Model Answer

Tropical cyclones require specific conditions to form and intensify. These conditions are:

1. Warm Sea Surface: The sea surface must be at least 27°C to provide the necessary heat for the formation of these storms.
2. Moist Air: A large sea surface area provides a constant supply of moist air, essential for cloud formation.
3. Coriolis Force: The Coriolis effect is needed to initiate and maintain the spiral motion of the cyclone, which occurs in an anticlockwise direction in the Northern Hemisphere and clockwise in the Southern Hemisphere.
4. Low-Pressure Area: A pre-existing low-pressure area is needed to attract moist air, creating the conditions for a cyclone.
5. Minimal Vertical Wind Shear: Little variation in wind speed and direction at different heights is required to maintain a stable, rotating system.
6. Upper-Level Divergence: Divergence of air at higher altitudes ensures the continued movement of air away from the center, helping to sustain the low-pressure system at the surface.

Differences Between Tropical and Temperate Cyclones

Tropical cyclones are influenced by warm ocean conditions, whereas temperate cyclones are more complex, forming due to temperature contrasts in the atmosphere and a more dynamic air mass movement.

Model Answer

Departmentally Related Standing Committees (DRSCs) play a pivotal role in fortifying India’s parliamentary democracy by enhancing legislative scrutiny, enabling informed decision-making, and fostering accountability. Here’s how they contribute:

1. In-depth Legislative Scrutiny

• Need for scrutiny: The Parliament meets for only about 67 days annually, which limits the time available for detailed legislative discussions. DRSCs, functioning year-round, bridge this gap by closely examining bills and policies (Source: Article text).
• Example: Bills referred to DRSCs undergo rigorous analysis, improving their quality and reducing legislative errors.

2. Providing Technical Expertise

• Complex matters: Parliamentary deliberations often require technical knowledge. DRSCs engage domain experts and government officials for informed recommendations.
• Example: The committees’ consultations with experts on economic and technological policies lead to more robust legislative frameworks (Source: Article text).

3. Consensus Building Across Political Lines

• Closed-door discussions: Unlike televised parliamentary debates, DRSCs meet privately, fostering bipartisan dialogue and consensus.
• Impact: This setting ensures nuanced deliberations free from party biases, strengthening cooperative decision-making (Source: Article text).

4. Ensuring Financial Accountability

• Budget oversight: DRSCs review the Demand for Grants, assess fund utilization, and align spending with policy priorities.
• Example: They scrutinize ministry budgets, ensuring fiscal discipline and resource optimization (Source: Article text).

5. Policy Recommendations

• Action Taken Reports (ATRs): DRSCs suggest policy improvements, monitor government action on recommendations, and evaluate outcomes.
• Example: ATRs ensure government accountability, reinforcing a feedback loop in governance (Source: Article text).

Scope for Improvement

While DRSCs significantly enhance Parliament’s functioning, periodic reviews of their effectiveness and wider discussion of their recommendations in Parliament can further strengthen their impact.

Thus, DRSCs serve as vital pillars of parliamentary democracy, ensuring informed decision-making, accountability, and cross-party collaboration.

Model Answer

Earthquake waves, or seismic waves, are primarily classified into two categories: body waves and surface waves.

Body Waves

Body waves are generated at the earthquake’s focus and travel through the Earth’s interior. They are further divided into:

1. P-waves (Primary Waves):
   • Characteristics: These are the first waves to arrive at the surface, traveling through solids, liquids, and gases. They vibrate in a direction parallel to their path of propagation (Source: Seismology Texts).
2. S-waves (Secondary Waves):
   • Characteristics: S-waves arrive after P-waves and can only move through solids. Their vibrations are perpendicular to the direction of wave travel, creating troughs and crests (Source: Earth Science Resources).

Surface Waves

When body waves reach the surface, they generate surface waves, which move along the Earth’s exterior. There are two types of surface waves:

1. Love Waves:
   • Characterized by side-to-side motion without vertical movement, causing horizontal twisting of the ground.
2. Rayleigh Waves:
   • These waves produce a rolling motion, moving in an elliptical pattern, creating both vertical and horizontal displacements (Source: Geophysical Literature).

Formation of Shadow Zones

Shadow zones are specific areas on Earth where seismic waves are not detected. Seismographs located within 105° of the epicenter record both P and S-waves, while those beyond 145° detect only P-waves. The region between 105° and 145° is the shadow zone for S-waves, encompassing over 40% of the Earth’s surface (Source: Geological Surveys).

The formation of shadow zones is attributed to the Earth’s internal structure, which is heterogeneous and has varying densities. This results in the refraction of P-waves and the complete absence of S-waves beyond certain distances. The existence of shadow zones has aided scientists in determining the boundaries between the Earth’s mantle and core, confirming that the outer core is liquid since S-waves cannot pass through liquids (Source: Seismology Research).

Importance of Weathering

Weathering is crucial for the breakdown of rocks and minerals at the Earth’s surface. It prepares materials for erosion, soil formation, and the development of landscapes. Weathering processes influence soil fertility, which is vital for agriculture and ecosystem health. Additionally, weathering plays a role in nutrient cycling and the formation of valuable mineral deposits, contributing to economic resources (Source: Soil Science Studies).

In summary, understanding earthquake waves and the concept of shadow zones enhances our knowledge of Earth’s interior, while weathering is essential for sustaining life and shaping landscapes.

Model Answer

Geomorphic processes shape the Earth’s surface through both internal and external forces. These processes are categorized as endogenic and exogenic, each with distinct characteristics.

Endogenic Processes

Location and Driving Forces

Endogenic processes occur within the Earth’s crust. They are driven by internal energy sources such as radioactivity, primordial heat, and tidal friction (Source: Geomorphology Texts).

Effects and Nature

These processes are primarily constructive, creating new landforms like mountains and volcanic islands through mechanisms such as diastrophism and volcanism. For example, earthquakes and volcanic eruptions exemplify endogenic activity, leading to significant geological changes (Source: Geoscience Literature).

Exogenic Processes

Location and Driving Forces

In contrast, exogenic processes take place on the Earth’s surface and are powered by external forces, particularly solar energy and atmospheric conditions (Source: Earth Science Resources).

Effects and Nature
Exogenic processes, including weathering, erosion, and mass wasting, are generally destructive. They break down and transport materials, reshaping landscapes through natural forces like wind, water, and ice (Source: Environmental Geology Studies).

Importance of Weathering

Weathering is a critical exogenic process involving the breakdown of rocks due to atmospheric and climatic conditions. It prepares materials for erosion and mass movements by fragmenting rocks into smaller pieces, which are essential for soil formation (Source: Soil Science Journals).

Additionally, weathering significantly influences biodiversity as it affects soil depth and quality, which in turn supports vegetation. The process also plays a vital role in altering landforms and enriching ore deposits of valuable minerals such as iron and copper, contributing to the economy (Source: Economic Geology Reports).

In summary, while endogenic processes build the Earth’s surface from within, exogenic processes, particularly weathering, are essential for breaking down materials and shaping the environment.