Types of Disasters — Set 1

Correct Answer: A. Natural and Man-made

Disasters are broadly classified into Natural and Man-made (anthropogenic) categories. Natural disasters include hydro-meteorological, geological, and biological events, while man-made disasters include industrial accidents, chemical spills, nuclear incidents, and conflicts. The Disaster Management Act 2005 uses this broad classification as the foundation for India's disaster risk management framework.

Correct Answer: B. Cyclone

Cyclone is a hydro-meteorological disaster caused by atmospheric and oceanic processes. Hydro-meteorological disasters include floods, cyclones, droughts, heatwaves, cold waves, hailstorms, and lightning events. The India Meteorological Department (IMD) monitors and issues warnings for all hydro-meteorological hazards in India.

Correct Answer: C. Earthquake

Earthquake is a geological disaster originating from processes within the Earth's crust and lithosphere. Geological disasters include earthquakes, landslides, avalanches, tsunamis, and volcanic eruptions. India has a high exposure to geological disasters due to its tectonic setting along the Himalayan collision zone and the peninsular shield.

Correct Answer: C. Epidemic

Epidemics are classified as biological disasters as they involve the rapid spread of infectious disease across a population. Biological disasters include epidemics, pandemics, pest infestations such as locusts, and outbreaks of plant or animal diseases. COVID-19 was declared a notified disaster under the Disaster Management Act 2005 in India, allowing special relief measures.

Correct Answer: B. Chemical/Industrial disaster

The Bhopal Gas Tragedy is classified as a chemical and industrial disaster caused by the accidental release of methyl isocyanate (MIC) gas from the Union Carbide plant. Man-made disasters include chemical, nuclear, industrial, and technological accidents resulting from human activities and failures. The Bhopal tragedy remains the world's worst industrial disaster and prompted global reforms in industrial safety standards.

Correct Answer: C. 4

IMD classifies droughts into 4 categories: Normal, Moderate, Severe, and Extreme based on rainfall deviation from the long-period average. A moderate drought corresponds to rainfall deficiency of 26–50%, severe drought is 51–75% deficiency, and extreme drought exceeds 75% deficiency. This classification helps in declaring drought conditions and mobilizing relief operations at the state and national level.

Correct Answer: C. 40°C

According to IMD, a heatwave on the plains is declared when the maximum temperature reaches at least 40°C. In addition to the absolute threshold, a heatwave is also declared when the departure from normal temperature is +4.5°C to +6.4°C (heatwave) or above +6.4°C (severe heatwave). Hill stations have a lower threshold of 30°C for heatwave declaration.

Correct Answer: C. +4.5°C to +6.4°C

IMD declares a heatwave when the temperature departure from normal is +4.5°C to +6.4°C, and a severe heatwave when the departure exceeds +6.4°C. The absolute criterion requires the maximum temperature to be at least 40°C on plains and 30°C for hill stations before applying the departure criterion. Heatwaves are most common in northwest and central India during April–June.

Correct Answer: C. 10°C

IMD declares a cold wave on the plains when the minimum temperature drops to 10°C or below. An additional criterion requires the departure from normal minimum temperature to be –4.5°C or lower for plains stations. Cold waves primarily affect northern India—particularly Punjab, Haryana, Delhi, UP, and Rajasthan—during December and January.

Correct Answer: C. Earthquake

Earthquakes are sudden-onset disasters that strike without warning and require immediate emergency response including search and rescue, medical aid, and evacuation. Sudden-onset disasters contrast with slow-onset disasters like drought, desertification, and sea-level rise which develop gradually over weeks, months, or years. The distinction between sudden-onset and slow-onset disasters determines the type of preparedness and response mechanisms needed.