UPSC Prelims 2013 Analysis

Explanation

Equatorial forests are located within a 5-10 degree band around the equator. They have a hot, humid climate with consistent summer-like weather. These forests have a complex vertical structure, with distinct layers of vegetation and diverse ecosystems.

The tallest trees, known as emergents, dominate the canopy, while the lower layers are home to a variety of plants and animals. Due to high rainfall and a humid climate, these forests provide a suitable environment for the habitat of numerous varieties of fauna and flora. Epiphytes, which are plants that grow on other plants, thrive in tropical equatorial climates because of the above characteristics of equatorial forests.

Explanation

The Atlas Mountains are a mountain range in the Maghreb . It stretches around 2,500 km (1,600 mi) through Morocco, Algeria and Tunisia . The range's highest peak is Toubkal, with an elevation of 4,167 metres (13,671 ft) in southwestern Morocco. It separates the Mediterranean and Atlantic coastlines from the Sahara Desert .

The Abyssinian plateau is in Ethiopia (in Africa).

Guiana Highland is in South America.

Okavango basin/swamp in Southern part of Africa.

Explanation

All of the listed phenomena (1-6) are responsible for bringing dynamic changes on the surface of the Earth.

Electromagnetic Radiation Sunlight drives weather patterns, influences temperatures, and is crucial for plant life (photosynthesis).

Geothermal Energy Heat from the Earth's core fuels volcanic activity, drives plate tectonics, and shapes landforms.

Gravitational Force The Moon's gravity creates tides in our oceans, influencing coastlines and erosion.

Plate Movements The movement of tectonic plates causes mountain formation, earthquakes, and continental drift, constantly reshaping the Earth's surface.

Rotation of the Earth Earth's rotation creates day and night cycles, affecting weather patterns and influencing wind and ocean currents.

Revolution of the Earth Earth's revolution around the Sun causes seasons, impacting temperatures and weather patterns globally.

These forces act together in a complex interplay, constantly sculpting and reshaping the Earth's surface over vast timescales.

Explanation

The most significant characteristic of Indian coal is its high ash content, which varies from 35 to 45 per cent, compared with that of coal in other parts of the world, which is around 15 per cent.

Besides high ash content, another reason for entrained gasifiers (that operate at higher temperatures than fluidised bed gasifiers), commonly used in IGCC plants abroad, being not suitable for Indian coal has a high ash fusion temperature of about 1,500

However, Indian coal's sulphur content is low, about 0.5 per cent.

Explanation

KG basin, Assam, Gulf of Khambhat, Cuddalore district of Tamil Nadu, Barmer in Rajasthan etc. are the areas where natural gas can be found.

Kodarma mines in Jharkhand are one of the important mica producing areas.

The Dharwar rocks are rich in iron ore, manganese, lead, zinc, gold, silver etc. Gondwana is famous for coal fields, not natural gas.

Explanation

The Narmada and the Tapi flow through the rift valley.

Statement 3 is wrong as land slopes to the east in the region.

Statement 2 is factually correct however, is not the reason for the rivers to flow to the west.

Explanation

The most important fishing grounds of the world are found in the regions where warm and cold oceanic currents meet.

Here's why

Nutrient-rich waters When warm and cold currents converge, a process known as upwelling occurs. This upwelling brings nutrient-rich deep ocean water to the surface. These nutrients act like fertilizer for plankton, which forms the base of the marine food chain.

Abundant Marine Life The abundance of plankton attracts a vast array of fish species, making these areas highly productive fishing grounds. Examples include The Grand Banks (Newfoundland) - Labrador Current (cold) meets the Gulf Stream (warm) The Humboldt Current (South America) - cold, nutrient-rich current flowing up the western coast The Canary Current (West Africa) - cold, nutrient-rich current flowing up the western coast

Explanation

The Earth's axis is tilted at an angle of 23.5 degrees relative to its path around the Sun. This tilt means that different parts of the Earth receive direct sunlight for varying lengths of time throughout the year, leading to seasonal changes in day and night length.

Hence the correct answer is (b)

Explanation

According to the U.S. Geological Survey, over 68 percent of the freshwater on Earth is found in ice caps and glaciers, and just over 30 percent is found in groundwater.

Only about 0.3 percent of our freshwater is found in the surface water of lakes, rivers, and swamps.

Explanation

The word Kharif is Arabic for autumn, since the season coincides with the beginning of autumn or winter.

Kharif crops also are known as monsoon crops. These are the crops that are cultivated in the monsoon season. The Kharif season differs in every state of the country but is generally from June to September.

These crops are usually sown at the beginning of the monsoon season around June and harvested by September or October. Rice, maize, bajra, ragi, soybean, groundnut, cotton are all Kharif types of crops.

Explanation

The correct answer is 1 only (Thermal difference between land and water).

Here's why Thermal difference Land heats up and cools down much faster than water. This is because water has a higher specific heat capacity, meaning it takes more energy to heat it up and more energy to cool it down. Coastal areas, being influenced by large water bodies, experience a moderating effect on temperature fluctuations. The temperature changes are more gradual throughout the year.

Variation in altitude (2) While altitude can affect temperature (higher altitude generally means cooler temperatures), this is not the primary reason for the difference between continental interiors and coasts. Both continents and oceans have variations in altitude.

Strong winds (3) Winds can play a role in influencing local temperatures, but their presence wouldn't explain the consistent pattern of higher annual ranges seen in continental interiors.

Heavy rainfall (4) Rainfall patterns can affect temperature to some extent, but coastal areas often receive more rainfall compared to continental interiors. This wouldn't explain the higher annual range observed inland.

Explanation

Steppes are usually characterized by a semi-arid or continental climate. Extremes can be recorded in the summer of up to 45 C (113 F) and in winter, 55 C (67 F). Besides this huge difference between summer and winter, the differences between day and night are also very great.

African Savannah & North American Prairie These regions have more rainfall and varied landscapes compared to the Steppe. Nomadic herding existed, but wasn't the sole way of life.

Siberian Tundra Colder, less rain, permafrost. Not ideal for grazing animals. Nomadic herding is less prevalent.

Therefore, the Central Asian Steppe, with its extreme climate, limited rainfall, and historical dependence on nomadic herding, best fits the description in the statement.

Explanation

Laterite is soil and rock type rich in iron and aluminium but poor in nitrogen, potash, potassium, lime and organic matter and is commonly considered to have formed in hot and wet tropical areas.

• Nearly all laterites are of rusty-red colouration, because of high iron oxide content.
• They develop by intensive and prolonged weathering of the underlying parent rock.
• Tropical weathering (alteration) is a prolonged process of chemical weathering which produces a wide variety in the thickness, grade, chemistry and ore mineralogy of the resulting soils.
• The majority of the land area containing laterites is between the tropics of Cancer and Capricorn.
• Laterite soil commonly found in areas of high altitude and heavy rainfall in Karnataka, TN, MP, Bihar, Orissa, Assam, and Meghalaya.
• Plants like Cashew grow well along with Tapioca in this type of soil.