Natural Hazards and Disasters in India

India is among the most disaster-prone countries. About 58 percent of the land area is prone to moderate or high earthquakes, 12 percent to floods, 68 percent of cultivable area to drought, and 8 percent of the area to cyclones (approximate NDMA statements).

Earthquakes

• India is divided into four seismic zones: II, III, IV and V (BIS 2002; the lowest zone I was merged into II). Zone V is the most severe.
• Zone V: Kashmir valley, western and central Himalaya parts, north-east India, Kutch, Andaman and Nicobar.
• Zone IV: Delhi-NCR, Sikkim, north Bihar, parts of the Himalayan foothills, parts of J&K.
• Major earthquakes: Bhuj 2001 (M 7.7), Kashmir 2005 (M 7.6), Latur 1993, Sikkim 2011, Nepal 2015.

Floods

• Causes: heavy rain, river silt, cyclone surge, deforestation, encroachment.
• Flood-prone: Brahmaputra and Barak valleys, Kosi (called the Sorrow of Bihar), Ganga and Yamuna plains, Mahanadi delta, Godavari-Krishna deltas.
• Rashtriya Barh Ayog (1976) examined floods. Flood forecasting by CWC.

Cyclones

• Formed in the Bay of Bengal and the Arabian Sea in April-June and Oct-Dec. The Bay of Bengal has more cyclones, with Odisha, Andhra and West Bengal most affected.
• IMD categories use wind speed (depression, deep depression, cyclonic storm, severe cyclonic storm, very severe, extremely severe, super cyclonic storm).
• Recent names: Amphan (2020), Tauktae (2021), Yaas, Biparjoy (2023), Michaung (2023), Remal (2024), Dana (2024), Fengal (2024). The names come from a rotating list of the WMO/ESCAP panel of countries.
• Tsunami: 2004 Indian Ocean tsunami hit Tamil Nadu, Andaman and Nicobar; the Indian Tsunami Early Warning Centre at INCOIS, Hyderabad.

Droughts, landslides, other hazards

• Landslides: Himalaya, Western Ghats, Nilgiris, north-east. The Geological Survey of India prepares landslide maps.
• Droughts: types are meteorological, hydrological, agricultural.
• Heat wave: IMD declares when the maximum temperature reaches 40°C in the plains and is 4.5°C above normal.
• Cloudburst, avalanche (Siachen, Gulmarg), forest fires (Uttarakhand).

Disaster management framework