Climatology in India is important part of Geography and its syllabus. Previous Year Question (PYQ) papers are invaluable resources for aspirants preparing for competitive exams like the Union Public Service Commission (UPSC) examinations. In this article we present important PYQ on Climatology.
PYQ on Climatology
Q- The term “Levant” often heard in the news roughly corresponds to which of the following regions? (2022)
(a) Region along the eastern Mediterranean shores
(b) Region along North African shores stretching from Egypt to Morocco
(c) Region along Persian Gulf and Horn of Africa
(d) The entire coastal Mediterranean Sea of areas
Answer- Option A
EXPLANATION
The Levant, derived from the French word “lever” meaning “to rise” like sunrise, refers historically to the area along the eastern Mediterranean coast. It roughly corresponds to present-day Israel, Jordan, Lebanon, Syria, and some neighboring regions.
Q- In the northern hemisphere, the longest day of the year normally occurs in the: (2022)
(a) First half of the month of June
(b) Second half of the month of June
(c) First half of the month of July
(d) Second half of the month of July
Answer- Option B
EXPLANATION
In the northern hemisphere, the longest day of the year normally occurs in the Second half of the month of June. In technical terms, this day is referred to as the summer solstice, the longest day of the summer season. It occurs when the sun is directly over the Tropic of Cancer, or more specifically right over 23.5 degrees north latitude.
Q- Consider the following statements: (2021)
1. In the tropical zone, the western sections of the oceans are warmer than the eastern sections owing to the influence of trade winds.
2. In the temperate Zone, westerlies make the eastern sections of oceans warmer than the western sections
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 and 2
Answer- Option C
EXPLANATION
Statement 1: Warmer water is indeed transported westward in the ocean by the Northeast trade winds in the Northern Hemisphere of the tropical zone. This phenomenon results in the western sections of the ocean being warmer than the eastern sections due to the influence of trade winds.
Statement 2: Similarly, the Westerlies are responsible for carrying warm equatorial waters and winds to the western coasts of continents in the temperate zone. Consequently, in temperate zones, the eastern sections of the ocean are warmer than the western sections due to the effect of the westerlies.
Q- With reference to Ocean Mean Temperature (OMT), which of the following statements is/are correct? (2020)
- OMT is measured up to a depth of 26°C isotherm which is 129 meters in the southwestern Indian Ocean during January — March.
- OMT collected during January — March can be used in assessing whether the amount of rainfall in the monsoon will be less or more than a certain long-term mean.
Select the correct answer using the code given below:
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Answer- Option B
EXPLANATION
The depth at which the 26-degree isotherm is found is typically between 50 and 100 meters, not at 129 meters as stated. Therefore, statement 1 is incorrect. In the period from January to March, the average depth of the 26-degree isotherm in the Southwestern Indian Ocean is approximately 59 meters. Ocean Mean Temperature (OMT) serves as a more reliable indicator of monsoon rainfall compared to Sea Surface Temperature (SST) since it reflects the thermal energy of the ocean. Consequently, statement 2 is correct.
Q- Consider the following statements: (2020)
- Jet streams occur in the Northern Hemisphere only.
- Only some cyclones develop an eye.
- The temperature inside the eye of a cyclone is nearly 10°C lesser than that of the surroundings.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 and 3 only
(c) 2 only
(d) 1 and 3 only
Answer- Option C
EXPLANATION
Jet streams are present in both the Northern and Southern Hemispheres, so statement 1 is incorrect. While extra-tropical cyclones do not always exhibit an eye, mature storms typically possess well-defined eyes. In instances of rapid intensification, storms may form an exceptionally small, distinct, and circular eye, often termed a pinhole eye. Therefore, statement 2 is correct. Contrary to statement 3, the interior of the eye in a tropical cyclone is warmer rather than colder. This warmth fuels the storm’s intensity.
Q- Why are dewdrops not formed on a cloudy night? (2019)
(a) Clouds absorb the radiation released from the Earth’s surface.
(b) Clouds reflect back the Earth’s radiation.
(c) The Earth’s surface would have a low temperature on cloudy nights.
(d) Clouds deflect the blowing wind to ground level
Answer- Option B
EXPLANATION
Dew forms when moisture condenses into water droplets on colder surfaces such as stones, grass, and leaves, rather than in the air above them. It requires specific conditions including a clear sky, calm air, high relative humidity, and cold temperatures during an extended night.
Dew formation necessitates that the dew point, the temperature at which air becomes saturated and water vapor begins to condense, exceeds the freezing point. During clear nights, cooler surfaces like trees and plants allow for increased evaporation and consequently more dew formation.
Conversely, cloudy nights inhibit the cooling of these surfaces as the clouds reflect the Earth’s radiation back, preventing them from reaching the necessary temperature for dew to form.
Q- On 21st June, the Sun (2019)
(a) does not set below the horizon at the Arctic Circle
(b) does not set below the horizon at Antarctic Circle
(c) shines vertically overhead at noon on the Equator
(d) shines vertically overhead at the Tropic of Capricorn
Answer- Option A
EXPLANATION
On 21st June the sun does not below the horizon at the Arctic Cricle.
Q- The Earth’s magnetic field has reversed every few hundred thousand years. (2018)
- When the Earth was created more than 4000 million years ago, there was 54% oxygen and no carbon dioxide.
- When living organisms originated, they modified the early atmosphere of the Earth.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer- Option C
EXPLANATION
Scientists have calculated that Earth’s magnetic field has undergone reversals numerous times over the past three billion years, occurring at least hundreds of times. In the last 20 million years alone, magnetic north and south have flipped approximately every 200,000 to 300,000 years, with the most recent major reversal happening around 780,000 years ago. During the Archaean and Proterozoic eras, which span from 4.5 to 2.5 billion years ago, the early secondary atmosphere comprised carbon dioxide (CO2), methane (CH4), water vapor (H2O), carbon monoxide (CO), nitrogen (N), and hydrogen (H). Therefore, statement 2 is incorrect as carbon dioxide was indeed present.
The emergence of living organisms did not significantly impact the composition of the early atmosphere. Despite this, according to the official answer key, only statements 1 and 3 are considered correct.
Q- With reference to ‘Indian Ocean Dipole (IOD)’ sometimes mentioned in the news while forecasting Indian monsoon, which of the following statements is/are correct? (2017)
- IOD phenomenon is characterised by a difference in sea surface temperature between the tropical Western Indian Ocean and the tropical Eastern Pacific Ocean.
- An IOD phenomenon can influence an El Nino’s impact on the monsoon.
Select the correct answer using the code given below:
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Answer- Option B
EXPLANATION
The Indian Ocean Dipole (IOD) is characterized by the contrast in sea surface temperature between two distinct regions, namely an eastern pole located in the eastern Indian Ocean south of Indonesia, and a western pole situated in the Arabian Sea. Therefore, statement 1 is incorrect.
The IOD significantly influences the climate of countries surrounding the Indian Ocean Basin, such as India and Australia, and plays a crucial role in rainfall variability within this region. In scientific terms, the IOD is classified as a coupled ocean and atmosphere phenomenon, akin to the El Niño–Southern Oscillation (ENSO), albeit occurring in the equatorial Indian Ocean. It is believed that the IOD is linked to ENSO events through the extension of the Walker Circulation to the west and the associated Indonesian throughflow, which is the movement of warm tropical ocean water from the Pacific into the Indian Ocean.
Consequently, negative IOD events often coincide with La Niña occurrences, while positive events are associated with El Niño. Therefore, statement 2 is correct.
Q- In the South Atlantic and South-Eastern Pacific regions in tropical latitudes, cyclone does not originate. What is the reason? (2015)
(a) Sea surface temperatures are low
(b) Inter-Tropical Convergence Zone seldom occurs
(c) Coriolis force is too weak
(d) Absence of land in those regions
Answer- Option B
EXPLANATION
Sea surface temperatures in these regions are slightly cooler than the optimal conditions required for the formation of tropical cyclones.
Additionally, there are consistently high levels of vertical wind shear throughout the year, even during summer. The absence of pre-existing centers of rotation, tropical waves, and the Intertropical Convergence Zone (ITCZ) remaining predominantly at or north of the equator further hinders cyclone formation.
The lack of the ITCZ over the ocean deprives the area of synoptic vorticity and convergence necessary for the development of large-scale spin and thunderstorm activity.
Moreover, the strong wind shear makes it challenging to generate tropical cyclones. In regions like the south Atlantic and South Pacific, where the ITCZ remains near the equator without shifting southward, the absence of this crucial atmospheric feature is a major contributing factor to the scarcity of cyclones. Lower sea temperatures also play a role in inhibiting cyclone formation in these areas.
Q- What explains the eastward flow of the equatorial countercurrent? (2015)
(a) The Earth’s rotation on its axis
(b) Convergence of the two equatorial currents
(c) Difference in salinity of water
(d) Occurrence of the belt of calm near the equator
Answer- Option A
EXPLANATION
The rotation of the Earth from west to east causes water to accumulate on its eastern side due to centrifugal force, resulting in a flow towards the east. This phenomenon explains the eastward direction of the equatorial counter current.
Q- Tides occur in the oceans and seas due to which among the following? (2015)
- Gravitational force of the Sun
- Gravitational force of the Moon
- Centrifugal force of the Earth
Select the correct answer using the code given below.
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Answer- Option D
EXPLANATION
Tides are the periodic rise and fall of the sea level, primarily caused by the gravitational pull of the Moon. The Sun’s gravitational pull and the centrifugal force from the Earth also contribute to tides, albeit to a lesser extent. These gravitational forces, along with meteorological effects such as winds and atmospheric pressure changes, result in the movement of water known as surges.
The tide-generating force arises from the difference between the gravitational attraction of the Moon and the centrifugal force. Tides exhibit variations in frequency, direction, and movement across different locations and times. They are categorized based on frequency into semi-diurnal, diurnal, and mixed tides. Springtides occur when the Sun, Moon, and Earth align, resulting in higher tide heights, typically during a full moon. Neap tides, occurring twice a month, happen when the gravitational forces of the Sun and Moon are at right angles to each other, leading to counteracting effects.
Q- Consider the following pairs: (2014)
Programme/Project : Ministry
1. Drought-Prone Area Programme Ministry of Agriculture
2. Desert Development Programme : Ministry of Environment and Forests
3. National Watershed Development Project for Rainfed Areas : Ministry of Rural Development
Which of the above pairs is/are correctly matched?
(a) 1 and 2 only
(b) 3 only
(c) 1, 2 and 3
(d) None
Answer- Option D
EXPLANATION
The Drought-Prone area Programme, aimed at mitigating drought impacts on various sectors, falls under the Ministry of Rural Development, making Pair 1 incorrect.
Similarly, the Desert Development Programme, focused on combating desertification and minimizing drought effects, is also under the Ministry of Rural Development, rendering Pair 2 incorrect.
The National Watershed Project for rainfed areas, a component of the Pradhan Mantri Krishi Sinchayi Yojana overseen by the Ministry of Agriculture, aims to improve water availability in watershed regions, making Pair 3 incorrect.
Q- The seasonal reversal of winds is the typical characteristic of (2014)
(a) Equatorial climate
(b)Mediterranean climate
(c) Monsoon climate
(d) All of the above climates
Answer- Option C
EXPLANATION
The seasonal reversal of winds is the typical characteristic of Monsoon Climate.
Q- During a thunderstorm, the thunder in the skies is produced by the: (2013)
- meeting of cumulonimbus clouds in the sky
- lightning that separates the nimbus clouds
- violent upward movement of air and water particles
Select the correct answer using the codes given below.
(a) 1 only
(b) 2 and 3
(c) 1 and 3
(d) None
Answer- Option D
EXPLANATION
Thunderstorms occur due to the rapid ascent of warm, moist air, which can happen within warm, moist air masses or at fronts. As this air rises, it cools and condenses, forming towering cumulonimbus clouds that can extend upwards of 20 km (12.45 miles).
Thunderstorms are characterized by these cumulonimbus clouds, which typically form on sunny days but can also develop along cold fronts. However, the focus of this question is on the thunder itself, rather than the storm. Thunder is the result of lightning, which produces immense electrical voltage ranging from 100 million to 1 billion volts and can heat the surrounding air to temperatures of approximately 50,000°F. The rapid expansion caused by the intense heat generates shock waves, resulting in the audible sound we perceive as thunder.
Q- Variations in the length of daytime and night time from season to season are due to (2013)
(a) the earth’s rotation on its axis
(b) the earth’s revolution around the sun in an elliptical manner
(c) latitudinal position of the place
(d) revolution of the earth on a tilted axis
Answer- Option D
EXPLANATION
The duration of daylight, known as day length, varies depending on the location on Earth. For instance, at the equator, approximately 12 hours of daylight are received each day, while at the North Pole, there are periods of 24-hour daylight during summer and total darkness during winter months. This discrepancy in day length is a consequence of Earth’s rotation on its axis, which is tilted at an angle of 23.5 degrees. As Earth orbits the Sun, different parts of the planet experience varying degrees of exposure to sunlight. Regions near the poles spend extended periods either pointed toward or away from the Sun during different seasons, resulting in constant daylight or darkness at latitudes above 66.5 degrees, such as the Arctic and Antarctic regions.
The summer solstice, marking the longest day in the Northern Hemisphere, occurs when the North Pole tilts 23.5 degrees toward the Sun. Conversely, the winter solstice, marking the shortest day in the Northern Hemisphere, happens when the North Pole tilts 23.5 degrees away from the Sun, with the South Pole tilting toward it. During the spring and autumn equinoxes, Earth’s axis is neither tilted toward nor away from the Sun, resulting in equal durations of day and night. These variations in day length throughout the year are a result of Earth’s revolution around the Sun on a tilted axis.
Q- The most important fishing grounds of the world are found in the regions where: (2013)
(a) warm and cold atmospheric currents meet
(b) rivers drain out large amounts of freshwater into the sea
(c) warm and cold oceanic currents meet
(d) continental shelf is undulating
Answer- Option C
EXPLANATION
The convergence zones where warm and cold ocean currents meet provide favorable conditions for the proliferation of plankton, which serves as a primary food source for fish populations.
Q- Consider the following: (2013)
- Electromagnetic radiation
- Geothermal energy
- Gravitational force
- Plate movements
- Rotation of the earth
- Revolution of the earth
Which of the above are responsible for bringing dynamic changes on the surface of the earth?
(a) 1, 2, 3 and 4 only
(b) 1, 3, 5 and 6 only
(c) 2, 4, 5 and 6 only
(d) 1, 2, 3, 4, 5 and 6
Answer- Option D
EXPLANATION
Electromagnetic Radiation: EMR consists of electric and magnetic fields traveling in wave form, ranging from low to high energy. It encompasses radio waves, microwaves, infrared light, visible light, ultraviolet light, x-rays, and gamma rays. It influences various Earth surface processes such as temperature changes, water evaporation leading to precipitation, and the formation of metamorphic rocks.
Geothermal Energy: The internal heat of the Earth, derived from sources like radioactivity, rotational and tidal friction, and primordial heat, drives endogenic geomorphic processes. This energy induces diastrophism and volcanism, leading to unevenness in the Earth’s crust due to variations in geothermal gradients and heat flow.
Gravitational Force: Gravity not only causes downslope movements like mass movements and avalanches but also exerts stresses on Earth’s materials.
Plate Movements: Movement of tectonic plates contributes to processes like continent building and earthquakes.
Rotation of the Earth: Earth’s rotation results in uneven heating, creating pressure differences that form winds. Winds influence phenomena such as rainfall, heat distribution, and ocean currents.
Revolution of the Earth: Earth’s elliptical orbit around the Sun causes variations in sunlight intensity, leading to phenomena like aphelion and perihelion. The gravitational force of the Sun also affects ocean tides.