MCQs on Natural Hazards and Disasters for UPSC and State PSC exams

Hazard is natural phenomenon; disaster occurs when hazard exceeds coping capacity causing loss of life and property.

Located on active plate boundary, monsoon variability, long coastline, Himalayan fragility increase risk.

Indian plate moves north 5 cm/yr, creates stress along Himalayan front and faults, causing frequent quakes.

BIS seismic zonation: Zone V (most active) includes NE, J&K, Himachal, Uttarakhand; Zone IV covers Indo-Gangetic plain.

Bhuj killed >13,000, in Zone V Kutch, intraplate earthquake due to reactivated fault.

Magnitude 6.4 in Deccan plateau, showed peninsular faults are active, killed 10,000.

Sudden vertical displacement of ocean floor generates long-wavelength waves traveling at 800 km/h.

Subduction of Indian plate under Burma plate, waves hit Tamil Nadu, Andaman, killed 2.3 lakh globally.

Indian Tsunami Early Warning Centre established 2007 at INCOIS, monitors seismic and sea level data.

Bay is warmer, low shear, funnel shape, causes more frequent and intense cyclones.

Pre-monsoon and post-monsoon due to warm SST >26.5°C and low vertical wind shear.

Extremely severe cyclonic storm, landfall Puri, effective evacuation reduced deaths.

Rare intense Arabian Sea cyclone in May, caused damage in Mumbai, Gujarat.

Low pressure and strong onshore winds pile water, causes coastal flooding, main killer in cyclones.

Brahmaputra, Ganga, Kosi, Mahanadi basins flood annually, 40 million ha flood-prone.

Carries huge silt from Himalayas, avulses westward, breaches embankments.

Narrow valley, high discharge, sediment raises river bed.

Unplanned urbanization reduces infiltration, storm drains clogged.

Steep slopes, heavy rain, deforestation, road cutting, seismic activity trigger mass movement.

2024 Wayanad landslides killed hundreds due to heavy rain on fragile slopes.

Snow accumulation on steep slopes, triggered by temperature rise or tremors.

Meteorological drought; agricultural drought when soil moisture insufficient for crops.

Progressive impacts from rainfall deficit to water scarcity and ecosystem stress.

Receive <75 cm rain, high variability, frequent crop failure.

Caused by overgrazing, deforestation, wind erosion, climate change.

Temperature >45°C, IMD declares heat wave when departure >4.5°C from normal.

Temperature <4°C in plains, due to western disturbances and snowfall in Himalayas.

India has highest lightning deaths globally, >2,500 annually, due to convective storms.

Uttarakhand, Himachal, MP, Odisha face fires due to dry litter and human activity.

Causes flash floods and landslides, common in Himalayas – e.g., Leh 2010, Uttarakhand 2013.

Chorabari Lake breach, 6,000 deaths, combination of hydro-meteorological hazard.

Climate warming melts glaciers, lakes expand, risk in Himalayas – e.g., Sikkim 2023 Teesta flood.

Sea level rise, cyclones, sand mining cause shoreline retreat, 33% coastline eroding.

IPCC projects 0.3-1 m rise by 2100, submergence of low-lying islands like Lakshadweep.

COVID-19 pandemic 2020, locust invasion 2020 in Rajasthan-Gujarat affected crops.

Bhopal 1984 methyl isocyanate leak killed >3,000, worst industrial disaster.

Apex body for disaster management, chaired by PM, coordinates preparedness and response.

National Disaster Response Force, 16 battalions, specialized for rescue operations.

UN framework adopted by India, focuses on prevention, preparedness, Build Back Better.

Integrated systems use satellites, Doppler radars, sensors.

Villagers trained in first aid, evacuation, reduces vulnerability.

BIS codes IS 1893, IS 4326 guide seismic design in Zones IV-V.

Structural and non-structural measures, e.g., DVC dams on Damodar.

Integrated approach improves resilience.

After 1999 Super Cyclone, Odisha built 800+ shelters, reduced deaths in Fani.

Sundarbans mangroves absorb wave energy, protect hinterland.

Risk increases with hazard and vulnerability, decreases with coping capacity.

Socio-economic conditions amplify disaster impact.

Warming increases extreme rainfall, cyclones, heat waves, GLOFs.

NDMA guidelines mandate school safety, regular drills, hazard maps, training teachers and students reduces casualties during earthquakes and fires.