From UPSC perspective, the following things are important :
Prelims level: Heatwaves, State-specific Disasters
Why in the News?
- The Tamil Nadu government has officially declared heatwaves a State-specific disaster.
- It announced an ex-gratia payment of ₹4 lakh for families of individuals who die from heat-related causes, including those involved in relief operations.
Key Details of the Declaration
Note:
|
About Heatwaves:
Details | |
Definition | A heatwave is a prolonged period of excessively hot weather, relative to the usual climate of a region. |
Occurrence | Typically occurs in India between March and June. |
Declaration by IMD |
|
Formation | • High-Pressure Systems: Develop when high pressure settles over a region for days or weeks. • Air Sinking: Forces air to sink, warming and drying it. • Increased Radiation: Fewer clouds lead to higher surface temperatures. • Surface Winds: Warm air from lower latitudes or continental winds intensify heat. |
Criteria for Declaring a Heatwave | At least two stations in a meteorological subdivision must meet one of the following criteria for two consecutive days (declared on the second day): Based on Departure from Normal: – Heat Wave: Temperature departure of 4.5°C to 6.4°C above normal. – Severe Heat Wave: Temperature departure of >6.4°C above normal. Based on Actual Maximum Temperature (plains only): – Heat Wave: Maximum temperature reaches 45°C or higher. – Severe Heat Wave: Maximum temperature reaches 47°C or higher. |
Duration | Typically lasts a minimum of four days but can extend to seven or ten days. Longest Recorded Spell: May 2015, lasting from 18 to 31 May. |
Impact of Heatwaves | • Heat Strokes: Increased risk, especially for the elderly and those with chronic illnesses. • Increased Healthcare Costs: Higher hospital visits and death rates from related illnesses. • Reduced Productivity: Extreme heat affects the output of over 1 billion workers. • Risk of Wildfires: Heat domes can lead to wildfires. • Effect on Vegetation: Prolonged heat damages crops and leads to droughts. • Increased Energy Demands: Higher electricity usage for cooling, driving up rates. |
PYQ:[2013] Bring out the causes for the formation of heat islands in the urban habitat of the world. [2013] The annual range of temperature in the interior of the continents is high as compared to coastal areas. What is / are the reason / reasons? 1. Thermal difference between land and water 2. Variation in altitude between continents and oceans 3. Presence of strong winds in the interior 4. Heavy rains in the interior as compared to coasts Select the correct answer using the codes given below. (a) 1 only (b) 1 and 2 only (c) 2 and 3 only (d) 1, 2, 3 and 4 |
Get an IAS/IPS ranker as your 1: 1 personal mentor for UPSC 2024