Physical Geography: Earthquakes to Glaciers

What the official syllabus says

UPPCS Main Examination, General Studies I.

Salient features of Physical Geography: Earthquake, Tsunami, Volcanic activity, Cyclone, Ocean Currents, winds and glaciers.

Topics in detail

The line lists seven phenomena. For each, know the process behind it, where it occurs in the world and in India, and its effects on people.

Earth's interior and plate tectonics

• Crust, mantle and core; continental drift (Wegener), sea-floor spreading, plate tectonics
• Plate boundaries: divergent, convergent, transform; the collision that raised the Himalaya

Earthquakes

• Focus and epicentre; P, S and surface waves; magnitude and intensity scales
• World distribution: the Pacific Ring of Fire, the Alpine-Himalayan belt, mid-ocean ridges
• Seismic zoning of India by the Bureau of Indian Standards; major Indian earthquakes (Bhuj 2001, Kashmir 2005)
• Preparedness: earthquake-resistant building codes, the National Disaster Management Authority

Tsunami

• Causes: undersea earthquakes, landslides, volcanic eruptions
• The Indian Ocean tsunami of 26 December 2004
• Indian Tsunami Early Warning Centre at INCOIS, Hyderabad

Volcanic activity

• Types of volcanoes (shield, composite, caldera) and of eruptions; volcanic landforms
• World distribution; the Ring of Fire
• India: Barren Island (active) and Narcondam (dormant) in the Andaman Sea; the Deccan Traps as ancient lava flows

Cyclones

• Tropical cyclones: conditions for formation (warm sea surface, Coriolis force, low wind shear), structure (eye, eyewall)
• Names in different oceans: hurricanes, typhoons, cyclones; naming in the north Indian Ocean
• Bay of Bengal and Arabian Sea cyclones; coastal vulnerability; early warning by the India Meteorological Department
• Temperate (extra-tropical) cyclones and western disturbances

Ocean currents

• Causes: planetary winds, temperature and salinity differences, the Coriolis force, the shape of coasts
• Warm and cold currents: Gulf Stream, Kuroshio, Labrador, California, Humboldt (Peru), Canary, Benguela
• Seasonal reversal of currents in the north Indian Ocean with the monsoon
• El Nino, La Nina and the Indian Ocean Dipole and their link with the Indian monsoon

Winds

• Pressure belts and planetary winds: trade winds, westerlies, polar easterlies
• Monsoon winds and theories of the monsoon; jet streams
• Local winds: loo, nor'westers (kalbaisakhi), mango showers; foehn, chinook, sirocco, mistral

Glaciers

• Types: continental ice sheets and valley glaciers
• Glacial landforms: cirque, arete, horn, U-shaped valley, moraines, drumlins, eskers
• Himalayan glaciers (Siachen, Gangotri) as sources of rivers; glacial retreat and glacial lake outburst floods

Overlaps

Disaster management is in General Studies III; physical geography is also tested in the Prelims General Studies Paper I.