake Faguibine in West Africa has dried up and turned into a desert. Hence option (b) is correct.

Ans: (c)
Gandikota is a Twi village in Cuddapah district of Andhra Pradesh surrounded by the Pennar River on the right, the village is popular for the spectacular valleys formed by the river running through the Erramala hills. The narrow valleys and steep rocky walls with streams running between them look very beautiful. Hence option (c) is correct.

Ans: (b)
Nanda Devi peaks are a part of Kumaon Himalaya.

• The part of Himalaya situated between Sutlej and Kali rivers is known as Kumaon Himalaya.
• The Greater Himalayas extend from Nanga Parbat in the west to Namcha Barwa Peak in the east.
• The Namcha Barwa mountain range comes under Tibet.

Hence option (b) is correct.

Ans: (b)

In the northern hemisphere ‘Second half of the month june (21st june)’ is the longest day of the year. Hence option (b) is correct.

Correct Answer is Option (b)

• Statement 1 is incorrect: With the establishment of the United Nations Convention on the Law of the Sea in 1982 and the entry into force of the ISA in 1994, exploration activities for mineral resources in the area began to be regulated under exploration contracts. Originally, exploration activities were predominantly undertaken by national agencies, until 2010, when private companies became involved and a polymetallic-nodule-mining industry was born.
• Statement 2 is correct: India’s exclusive rights to explore polymetallic nodules from seabed in the Central Indian Ocean Basin (CIOB) have been extended by fi ve years. These rights are over 75000 sq. km of area in international waters allocated by the International Seabed Authority for developmental activities for polymetallic nodules.
• Statement 3 is correct: In 1972, a young ecologist named Hjalmar Thiel ventured to a remote part of the Pacific Ocean known as the Clarion–Clipperton Zone (CCZ). The seafloor there boasts one of the world’s largest untapped collections of rare-earth elements. Some 4,000 meters below the ocean surface, the abyssal ooze of the CCZ holds trillions of polymetallic nodules — potato-sized deposits loaded with copper, nickel, manganese, and other precious ores.

Correct Answer is Option (c)

• Statement 1 is correct. Warmer water is transported westward in the ocean by the Northeast trade winds in the Northern hemisphere of the tropical zone (as the figure given below shows). So, in tropical zones, the western section of ocean is warmer than eastern sections due to trade winds.  
• Statement 2 is correct. Similarly, the Westerlies play an important role in carrying the warm, equatorial waters and winds to the western coasts of continents (that is eastern section of the Oceans in temperate zone). Thus, in temperate zones, westerlies make the eastern section of the ocean warmer than the western sections.  

Correct Answer is Option (d)

• The tropical rainforest is a hot, moist biome where it rains all year long. It is known for its dense canopies of vegetation that form three different layers. The top layer or canopy contains giant trees that grow to heights of 75 m (about 250 ft) or more. This layer of vegetation prevents much of the sunlight from reaching the ground. Thick, woody vines are also found in the canopy. They climb trees in the canopy to reach for sunlight. The middle layer, or understory, is made up of vines, smaller trees, ferns, and palms.
• A large number of plants from this level are used as common houseplants. Because of the small amount of sunlight and rainfall these plants receive, they adapt easily to home environments. The bottom layer or floor of the rainforest is covered with wet leaves and leaf litter. This material decomposes rapidly in the wet, warm conditions (like a compost pile) sending nutrients back into the soil. Few plants are found on the floor of the forest due to the lack of sunlight.

Correct Answer is Option (c)

• Jet streams are high altitude westerly wind system blows at a height of 6 to 14 km, with very high speed up to 450 km/hr in the wavy form at both hemispheres.  So #1 is wrong. 
• The Centre of the cyclone is called an Eye. The eye is a Calm region with no rainfall and experiences the highest temperature and lowest pressure within the cyclonic system.  So  #3 is wrong. So, by elimination, the answer is (c).

Correct Answer is Option (b)

• OMT is measured up to a depth of 26 degrees C isotherm. During January–March, the mean 26 degrees C isotherm depth in the Southwestern Indian Ocean is 59 meters. So, #1 is wrong. 
• Sea surface temperature (SST) is routinely used for predicting whether the total amount of rainfall that India receives during the monsoon season will be less or more than the long-term mean. However, ocean means temperature (OMT) has a better ability to predict this, than SST. So, #2 is correct.

Correct Answer is Option (b)
The favorable weather elements for dew include clear skies, light wind, decent soil moisture. Clear skies allow for the maximum release of longwave radiation to space. Cloudy skies will reflect and absorb while re-emitting longwave radiation back to the surface and that prevents as much cooling from occurring. So (b) is the most appropriate reason.

Correct Answer is Option (d)
As per the NASA webpage: 

• Large amounts of methane are frozen in Arctic tundra soils and in marine sediments including gas hydrates. As Earth's climate warms, that methane is vulnerable to possible release into the atmosphere, where it can add to global warming. So 1 and 2 are correct. 
• In Methane Cycle, every molecule of methane that goes into the atmosphere remains there for 8 years until it is removed by oxidation into carbon dioxide (CO₂) and water (H₂O). So, 3 is also correct. This, answer (d): All three are correct.

Correct Answer is Option (a)

• On 21st June, the Northern Hemisphere is tilted towards the sun. The rays of the sun fall directly on the Tropic of Cancer. So, (c) and (d) are wrong. 
• Places beyond the Arctic Circle experience continuous daylight for about six months. So (a) is correct.

Correct Answer is Option (c)
NCERT Biology Class 12 page 127: “There was no atmosphere on early earth. Water vapor, methane, carbon dioxide, and ammonia released from molten mass covered the surface.” So #2 is wrong, CO2 was present, we are left with (a) or (c). In both options the first statement is correct but experts were divided over the third statement because the early Early atmosphere of earth had no free oxygen, the (life) forms until then could at best be only “anaerobic”. So those living organisms did not have the capacity to alter the atmosphere, at least not in a significant manner. Accordingly, some ticked  ‘a’ while others ticked ‘c’. UPSC has kept ‘c’ as the official answer.

Correct Answer is Option (a)
Studies have shown that increased concentrations of carbon dioxide increase photosynthesis, spurring plant growth…Results showed that carbon dioxide fertilization explains 70 percent of the greening effect. [NASA 2016]

Correct Answer is Option (b)
Sand Mining wrecks the intertidal area and creates the imminent danger of saline water ingress into freshwater." Meaning salinity will increase, so statement 1 is wrong, by elimination we've answer (b) 2 and 3 only. In this question, the first statement is wrong, and you've to identify the right statements. So in real exam stress, some students may have made the error of reading/ticking, and they'd have ticked the wrong option A: only 1. (you're right that it's the wrong statement, but you're not asked to tick the wrong one.) So, be mindful of ticking in OMR.

Correct Answer is Option (b)
The process of decay, added by bacterial action, transforms organic matter into humus. Humus enhances the water retention capacity of the soil. So, 1 is wrong. By elimination, we are left with Answer (b): 3 only.

Correct Answer is Option (a)
Barren Island volcano became active again in March 1991. The second phase of eruptions started in 1995. So it means the third statement is wrong, by elimination, we have the answer (a) only 1.

Correct Answer is Option (b)

• The Hindu: Indian Ocean Dipole (IOD) is an event in which the western Indian Ocean becomes alternately warmer and then colder than the eastern part of the Indian ocean. So the first statement is wrong. 
• A positive IOD leads to greater monsoon rainfall and more active (above-normal rainfall) monsoon days while negative IOD leads to less rainfall and more monsoon break days (no rainfall). So yes, IOD can influence El Nino's impact on Monsoon. So the second statement is right.

Correct Answer is Option (d)
The Brahmaputra enters India in the state of Arunachal Pradesh from its original source Tibet and is joined by the Dibang River and the Lohit River at the head of the Assam Valley. It is joined in Sonitpur by the Kameng River (or Jia Bhoreli). Brahmaputra’s main left bank tributaries, viz., Dibang or Sikang and Lohit. The important right bank tributaries are the Subansiri, Kameng, Manas, and Sankosh. Therefore, all 3 correct.

Correct Answer is Option (a)
The Earth's rotation on its axis explains the eastward flow of the equatorial counter-current. If the earth would have been rotating east to west, the piled-up water would have come down on the west side. Therefore, essentially it's the earth's rotation that explains the eastward flow of equatorial counter current.

Correct Answer is Option (a)
One of the main factors that are responsible for the origin of tropical cyclones is a Large sea surface with temperature higher than 27°C. But in the South Atlantic and South-Eastern Pacific regions, the sea surface temperatures are not enough to form a tropical cyclone formation due to its tendency to remain relatively cooler and this dominates over other factors and prevents any cyclone origination in the region.

Correct Answer is Option (b)
The passage points out the equatorial region.

Correct Answer is Option (d)
Tides are the rise and fall of sea levels caused by the combined effects of gravitational forces exerted by the Moon, Sun, and rotation of the Earth.

Correct Answer is Option (b)
The Westerlies are prevailing winds from the west toward the east in the middle latitudes between 30 and 60 degrees latitude. They originate from the high-pressure areas in the horse latitudes and tend towards the poles and steer extratropical cyclones in this general manner. The moist air masses that cause winter rains in the North-Western region of India are part of westerlies.

Correct Answer is Option (c)
Continental Drift has affected the evolution of animals, the world's geographical positions, and the world's climates. The split of the original super landmass Pangea into Gondwanaland and the Laurasia created new geographical/ climatic regions. The rearrangement and displacement of huge landmasses have helped create the diversity which we see in modern-day species. The final stages of evolution of Genus Homo occur in the last 3 glacial cycles.

Correct Answer is Option (b)
The central Asian steppes run through Kazakhstan, Turkmenistan, Uzbekistan, and Mongolia. The climate here is harsh with dust storms, little to no rainfall, and temperature ranging from – 4 to 50 degrees Celsius.

Correct Answer is Option (a)
The first statement is correct. One major factor affecting the distribution of the temperature of Earth is the distribution of Land and Oceans. Since there is more land in Northern Hemisphere and more waters in the Southern hemisphere and there is a big difference between the specific heat of land and water; the loss of heat from the continents is bigger than the oceans. The continents get heated faster and get cooled faster in comparison to the Oceans. This is the reason that the temperatures of the Oceans are moderate while that of continents is extreme. The moderating effect on the temperature of the land due to the proximity of the seas is called Maritime influence. The increasing effect on the temperature of the land in the interior of the continents is called Continental Influence.

Correct Answer is Option (d)
The canopy is the primary layer of the forest forming a roof over the two remaining layers. The densest of the biodiversity is found here along with a large variety of epiphytes.

Correct Answer is Option (c)
The mixing of warm and cold currents in the region where planktons are found is food for fish. The temperature is just right for them to survive. The temperature is just right for the growth of fish food called planktons.

Correct Answer is Option (d)
From electromagnetic radiation to the revolution of the earth, everything is responsible for bringing dynamic changes to the surface of the earth. For example, Electromagnetic radiation brings changes in the field of microwaves, wavelengths of radio, UV rays, infrared rays, X rays, and gamma rays. Geothermal energy is the heat received from the earth’s core. This heat continuously flows outward. It transfers to the surrounding layers of rock, the mantle. When temperature and pressure become very high some mantle rocks melt becoming magma.  It then either comes out as lava or heats up the nearby rocks and water which comes out as hot springs or geysers. Gravitational force is constantly working on all physical bodies. It is giving weights to objects with mass and causes them to fall to the ground when dropped. Plate movement is a dynamic change on the surface of the earth. It explains many aspects of the interrelationship of volcanoes, earthquakes, climate change, and the evolution of life itself. Everything about our planet is related either directly or indirectly to plate tectonics. Rotation causes day and night. Revolution causes seasons, change in the length of day and night.

Correct Answer is Option (c)
Out of all the water on Earth, saline water in oceans, seas, and saline groundwater make up about 97%  of it. Only 2.5 - 2.75% is fresh water, including 1.75-2%  frozen in glaciers, ice, and snow, 0.5 - 0.75%  as fresh groundwater and soil moisture, and less than 0.01%  of it as surface water in lakes, Swamps, and rivers.

Correct Answer is Option (d)
Variations in the length of daytime and nighttime from season to season are due to the revolution of the earth on a tilted axis.

Correct Answer is Option (b)
Atlas mountain ranges are situated in the northwestern part of Africa. They extend almost 2000 km. They pass through Morocco, Algeria, and Tunisia.

Correct Answer is Option (d)
Savannah covers approximately 20% of the Earth's land area. The largest area of Savannah is in Africa. The tropical Savannah region has a definite dry and wet season. Savannah grasslands are much richer in humus than the equatorial forests.

Correct Answer is Option (c)
The atmosphere is heated by infrared radiation, Moisture is more in the lower atmosphere. In the upper atmosphere, Air is less dense which holds less heat thus temperature is low.

Correct Answer is Option (b)
1. Rotation of the Earth
2. Air pressure and wind
3. Density of ocean water. Revolution has no impact on ocean currents.

Correct Answer is Option (a)
The cosmic microwave background (CMB) is the thermal radiation left over from the "Big Bang". The CMB has well explained as radiation left over from an early stage in the development of the universe and its discovery is considered a landmarks test of the Big Bang model of the universe. Redshift and Blueshift describe how light changes as objects in space (such as stars or galaxies) move closer or farther away from us. The concept is key to charting the universe's expansion.

Correct Answer is Option (c)
Jet flies in the lower stratosphere to avoid turbulence. There are no clouds and the air is dry with little water vapor. There are no vertical winds in the lower stratosphere.

Correct Answer is Option (a)
It is under the influence of cold ocean currents. So given the second statement is wrong.

Correct Answer is Option (a)
The speed of these winds is higher and more persistent in the southern hemisphere. The land mass in the southern hemisphere is lesser in comparison to the northern hemisphere. As these winds cross the landmass its velocity decreases. Thus the effect of westerlies is less over the northern hemisphere than in the southern hemisphere.

Correct Answer is Option (b)
Comets found beyond Nepture i.e. Kuiper belt. Asteroids are tiny planetary bodies revolving around the sun between the orbits of Jupiter and Mars. While comets are made up of small icy particles and Neteoric fragments.

Correct Answer is Option (d)

Correct Answer is Option (b)
Statement 1 is wrong, ionosphere contains charged particles due to which electromagnetic radio waves get reflected and communication becomes possible. Ozone is found mainly in the stratosphere and in traces in the troposphere. Its main function is the absorption of UV rays. While the ions give the ionosphere its name, it is the free electrons that affect the radio waves and radio communications. Also, Radio waves have the longest wave length in the EM spectrum.

Correct Answer is Option (a)
The soils of tropical rainforests are relatively poor in nutrients. Due to torrential rains, most of the nutrients are washed out of the soil, and the soils contain less organic matter than the tropical deciduous forests. Nutrients in the soil are often in forms that are not accessible by plants, unlike tropical deciduous forests where major nutrients remain in the soil. Thus if a tropical rain forest is removed it does not regenerate quickly as compared to a tropical deciduous forest.

Correct Answer is Option (c)
Rotation of the earth causes the wind to deflect towards the left in the Southern Hemisphere.

Correct Answer is Option (a)
Mediterranean climate has mild, rainy winter and hot, dry summers and Evergreen, Oak trees.

Correct Answer is Option (c)
The Albedo of Snow is the highest.

Correct Answer is Option (b)
Normal El Nino forms in the southeastern Pacific whereas El Nino Modoki forms in the central Pacific and causes a greater number of hurricanes.

Correct Answer is Option (d)
Tropical rain forests are warm and humid. The temperature ranges from 21 to 30 degrees Celsius (70 to 85°F) The average annual temperature of tropical rainforests is above 20°C. The tropical rainforests receive annual precipitation amounts of 60 to  160 inches. (152 to 406 cm). Some rainforests in the world experience annual rainfall amounts of almost 400 inches.

Correct Answer is Option (a)
On the earth, the freshwater available for use amounts to about less than 1% of the total water, and its 68.7% is bound up in polar ice and glaciers.

Correct Answer is Option (c)
The core of the earth is made up of nickle and iron.

Correct Answer is Option (a)
Jupiter has maximum moons accounting for 63 whereas Satun has 61, Mars has 2 and Venus has none.

Correct Answer is Option (b)
Jupiter and Saturn are located between Mars and Uranus.

Correct Answer is Option (b)

For India, China, UK, and USA, the correct sequence of the Median age of their population is India < China < USA< UK

Correct Answer is Option (a)
Albedo is the fraction of the incident sunlight that is reflected. When an object reflects most of the light that hits it and looks bright then it has a high albedo. The albedo of mercury is 0.1 and that of the earth is 0.30.

Correct Answer is Option (b)
The maximum and minimum annual temperatures of Ocean water are recorded in August and February respectively in the northern hemisphere. The annual range of temperature is higher in the enclosed seas than in the open sea. The Atlantic Ocean records a relatively higher annual range of temperature than the Pacific Ocean. Since the Northern hemisphere has more landmass as compared to the Southern hemisphere, the annual range of temperature will be greater in the northern hemisphere.

Correct Answer is Option (a)
The horse latitudes are located between latitudes 30°– 35° north and south of the equator. The region lies in an area where there is a ridge of high pressure that circles the earth. The ridge of high pressure is also called a sub-tropical high.