UPSC Mains Answer PYQ 2024: Geography Paper 1 (Section- A) | Geography Optional for UPSC (Notes) PDF Download

Q1: Answer the following in about 150 words each:
(a) What are truncated spurs' ?Where and how are they formed?
Ans: 
Introduction
Truncated spurs are steep, cliff-like landforms that result from glacial erosion. These features mark the transition of river valleys into glacial valleys, showcasing the impact of glaciers on the landscape.

Formation and Characteristics

1. Location: Found in glaciated regions like the Himalayas, Alps, and Norwegian fjords.
2. Process of Formation:
   • Pre-Glacial Phase: Rivers carve interlocking spurs in V-shaped valleys.
   • Glacial Phase: Advancing glaciers erode valley walls through processes like abrasion and plucking.
   • Post-Glacial Phase: The interlocking spurs are truncated, leaving steep, flat-faced cliffs along U-shaped valleys.
3. Features: Typically steep-sided and associated with hanging valleys or waterfalls.

Examples

• Norwegian Fjords: Exhibiting steep-sided valleys formed by glacial erosion.
• Yosemite National Park, USA: Displays U-shaped valleys with truncated spurs.

Conclusion
Truncated spurs are significant geomorphological features, illustrating the transformative power of glaciers and serving as evidence of past glaciation.

(b) Formation of temperate cyclone depends on the condition of axis of dilation. Elucidate.
Ans: 
Introduction
Temperate cyclones, also known as mid-latitude cyclones, form in regions of atmospheric instability due to the interaction of contrasting air masses. The axis of dilation is a critical factor influencing cyclogenesis.

Role of the Axis of Dilation

1. Definition: The axis of dilation is the zone in the upper troposphere where divergence occurs, enabling cyclogenesis.
2. Process of Formation:
   • Convergence at Surface: Warm and cold air masses meet along a polar front.
   • Divergence Aloft: Divergence along the axis of dilation enhances surface low-pressure development.
   • Cyclonic Motion: The Coriolis effect induces rotation, forming a temperate cyclone.
3. Stages of Development:
   • Initial development with a warm front and a cold front.
   • Maturity with occlusion, leading to reduced intensity.

Examples

• The temperate cyclones in Europe bring westerly winds and precipitation.
• Cyclonic systems affecting the US Midwest and Great Plains during winter.

Conclusion
The axis of dilation plays a pivotal role in the dynamics of temperate cyclones, influencing global weather systems and patterns.

(c) With suitable examples explain the factors causing sea level changes.
Ans: 
Introduction
Sea level changes are caused by natural and anthropogenic factors influencing global and regional water levels. These changes impact coastal ecosystems, human settlements, and marine biodiversity.

Factors Causing Sea Level Changes

1. Eustatic Changes (Global Scale):

   • Glacial-Interglacial Cycles: Melting ice during interglacial periods raises sea levels (e.g., post-Ice Age rise).
   • Thermal Expansion: Warmer ocean temperatures expand water volume (e.g., contemporary global warming).
   • Ocean Water Balance: Changes in precipitation and river input affect global sea levels.

2. Isostatic Changes (Local Scale):

   • Tectonic Activity: Land uplift or subsidence due to plate movements (e.g., Scandinavian uplift post-glaciation).
   • Sediment Deposition: Delta regions like the Mississippi River delta experience subsidence.

3. Anthropogenic Factors:

   • Climate Change: Accelerated ice melt from Greenland and Antarctic ice sheets.
   • Coastal Development: Land reclamation and groundwater extraction cause localized subsidence.

Examples

• Maldives: Threatened by rising sea levels due to thermal expansion and ice melt.
• Kiribati: Faces land loss and population displacement due to global warming.

Conclusion
Sea level changes are driven by complex interactions of natural processes and human activities. Understanding these factors is crucial for mitigating risks to coastal communities and ecosystems.

(d) Examine the impacts of social forestry in socio-economic transformation of rural areas.
Ans: 
Introduction
Social forestry refers to community-driven afforestation and forest management initiatives aimed at meeting local needs for fuel, fodder, and timber while improving ecological balance.

Impacts of Social Forestry

1. Economic Benefits:

   • Employment Generation: Tree plantations and forest-related activities create jobs.
   • Livelihood Support: Provides raw materials for cottage industries like sericulture and bamboo crafts.

2. Social Transformation:

   • Community Empowerment: Involves local participation, enhancing decision-making capabilities.
   • Reduction in Rural-Urban Migration: Improved livelihoods reduce the need for migration.

3. Environmental Benefits:

   • Soil Conservation: Reduces erosion and enhances fertility through afforestation.
   • Microclimate Improvement: Increases humidity and reduces temperatures in rural areas.

4. Case Studies:

   • India’s Social Forestry Programme: Initiated in the 1980s, it improved rural incomes and reduced pressure on natural forests.
   • Community Forestry in Nepal: Enhanced biodiversity and rural livelihoods.

Conclusion
Social forestry is a sustainable tool for rural development, addressing socio-economic and environmental challenges while fostering community participation.

(e). Mountain regions are more fragile to ecological changes. Elucidate.
Ans: 
Introduction
Mountain regions are characterized by unique ecosystems, steep gradients, and sensitive biodiversity, making them highly vulnerable to ecological changes.

Reasons for Fragility

1. Topographic Constraints:

   • Steep slopes lead to higher rates of soil erosion and landslides.
   • Limited arable land restricts human activities to marginal areas.

2. Climate Sensitivity:

   • Rapid warming affects glaciers and snowpack (e.g., Himalayas).
   • Changes in precipitation patterns lead to water scarcity.

3. Biodiversity and Ecosystems:

   • High species endemism is susceptible to habitat loss and climate change.
   • Forest degradation impacts hydrological cycles and local livelihoods.

4. Human Activities:

   • Unsustainable tourism, deforestation, and infrastructure development (e.g., Himalayan highways).
   • Overgrazing and shifting cultivation practices exacerbate degradation.

Examples

• Himalayas: Glacial retreat impacts water availability and increases disaster risks.
• Andes: Deforestation and mining threaten biodiversity and ecosystems.

Conclusion
The ecological fragility of mountain regions necessitates sustainable management practices to mitigate the adverse effects of environmental and human-induced changes.

Q2: (a) Examine the recent views on mountain building process and divide the world mountains on the basis of their genesis.
Ans: 
Introduction
The mountain-building process, or orogeny, has evolved with advancements in plate tectonic theory. Mountains can be classified based on their origin, which reflects tectonic, volcanic, or erosional forces.

Recent Views on Mountain-Building

1. Plate Tectonics Theory:

   • Convergent plate boundaries create fold mountains (e.g., Himalayas).
   • Subduction zones result in volcanic mountains (e.g., Andes).

2. Isostasy:

   • Post-glacial rebound contributes to mountain uplift.

3. Geophysical Insights:

   • Seismic studies show crustal thickening and root zones beneath mountains.

4. Climate-Tectonic Interaction:

   • Erosion and climatic factors like monsoons affect mountain heights and stability.

Classification of Mountains by Genesis

1. Fold Mountains:

   • Formed by the collision of tectonic plates.
   • Example: Himalayas (Indian-Eurasian collision), Alps (African-European collision).

2. Volcanic Mountains:

   • Created by volcanic activity.
   • Example: Mount Fuji (Japan), Mount Kilimanjaro (Tanzania).

3. Block Mountains:

   • Formed by faulting and uplift.
   • Example: Vosges (France), Sierra Nevada (USA).

4. Residual Mountains:

   • Result of erosion.
   • Example: Aravallis (India), Scottish Highlands (UK).

5. Dome Mountains:

   • Formed by magma pushing the crust upward.
   • Example: Black Hills (USA).

Conclusion
Understanding mountain genesis helps in studying their role in biodiversity, climate regulation, and human activity. Advances in geophysics and tectonics continue to refine this knowledge.

(b) Describe latitudinal distribution of Köppen's classification of world climate.
Ans: 
Introduction
Köppen’s climate classification system categorizes the world’s climates based on temperature, precipitation, and vegetation. The latitudinal distribution highlights the climatic diversity from the equator to the poles.

Latitudinal Distribution

1. Tropical Climates (A):

   • Found between 0°–23.5° latitude.
   • Example: Tropical Rainforests (Af, Amazon Basin), Savanna (Aw, African Grasslands).

2. Dry Climates (B):

   • Found in subtropical regions (20°–30° latitude).
   • Example: Deserts (BWh, Sahara) and Semi-Arid regions (BSk, Great Plains).

3. Temperate Climates (C):

   • Found between 23.5°–40° latitude.
   • Example: Mediterranean (Cs, Southern Europe), Humid Subtropical (Cfa, Southeastern USA).

4. Continental Climates (D):

   • Found between 40°–60° latitude in the Northern Hemisphere.
   • Example: Siberia (Dfc), North American Plains (Dfa).

5. Polar Climates (E):

   • Found beyond 66.5° latitude.
   • Example: Tundra (ET, Arctic), Ice Cap (EF, Antarctica).

Conclusion
Köppen’s classification is a vital tool for understanding climate distribution, aiding in agriculture, resource management, and environmental conservation.

(c) With suitable sketches elaborate the bottom topography of the Indian Ocean.
Ans:
Introduction
The Indian Ocean's bottom topography is shaped by tectonic activity, sediment deposition, and volcanic processes. Its features influence ocean currents, marine biodiversity, and resource distribution.

Key Features of Indian Ocean Topography

1. Mid-Ocean Ridges:

   • Carlsberg Ridge: Extends north-south, marking tectonic divergence.

2. Abyssal Plains:

   • Flat, sediment-covered regions (e.g., Somali and Arabian Abyssal Plains).

3. Oceanic Trenches:

   • Java Trench: A subduction zone near Indonesia, the deepest part of the Indian Ocean.

4. Seamounts and Plateaus:

   • Chagos-Laccadive Ridge: Submerged volcanic features.
   • Kerguelen Plateau: A large igneous province in the southern Indian Ocean.

5. Marginal Seas:

   • Andaman Sea: Influenced by tectonic activity and sedimentation.

6. Island Chains:

   • Maldives and Seychelles: Coral islands with unique ecosystems.

Conclusion
The Indian Ocean's diverse topography supports rich marine life and underpins significant oceanographic and climatic processes. Effective resource management is critical for its sustainable utilization.

Q3: (a) Explain air masses and associated weather dynamics. How do air masses influence the weather conditions of the Northern Hemisphere?
Ans: 
Introduction
Air masses are large bodies of air with uniform temperature and humidity that influence weather patterns. Their interaction creates dynamic weather phenomena.

Explanation of Air Masses

1. Types of Air Masses:

   • Continental (c): Dry, forming over land (e.g., cT, cP).
   • Maritime (m): Moist, forming over oceans (e.g., mT, mP).
   • Polar (P), Tropical (T), and Arctic (A): Based on latitudinal origin.

2. Associated Weather Dynamics:

   • Cold Fronts: Sudden cooling, thunderstorms (e.g., polar air masses).
   • Warm Fronts: Gradual warming, light rain.
   • Stationary Fronts: Persistent rain and storms.

Influence on Northern Hemisphere Weather

1. North America:

   • Maritime polar air (mP) brings snowstorms to the eastern USA.
   • Continental tropical air (cT) causes heatwaves in summer.

2. Europe:

   • Maritime tropical air (mT) from the Atlantic brings mild, moist winters.

3. Asia:

   • Siberian high-pressure systems (cP) create cold, dry winters in East Asia.

Conclusion
Air masses are critical in shaping regional and seasonal weather dynamics in the Northern Hemisphere. Their study is vital for understanding climatic variability.

(b) "Soil erosion is creeping death." Explaining the statement, suggest various soil conservation measures.
Ans: 
Introduction
Soil erosion refers to the removal of topsoil by wind, water, or human activity. It is termed “creeping death” due to its slow yet devastating impact on soil fertility, food security, and ecosystems.

Explanation of the Statement

1. Loss of Fertility: Topsoil erosion depletes essential nutrients.
2. Desertification: Prolonged erosion leads to barren lands.
3. Reduced Agricultural Productivity: Affects crop yields, threatening livelihoods.
4. Impact on Water Bodies: Sedimentation disrupts aquatic ecosystems.

Soil Conservation Measures

1. Contour Ploughing: Reduces water runoff on slopes.
2. Terracing: Creates step-like structures on hillsides to reduce erosion.
3. Afforestation: Prevents wind and water erosion by stabilizing soil.
4. Crop Rotation and Cover Crops: Enhance soil structure and organic content.
5. Check Dams: Reduce water flow speed, controlling erosion.

Conclusion
Soil conservation ensures sustainable land use, addressing the challenges of food security and environmental degradation.

(c) Perception, Attitude, Value and Emotion (PAVE) are important components for biodiversity and sustainable environmental conservation. Elaborate.
Ans: 
Introduction
PAVE components shape human behavior towards biodiversity and environmental conservation, emphasizing awareness, ethics, and proactive engagement.

Explanation of PAVE

1. Perception:

   • Understanding biodiversity’s importance drives conservation efforts.
   • Example: Community conservation in Western Ghats.

2. Attitude:

   • Positive attitudes foster sustainable practices (e.g., organic farming).

3. Value:

   • Ethical considerations influence resource management (e.g., Chipko Movement).

4. Emotion:

   • Emotional connections with nature promote conservation (e.g., sacred groves in India).

Conclusion
Integrating PAVE into policies and education fosters a collective responsibility for biodiversity and environmental sustainability.

Q4: (a) How is carbon neutrality essential for future environmental conservation? Describe various efforts taken by nations in this regard.
Ans: 
Introduction
Carbon neutrality, or net-zero emissions, involves balancing carbon dioxide emissions with removal or elimination. It is vital to mitigate climate change and ensure sustainable development.

Importance of Carbon Neutrality

1. Climate Stabilization: Reduces global warming and extreme weather events.
2. Ecosystem Preservation: Protects biodiversity and natural habitats.
3. Economic Benefits: Encourages green technologies and reduces fossil fuel dependency.

Global Efforts Towards Carbon Neutrality

1. Paris Agreement (2015): Nations pledged to limit global warming to 1.5°C.
2. European Union: Aims for carbon neutrality by 2050.
3. India: Target of net-zero emissions by 2070.
4. China: Plans to achieve carbon neutrality by 2060.
5. Corporate Initiatives: Companies like Microsoft and Google have pledged net-zero goals.

Conclusion
Achieving carbon neutrality is indispensable for a sustainable future. Collaborative global efforts and individual contributions are essential to this goal.

(b) What is a Yazoo stream? Why are Yazoo basins the areas of repeated flooding? Give examples of Yazoo stream/areas from various parts of the world.
Ans: 
Introduction
A Yazoo stream flows parallel to the main river, blocked by natural levees, before eventually joining it. These streams are often associated with flood-prone regions.

Explanation

1. Formation:
   • Formed when natural levees prevent tributaries from joining the main river directly.
2. Flooding Causes:
   • Poor drainage due to levees.
   • Excessive rainfall or upstream flooding exacerbates waterlogging.

Examples

• Mississippi River Basin (USA): Notable Yazoo streams like the Sunflower and Tallahatchie Rivers.
• Ganges-Brahmaputra Delta (India-Bangladesh): Frequent flooding in adjacent basins.

Conclusion
Proper water management and levee systems are crucial to mitigating flooding in Yazoo basins.

(c) "The latitudinal gradient in species richness is an important geographic trend in biodiversity." Examine the statement.
Ans: 
Introduction
The latitudinal gradient in species richness highlights the concentration of biodiversity near the equator, decreasing towards the poles. This is a significant trend in biogeography.

Explanation

1. Higher Biodiversity in Tropics:

   • Stable climate supports diverse ecosystems (e.g., Amazon Rainforest).
   • Longer evolutionary history allows species diversification.

2. Lower Biodiversity in Polar Regions:

   • Harsh climates limit species survival.
   • Short growing seasons reduce primary productivity.

Examples

• Tropics: Rich coral reefs in the Indo-Pacific.
• Temperate Regions: Moderate species diversity in European forests.

Conclusion
The latitudinal gradient underscores the need to conserve tropical ecosystems, which house the majority of global biodiversity.