Disaster Management > Disasters > Disaster risk reduction
Why in news?
- Many areas of India are likely to experience severe to very severe heatwave conditions.
What is a heatwave and when is it declared?
- Heatwaves occur over India between March and June.
- Meteorologists declare a heatwave event when the maximum (day) temperature for a location in the plains crosses 40 degrees Celsius.
- Over the hills, the threshold temperature is 30 degrees Celsius.
- When the day temperature jumps by 4 to 5 degrees above the normal maximum temperature of a location, it is declared as a heatwave.
- Alternatively, any location where maximum temperature crosses 45 degrees or shows a departure of over 6 degrees from normal, it is a severe heatwave condition.
How long can a heatwave spell last?
- A heatwave spell generally lasts for a minimum of four days but can extend up to seven or ten days.
- Heatwaves are common over the Core Heatwave Zone (CHZ) — Rajasthan, Punjab, Haryana, Chandigarh, Delhi, West Madhya Pradesh, Uttar Pradesh, Chhattisgarh, Orissa, Vidarbha in Maharashtra, parts of Gangetic West Bengal, Coastal Andhra Pradesh and Telangana, as categorised by India Meteorological Department.
- Factors like Western Disturbances which cause rainfall over northern India can reduce the impact of heat waves.
Consider the following statements regarding Heat waves:
1.In India, heat waves are declared when the maximum temperature jumps by 4 to 5 degrees above normal.
2.Heatwaves occur in India between March and June
Choose the correct statements from the codes given below:
(c)Both 1 and 2
(d)Neither 1 nor 2
Answer to the Prelims Question