"Report Projects Rising Heat-Related Deaths in India Amid El Nino"
El Niño-Southern Oscillation (ENSO)
periodic warming of equatorial Pacific sea-surface temperatures that disrupts global weather patterns including the Indian monsoon.
Niño 3.4 Index
measure of sea-surface temperature anomaly in the central-eastern Pacific used to declare and track El Niño events.
El Niño is the periodic warming of sea-surface temperatures in the central and eastern equatorial Pacific Ocean. It is one phase of the broader El Niño-Southern Oscillation (ENSO) cycle. Under normal conditions, trade winds push warm surface water westward toward Asia and Australia. During El Niño, these winds weaken, the warm pool shifts eastward, and Pacific sea-surface temperatures rise. The World Meteorological Organization (WMO) tracks this using the Niño 3.4 Index, which measures sea-surface temperature anomaly in a defined stretch of the central-eastern Pacific. An anomaly above +0.5°C triggers an El Niño declaration. A related system, the Indian Ocean Dipole (IOD), measures the temperature difference between the western and eastern Indian Ocean. A positive IOD can offset El Niño's drying effect on the Indian monsoon, while a negative IOD can worsen it.
El Niño's most direct effect on India is a weakening of the southwest monsoon. This raises temperatures and reduces the cooling relief that rainfall normally provides. India's institutional response to heat has grown mainly through Heat Action Plans (HAPs), city and state-level frameworks that trigger early warnings, hospital preparedness, and public cooling measures once temperature thresholds are crossed. Ahmedabad's HAP, launched in 2013, was the first in South Asia. The National Disaster Management Authority (NDMA) later encouraged other states to adopt similar plans. Despite this, heat remains under-recognised as a disaster category. Heat deaths are rarely certified as such because a heat-triggered cardiac or respiratory failure is usually recorded under that immediate medical cause. Researchers therefore rely on excess mortality, the statistical gap between observed deaths and historically expected deaths, to estimate the true toll.
The current El Niño episode is being described as a Super El Niño. Pacific sea-surface temperature anomalies have already risen to around +2.6°C to +3°C above normal in the central-eastern Pacific and are projected to reach +4°C. This would exceed any level reconstructed from coral-core records over the past thousand years. The intensity matters because heat becomes deadly not just from air temperature alone. The wet-bulb temperature, which accounts for both heat and humidity together, is the real measure of survivability. Once wet-bulb temperature crosses approximately 35°C, sweating can no longer cool the body effectively. Prolonged exposure above this threshold becomes fatal even for healthy adults. A prior World Bank assessment had already flagged India as among the first places where wet-bulb temperatures could routinely cross this threshold.
To project heat deaths, the University of Chicago's Climate Impact Lab built separate mortality-temperature relationships for over 24,000 regions worldwide. …
The World Bank warned that India could become one of the first places where wet-bulb temperatures routinely exceed 35°C. Which of the following statements best reflect(s) the implication of the above-said report?
I.Peninsular India will most likely suffer from flooding, tropical cyclones and droughts.
II.The survival of animals including humans will be affected as shedding of their body heat through perspiration becomes difficult.
Select the correct answer using the code given below.
'Climate change' is a global problem. How India will be affected by climate change? How Himalayan and coastal states of India will be affected by climate change?
The physiological limit beyond which the human body cannot cool itself through perspiration is best described by which of the following?
Consider the following statements regarding El Niño:
1.El Niño refers to anomalous cooling of the equatorial Pacific Ocean.
2.El Niño years are typically associated with a weaker Indian summer monsoon.
Which of the statements given above is/are correct?
As per the World Meteorological Organization, a heat wave is declared when maximum temperature exceeds the historical average by at least how many degrees Celsius, for how many consecutive days?
Match the following heat-related concepts with their correct description:
List I:
A.Excess mortality
B.Wet-bulb temperature
C.Heat Action Plan
D.El Niño
List II:
1.City/state framework triggering early warnings on crossing heat thresholds
2.Gap between observed and statistically expected deaths
3.Anomalous warming of the equatorial Pacific Ocean
4.Combined heat-humidity measure of the body's cooling limit
Select the correct answer using the code below:
Which city launched India's first Heat Action Plan, later used as a model for other cities and states?
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