UPSC 1998 Geography Questions with Answers

Explanation

A is correctly matched with 4: Pluto was considered the smallest planet in the solar system. It was reclassified as a dwarf planet in 2006 by the International Astronomical Union (IAU). Note: If we consider only the eight classical planets, Mercury is the smallest. B is correctly matched with 3: Jupiter is the largest planet in the solar system, with a diameter of about 139,820 km. It is a gas giant and has a mass more than twice that of all the other planets combined. It features the iconic Great Red Spot, a giant storm. C is correctly matched with 2: Venus located between Mercury and Earth is the second planet from the Sun. Venus is often called Earth’s "twin" due to its similar size and composition. D is correctly matched with 1: Mercury is the closest planet to the Sun, orbiting at an average distance of 57.91 million km (0.39 AU). It has the shortest orbit of all planets, completing one revolution around the Sun in 88 Earth days.

Explanation

Statement 1 is correct: Asteroids orbit the Sun in an elliptical path, similar to planets. They are rocky remnants from the early formation of the Solar System about 4.6 billion years ago. Their composition includes metals, silicates, and carbon-rich materials.

Statement 2 is correct: Most asteroids are much smaller, typically less than 1 km in diameter. There are millions of asteroids in the Solar System, ranging in size from tiny pebbles to massive bodies.

Statement 3 is incorrect: Most asteroids are located between the orbits of Mars and Jupiter, not Jupiter and Saturn. This region is called the Main Asteroid Belt, which contains the majority of known asteroids. Some asteroids such as Trojan asteroids, share orbits with Jupiter but are not found in the region between Jupiter and Saturn.

Explanation

Option (c) is correct: The correct sequence of the different layers of the atmosphere from the surface of the Earth upwards is: Troposphere Stratosphere Mesosphere Ionosphere Troposphere: This is the lowest layer of the atmosphere, extending from the Earth’s surface up to about 8-15 km. It contains most of the Earth’s weather systems and clouds. Stratosphere: Above the troposphere, this layer extends from around 15 km to 50 km. It contains the ozone layer, which absorbs and scatters ultraviolet solar radiation. Mesosphere: Above the stratosphere, the mesosphere stretches from 50 km to 85 km. It is the layer where meteors burn up upon entry into the Earth’s atmosphere. Ionosphere: This is not a distinct layer like the others but rather a region of the atmosphere (spanning from about 60 km to 1,000 km) where ionization of gases occurs. The ionosphere overlaps with the thermosphere and exosphere.

Explanation

The climate data provided, with moderate temperatures and distinct seasonal rainfall patterns, is more in line with the China-type climate found in parts of Eastern Asia. The temperature gradually increases from 3.9°C in January to 27.8°C in July and then decreases towards December. This shows warm summers and cool winters, which is characteristic of the China-type climate, where summers are typically hot and humid and winters are cold and dry.

Explanation

Option (d) is correct: The 1997 Indonesian forest fires were primarily caused by human activities like slash-and-burn agriculture to clear land for plantations, particularly for palm oil production. These fires escalated due to a lack of effective forest management practises. Options (a), (b) and (c) are incorrect:

The greenhouse effect refers to the trapping of heat in the Earth’s atmosphere by greenhouse gases, leading to global warming. While global warming can influence climate patterns, there is no direct evidence linking the greenhouse effect as the immediate cause of the 1997 fires. The ozone layer protects the Earth from harmful ultraviolet radiation. Its depletion is primarily associated with increased UV exposure. Ozone layer depletion does not have a direct connection to forest fires, including those in Indonesia in 1997. El Niño is a climatic phenomenon characterized by the warming of sea surface temperatures in the central and eastern Pacific Ocean, leading to significant weather changes globally. But it is not directly associated with Indonesian forest fires.

Explanation

Option (a) is correct: Red tides occur due to the excessive growth of dinoflagellates, which are single-celled organisms containing pigments that cause the water to appear reddish or brownish. These blooms can be found in estuaries, coastal areas, and even open ocean waters. Red tides can be dangerous to marine life and humans due to the toxins produced by the dinoflagellates, which can contaminate seafood and pose health risks when consumed.

Option (b), (c) and (d) are incorrect:

Sea tides refers to the regular rise and fall of sea levels due to gravitational forces exerted by the moon and the sun, not to algal blooms. Black tides are typically associated with oil spills in marine environments, leading to a dark discoloration of the water. Sea flowers is not a standard term used in marine science to describe algal blooms.

Explanation

A is correctly matched with 2: Gujarat is the largest producer of cotton in India, followed by Maharashtra. It has favorable black soil and climate conditions for cotton cultivation. B is correctly matched with 1: Madhya Pradesh is the leading producer of gram (chickpea) in India, accounting for a significant share of the total production. C is correctly matched with 4: Kerala is known as the "Spice Garden of India" and is a major producer of black pepper. The state’s humid tropical climate is ideal for growing various spices, including black pepper. D is correctly matched with 3: West Bengal is a major producer of pineapple, particularly in regions like Darjeeling and Jalpaiguri.

Explanation

Option (a) is correct: Bauxite is the primary ore used in the production of alumina, which is then converted into aluminum. India, with its rich bauxite reserves--especially in states like Odisha and Andhra Pradesh--has long been a key exporter of this mineral. Historically, Italy was one of the major importers of Indian bauxite. However, by 1998, market dynamics shifted, and Canada emerged as the leading importer of Indian bauxite. This change is attributed to Canada’s robust aluminum industry, which has a steady demand for alumina, and its favorable trade relations with India.

Explanation

A is correctly matched with 1: Bellary, in Karnataka, India, is known for its graphite deposits. Graphite is a mineral form of carbon used in various industries. B is correctly matched with 4: Zawar, located in Rajasthan, is renowned for its lead-zinc mines. The Zawar mines are among the oldest in India and have been significant sources of lead production. C is correctly matched with 2: Didwana, located in Rajasthan, is known for its salt pans and saline deposits. D is correctly matched with 3: The Rampa region in Andhra Pradesh has been historically associated with silver production, often as a by-product of mining operations.

Explanation

India is the only country in the world which produces all varieties of silk namely tasar, muga and mulberry. India occupies a predominant position in the world and it is the second largest producer of silk after China.

Option (a) is correct: Oak tasar silk is a type of wild silk produced by silkworms that feed exclusively on the leaves of oak trees. It’s known for its unique golden-brown color, durability, and natural luster. The discovery of suitable oak flora in Assam in 1966 significantly boosted the production of Oak tasar silk in the region. By the year 1998, Assam was the largest producer of Oak Tasar Silk. Options (b), (c) and (d) are incorrect:

Tropical tasar is produced in Jharkhand, Chattisgarh, Madhya Pradesh, Orissa and Bihar and to a small extant in Maharashtra, West Bengal and Andhra Pradesh. Assam is renowned for its sericulture industry, especially for muga and eri silks. While the state has favorable conditions for various types of silk production, it is not the leading producer of oak tasar silk.