Physical Geography is a core foundation subject for UPSC Prelims. It not only contributes directly to Geography questions but also supports Environment, Ecology, and Disaster Management. The focus should be on conceptual clarity, interlinkages, and application-based understanding.

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Structure of the Earth

Prepare the following fundamental concepts:

Interior of the Earth

• Layers: Crust, Mantle, Core
• Differences between continental and oceanic crust
• Density and compositional variations

Evidence for Earth’s Interior

• Role of seismic waves in understanding Earth’s structure

Types of Seismic Waves

• Primary (P-waves) – travel through solids and liquids
• Secondary (S-waves) – travel only through solids
• Surface waves – most destructive

Shadow Zones

• Absence of P and S waves in certain areas
• Helps determine the nature of Earth’s core

Rocks and Rock Cycle

• Types of rocks: Igneous, Sedimentary, Metamorphic
• Rock cycle processes: formation, transformation, recycling

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Geomorphology (Landforms)

Forces Shaping the Earth

• Endogenic forces (internal)
• Exogenic forces (external)

Theories to Study

• Plate Tectonic Theory
• Continental Drift Theory
• Sea-floor Spreading

Mountains and Landforms

• Fold mountains
• Block mountains
• Volcanic mountains

Earthquakes

• Causes and global distribution patterns

Volcanoes

• Shield volcanoes
• Composite volcanoes

Weathering

• Mechanical weathering
• Chemical weathering
• Biological weathering

Erosion and Deposition

• River landforms (valleys, deltas)
• Wind landforms (dunes, loess)
• Glacial landforms (moraines, cirques)

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Climatology

Structure of Atmosphere

• Layers: Troposphere, Stratosphere, Mesosphere, Thermosphere

Heat Budget and Insolation

• Incoming solar radiation
• Distribution of temperature across latitudes

Pressure and Wind Systems

• Pressure belts of Earth
• Wind systems and their causes

Planetary Winds

• Trade winds
• Westerlies
• Polar easterlies

Monsoon Mechanism

• Indian monsoon system
• Role of land-sea contrast, ITCZ, and winds

Jet Streams

• High-speed upper atmospheric winds
• Influence on weather and monsoon

Cyclones

• Tropical cyclones vs temperate cyclones
• Formation and characteristics

Climate Phenomena

• El Niño and La Niña
• Impact on global weather

Climate Change

• Global warming
• Causes and consequences

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Oceanography

Ocean Relief

• Continental shelf
• Continental slope
• Abyssal plains

Ocean Currents

• Warm currents
• Cold currents
• Impact on climate

Coriolis Effect

• Deflection of winds and currents due to Earth’s rotation

Tides

• Spring tides
• Neap tides

Salinity and Temperature

• Distribution patterns in oceans

Ocean Processes

• Upwelling and downwelling

Marine Resources

• Fisheries
• Minerals
• Energy resources

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