Wet-bulb temperature of 32-35º C can be lethal as Chennai humidity rises
GS3Economy · S&T · Environment · Security· Climate change & international agreements· Prelims·
Climate change and thermal stress: a GS3 and Science & Technology case study on humidity and heat.
Why in news
The rising humidity in Chennai has led to concerns over lethal wet-bulb temperatures, where high moisture prevents sweat evaporation and causes dangerous heat accumulation.
Background
A wet-bulb temperature of 32-35°C is identified as potentially lethal for humans.
Facts for Prelims
- FactChennai recorded 70% absolute humidity and 60% relative humidity at 32°C on April 23.
- S&TWet-bulb temperature is a measure of the hottest temperature that upholds the body's ability to evaporate sweat.
- FactA wet-bulb temperature of 32-35°C is considered lethal due to the inability of the human body to cool itself.
Prelims practice question
What was the recorded absolute humidity in Chennai at 32°C on April 23?
- (a)85%
- (b)70%
- (c)90%
- (d)80%
Show answer
Answer: (b) 70% — The note states that Chennai recorded 70% absolute humidity and 60% relative humidity at 32°C.
For Mains
Q. Discuss how rising humidity levels and wet-bulb temperatures pose a significant threat to public health in coastal Indian cities amidst the escalating climate crisis.
Dimensions to cover in your answer
- Physiological threshold: Human body's inability to thermoregulate when sweat evaporation is inhibited by high humidity
- Urban heat island effect: Interaction between coastal humidity and urban infrastructure exacerbating heat stress
- Climate adaptation gap: Lack of specialized heat-action plans for high-humidity coastal environments
Keywords: wet-bulb temperature · thermoregulation · climate crisis · heatwave · humidity · public health
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This note is generated automatically from SatyaDheesh's news feed and mapped to the UPSC CSE syllabus. Check facts against the original report or PIB before using them in an answer.