Lancaster, UK:

As the heatwave begins to grip the UK and the heat health alert is in effect, people are looking for ways to keep cool and reduce the risk of heat stroke – the most severe form of hyperthermia, with a body temperature above 40°C.

Older adults, those with underlying health conditions and the very young are at greatest risk. Some of this arises because the young and elderly have less efficient body systems to dissipate heat away from the body.

Older people hold heat more than young people because their sweat glands don’t function as well and their hearts don’t circulate blood as efficiently, so less heat is lost from the skin.

Sweating is the most powerful way your body can remove heat. As sweat evaporates, it takes heat with it. In the heat, people can produce between a half to two litres of sweat per hour.

In temperatures where the air temp is above the body temperature, heat can be transferred from the air to the body, which produces an additional challenge in removing heat from the body.

Aside from sweating, the other major way we lose heat is vasodilation (a widening of the blood vessels) in peripheral tissues. In extreme heat, the skin can receive between six and eight litres of blood per minute to help carry heat away from central organs.

Much of how the body responds is aimed at moving heat away from the major organs and the central nervous system to keep their temperature at as close to 37°C as possible.

While sweating and vasodilation are effective, they are limited – especially when temperatures stay high for several days.

The best ways to reduce your temperature are ones that support the body’s existing mechanisms to remove heat.

Applying cold things to the body

Applying cold water or a cold damp sponge to the skin is effective in moving heat from the body. This is beneficial in people with limited mobility and older adults.

Those who are able, can take a cool shower or bath. Evidence suggests that water that is about 26 or 27°C is optimal. It is cool enough to take heat away from the body, but not cold enough to initiate shivering, which will generate heat. (Immersing in water that is too cold can also cause cold shock.)

Studies looking at the French heatwave of 2003 showed that cooling (using a mister, cool, or cold bath or shower, sponge bath, mechanical fan or air conditioner) may be beneficial and prevented heat-related deaths.

Ice or cool packs (a damp towel or cloth works just fine) can be applied to the body. The groin, armpit, neck, forehead, wrists and torso are all areas that have plenty of blood vessels close to the surface. The cooled blood can then return to the major organs to bring the core temperature down.

Ice or ice packs should be wrapped in a towel or something similar to avoid burning the skin. Cycling them on and off the body every ten minutes reduces the risk of injury.

Partial filling of hot water bottle and placing in the freezer, to use at bedtime, or placing pillowcases in a plastic bag and into the freezer to chill them for bedtime may also help at night.

Fans

A recent study has shown that fans can improve the body’s sweat evaporation, but not significantly enough to help reduce the core body temperature. And this becomes even less so when ambient temperatures rise above 33°C, or for older people and those with an impaired ability to sweat.

Hot and cold drinks

Evidence from performance athletes exercising in temperatures of 28°C showed that chilled fluids at fridge temperature were better at bringing down core temperatures than ice or temperature neutral liquids at 37°C.

Drinking hot beverages activates the body’s mechanism to cool, but this will remove much-needed fluid from the body if you haven’t drunk enough, so chilled drinks are probably best in this situation.

Shade

All of these things are more effective in a cooler shaded area to increase the temperature gradient between the body and the ambient temperature. If you try these in the sun, they’re likely to be less effective as the ambient air is warmer in the sun meaning there is less capacity to take heat away or it happens more slowly.

Overall, though, the evidence suggests (ice) water immersion is the most effective way to cool off – which at home is most easily done by immersing feet or hands in a cool bowl of water. Water immersion is how many animals in hot weather and climates reduce their body temperature by standing in water, so it’s a good technique for humans, too.

But if you’re unable to do this, evaporation (mist and fan) is the next most effective.

(Author:Adam Taylor, Professor and Director of the Clinical Anatomy Learning Centre, Lancaster University)

(Disclosure Statement:Adam Taylor does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment)

This article is republished from The Conversation under a Creative Commons license. Read the original article.
 

(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)

New Delhi:

Parts of Delhi today received heavy rain, bringing relief from the prevailing sultry conditions. Visuals shared by the news agency ANI showed heavy downpours in Munirka, Sarita Vihar, and other parts of the national capital with the India Meteorological Department (IMD) predicting more showers during the day.

#WATCH | Parts of Delhi receive heavy rainfall, bringing respite from heat.

Visuals from Sarita Vihar area. pic.twitter.com/OHkSOURVpB

— ANI (@ANI) June 27, 2024

“Light to moderate intensity rain and gusty winds with speed of 30-40 Km/h would occur over and adjoining areas of few places of Delhi during the next two hours,” the IMD said in a post on X at 7:30 AM.

The weather agency also predicted rain over Ghaziabad, Noida, and Gurugram.

Ghaziabad, Indirapuram, Chhapraula, Noida, Greater Noida, Faridabad) Panipat, Gohana, Gannaur (Haryana) Baraut, Bagpat, Meerut, Khekra, Modinagar, Pilakhua, Hapur, Gulaoti (U.P.) during next 2 hours. pic.twitter.com/qJ95g6K1SA

— RWFC New Delhi (@RWFC_ND) June 27, 2024

The much-awaited rain came after Delhi and other parts of north India witnessed weeks of intense spells of heatwave.

Delhi had been reeling from the sweltering heat and has recorded nine heatwave days in June so far against none in 2023 and 2022.

Earlier on Wednesday, the IMD predicted that Delhi’s maximum and minimum temperatures today would be around 38 degrees Celsius and 29 degrees Celsius, respectively.

The Safdarjung Observatory, the capital’s primary weather station, had recorded a temperature of 39 degrees Celsius on Wednesday, two notches above normal.

Monsoon Expected To Arrive In Delhi By End Of This Week

The monsoon could arrive in Delhi by the end of this week, a private weather agency forecast on Wednesday.

According to Mahesh Palawat of Skymet Weather Services, “The monsoon is expected to reach Delhi on June 29 or 30.” 

The IMD, however, has not shared any details of when the monsoon current is likely to enter the capital.

The monsoon current typically enters the city between June 27 and June 29. Last year, it arrived on June 26 while the first monsoon showers of 2022 were recorded on June 30.

Delhi’s meteorological and political climates seem to be in perfect sync this year. After the infernal heat and dust, the city is holding its breath. It’s like being transfixed by the cobra’s eyes. Everything is at a standstill. A pregnant pause. While the new parliament is in session, nothing significant has been achieved yet, either by the ruling party or the opposition. 

No, Rahul Gandhi becoming the Leader of the Opposition does not count as a significant event. This was along the predicted lines. Similarly, a drop in the mercury is not worth any mention. After twelve months of dealing with “the twelve hottest months in the history of the planet”, a promise of rain feels nothing more than trolling. 

Delhi Lives On

Delhi is not even complaining anymore. There is a new emergency heatstroke unit now at Ram Manohar Lohia Hospital where patients are being given ice baths to save their lives. Delhi has recorded at least 14 heatwave days, the highest in at least 14 years. There’s something deeply satisfying about such numerically synchronised stats, no matter what horrors they imply. Two hundred and seventy-five people have been recorded as fatal victims of the heatwave since mid-May in Delhi. The actual numbers are certainly much higher. Delhi is cranking up the air-conditioning. 

Also Read | 20 Dead In Delhi Heatwave, Centre Orders Hospitals To Prioritise Treatment

Even the chief minister’s continued incarceration is not making people’s – his voters and supporters’ – blood boil (the Aam Aadmi Party office at Rouse Avenue has more police around it than supporters). Delhi has a habit of slinking into complacency when ‘terrible’ becomes just a notch better and gets categorised as ‘bad’. Yes, it’s a hot day, but it’s not as bad as yesterday. Our collective memory of heat and dust is rather short. Or, it is too long. Going back centuries and millennia. 

“A Desert Like That Of Karbala”

“The city has become a desert, and now that the wells are gone and water is something rare and precious, it will be a desert like that of Karbala.” Battling a severe water crisis in summer, Delhi is thus described by one of the best-known Urdu poets of all time. Only, the year is 1859 and the poet is Mirza Ghalib. Such is the curse and charisma of Delhi, the more it changes, the more it stays the same. 

Also Read | Heatwave: Death Toll Climbs To 143 Across India

Delhi’s water crisis has worsened over the years. And so has its air. Unfortunately, nobody pays attention to these issues until there is a perfect time for it. In other words, whenever a convenient scapegoat is found. Air pollution, therefore, will only be talked about in the winter, just in time for Diwali and the harvest of rice. The moment the Haryana and Punjab farmers start to clear out their farms, Delhi complains of being choked. Facts and Air Quality Index (AQI) monitors be damned that throw up horrifying numbers all year long. The AQI reading for today, a pleasant day, is 300. Very pleasant indeed! Water is scarce today but in no time the city will be inundated, thanks to a swelling Yamuna and clogged or absent drains. 

Dysfunctional But Functioning

None of this is new. Delhi goes on. It has taken it upon itself to show Mumbai its place. What do you mean by the spirit of Mumbai? Even Delhi is willing to stay charred or flooded for days and still be ‘functional’. At least as functional as wealthy club-goers insisting on getting behind the wheel after a gallon of alcohol in their bodies.

What Delhi does not do is value accountability. And here is the catch. Once you start seeking accountability, you have to be accountable, too. Power outages, for example, can not be only owing to the faulty gear of the power companies or soaring demand etc. Surely, electricity theft and wastage at individual and institutional levels have a role to play in it. Similarly, air pollution may have something to do with the countless cars on the roads. It’s a big stereotype in the West that Delhi folk – the privileged lot that can afford foreign travel – are extremely poor walkers. Yes, despite boasting of one of the best public transport infrastructures in the country, Delhi relies on its private motor vehicle ownership. 

The Many Delhis

Delhi is second to none when it comes to flouting norms and laws in its quest to build and build some more. The city is perpetually under construction. According to a recent survey done by Ahmedabad’s Indian Institute of Public Health, more than 60% of construction workers suffer from heat stress during summer. Despite the Labour Ministry’s 2023 directives to construction companies for a change in working hours and humane work conditions, nothing has changed on the ground, thanks to the absence of strict enforcement. As long as the privileged in Delhi get their draft of cool air from their car ACs, they don’t care who drops dead next to their boiling vehicle. 

Delhi builds, Delhi sizzles, Delhi dies. Often, it’s not the same Delhi. 

(Nishtha Gautam is a Delhi-based author and academic.)

Disclaimer: These are the personal opinions of the author

New Delhi:

With Mumbai seeing the highest changes in the nighttime temperatures, India continues to suffer a severe heatwave, a new analysis on Friday showed climate change added nearly 50 to 80 nights each year where the temperature exceeded 25 degrees Celsius, with serious impacts on sleep and health.

Climate change is leading to a rise in nighttime warming, which is impacting sleep quality and human health in India and across the globe, said the analysis by Climate Central and Climate Trends.

Nighttime temperatures have increased even more rapidly than daytime temperatures as the world heats up due to climate change, primarily caused by burning fossil fuels like coal, oil, and gas.

As one of the countries most vulnerable to the impacts of the climate crisis, India has experienced a significant rise in minimum nighttime temperatures over the last decade due to climate change.

The national capital on June 18 experienced its warmest night in at least 12 years, with the mercury touching 35.2 degrees Celsius, says the India Meteorological Department. This is the city’s highest minimum temperature since 1969.

The analysis shows that nearly 50 to 80 days each year were added above this threshold by climate change in cities across Kerala, Karnataka, Maharashtra, Tamil Nadu, Punjab, Jammu and Kashmir, and Andhra Pradesh between 2018 and 2023.

Among the metro cities, Mumbai has seen the highest changes in the nighttime temperatures, with the city experiencing an additional 65 days of warmer nights due to global warming.

West Bengal and Assam are the regions that have been most impacted, with cities like Jalpaiguri, Guwahati, Silchar, Dibrugarh and Siliguri experiencing between 80 and 86 additional days each year above the 25 degrees threshold due to climate change, on average.

Several cities saw between 15 and 50 additional days where the minimum temperatures exceeded 25 degrees due to the influence of climate change, including Jaipur, with an additional 19 hot nights attributable to climate change.

Meanwhile, in both observations and in the counterfactual climate, the nighttime summer temperatures across India often exceed 20 degrees over the entire summer period.

The cities that had the largest number of days where the minimum temperature exceeded 20 degrees due to climate change are Gangtok, Darjeeling, Shimla, and Mysore, with an average of 54, 31, 30, and 26 days added by climate change, respectively.

Higher nighttime temperatures can cause physiological discomfort and impact human health by preventing body temperature from cooling off during the night, increasing mortality risks.

There is also a growing body of evidence that as nighttime temperatures rise, it is adversely affecting the quality and length of sleep.

Poor sleep adversely affects physical and mental health, cognitive functioning and even life expectancy. Hot nights can have disproportionate impacts on vulnerable groups, including the elderly and people, who do not have access to proper cooling mechanisms.

These findings come during a week that saw new records for nighttime heat in several Indian cities.

On June 19, Delhi shattered the all-time high minimum temperature record, with the mercury reaching 35.2 degrees overnight. Delhi recorded almost four numbers of additional nights over 25 degrees between 2018 and 2023, according to the Climate Central analysis.

On June 18, Alwar in Rajasthan had a minimum temperature of 37 degrees, the highest-ever nighttime temperature since records began in 1969.

Alwar experienced almost nine additional nights over 25 degrees that are attributable to climate change between 2018 and 2023.

In Uttar Pradesh, Lakhimpur Kheri, Shahjahanpur and Varanasi also witnessed their highest recorded minimum temperatures at 33 degrees, 33 and 33.6 degrees respectively this week.

Varanasi saw four additional nights over 25 degrees due to climate change from 2018 to 2023.

These increasingly frequent extreme nighttime temperatures are contributing to heat stress, exhaustion and heat-related deaths.

The current ongoing heatwave in India has been made hotter, frequent and more likely by climate change, according to scientific studies by World Weather Attribution and ClimaMeter.

Roxy Mathew Koll, Climate Scientist, Indian Institute of Tropical Meteorology, Pune, “The urban heat island effect is most visible in the nighttime temperatures. Cities turn into urban heat islands when buildings, roads, and other infrastructure absorb and re-emit heat, causing cities to be several degrees hotter than surrounding rural areas.”

“During the day, the sun’s rays reach as shortwave radiation and heat the earth’s surface. At night, the heat escapes as longwave radiation. While shortwave radiation can easily penetrate through and reach the surface, the longwave gets trapped easily by concrete and clouds.”

Aarti Khosla, Director, of Climate Trends, said, “Like day temperatures, night temperatures have also shown constant and steady rise over the last few years. Warm nights have been punishing this summer with several cities shattering five decades of records. Cities will bear the highest brunt which will get worse due to the urban heat island effect.”

“Several studies have already established that by the turn of the century, without very large reductions in fossil fuel burning, nighttime temperatures will not fall below 25 degrees in some places during hot weather impacting one’s ability to recover for the next day. If we do not act now, nights will continue to be hotter, longer and sleepless, especially for the vulnerable.”

(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)

Riyadh:

The death count from this year’s hajj has exceeded 1,000, an AFP tally said on Thursday, more than half of them unregistered worshippers who performed the pilgrimage in extreme heat in Saudi Arabia.

The new deaths reported Thursday included 58 from Egypt, according to an Arab diplomat who provided a breakdown showing that of 658 total dead from that country, 630 were unregistered.

All told around 10 countries have reported 1,081 deaths during the annual pilgrimage, one of the five pillars of Islam which all Muslims with the means must complete at least once.

The figures have come via official statements or from diplomats working on their countries’ responses.

The hajj, whose timing is determined by the lunar Islamic calendar, fell again this year during the oven-like Saudi summer.

The national meteorological centre reported a high of 51.8 degrees Celsius (125 degrees Fahrenheit) earlier this week at the Grand Mosque in Mecca.

According to a Saudi study published last month, temperatures in the area are rising 0.4 degrees Celsius each decade.

Each year tens of thousands of pilgrims attempt to perform the hajj through irregular channels as they cannot afford the often costly official permits.

Saudi authorities reported clearing hundreds of thousands of unregistered pilgrims from Mecca earlier this month, but it appears many still participated in the main rites which began last Friday.

This group was more vulnerable to the heat because, without official permits, they could not access air-conditioned spaces provided by Saudi authorities for the 1.8 million authorised pilgrims to cool down after hours of walking and praying outside.

“People were tired after being chased by security forces before Arafat day. They were exhausted,” one Arab diplomat told AFP on Thursday, referring to Saturday’s day-long outdoor prayers that marked the hajj’s climax.

The diplomat said the principal cause of death among Egyptian pilgrims was the heat, which triggered complications related to high blood pressure and other issues.

In addition to Egypt, fatalities have also been confirmed by Malaysia, Pakistan, India, Jordan, Indonesia, Iran, Senegal, Tunisia and Iraq’s autonomous Kurdistan region, though in many cases authorities have not specified the cause.

Friends and family members have been searching for pilgrims who are still missing.

On Wednesday they scoured hospitals and pleaded online for news, fearing the worst during the scorching temperatures.

Saudi Arabia has not provided information on fatalities, though it reported more than 2,700 cases of “heat exhaustion” on Sunday alone.

(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)

Kanpur:

In a worrying factor, several bats were found dead in the Nana Rao Park in Kanpur due to the intense heatwave that has gripped the region.

The carcasses were found in the park, where hundreds of bats live. Locals said they encountered bats falling from the trees, writhing in pain on the ground before succumbing to the heat.

With temperatures breaching the 45 degrees Celsius mark, locals added that bats were dying in large numbers in the park and the accumulation of carcasses resulted in a foul smell throughout the park.

Bats play an important role in habitats around the world and in India. Some tropical plants depend partly or wholly on certain bat species to pollinate their flowers or spread their seeds, while many bats help control insects by feeding on them and save farmers thousands of rupees in pest control chemicals.

Dr Anurag Singh, a veterinary officer at Kanpur Zoo, said bats are particularly susceptible to heat as they feel temperatures two degrees Celsius higher than humans.

“When the temperature in Kanpur hits 44 to 45 degrees Celsius, bats experience it as 47 to 48 degrees. Their suffering is compounded by the lack of accessible water sources, leading to heat strokes,” Dr Singh said.

He said that to prevent bats from dying, areas under trees should be kept moist and filled with water so that these animals get some relief from the relentless heat.

(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)

Jerusalem:

Diplomats on Tuesday said at least 550 pilgrims died during the hajj, underscoring the gruelling nature of the pilgrimage which again unfolded in scorching temperatures this year.

At least 323 of those who died were Egyptians, most of them succumbing to heat-related illnesses, two Arab diplomats coordinating their countries’ responses told AFP.

“All of them (the Egyptians) died because of heat” except for one who sustained fatal injuries during a minor crowd crush, one of the diplomats said, adding the total figure came from the hospital morgue in the Al-Muaisem neighbourhood of Mecca.

At least 60 Jordanians also died, the diplomats said, up from an official tally of 41 given earlier on Tuesday by Amman.

The new deaths bring the total reported so far by multiple countries to 577, according to an AFP tally.

The diplomats said the total at the morgue in Al-Muaisem, one of the biggest in Mecca, was 550.

The hajj is one of the five pillars of Islam and all Muslims with the means must complete it at least once.

The pilgrimage is increasingly affected by climate change, according to a Saudi study published last month that said temperatures in the area where rituals are performed were rising 0.4 degrees Celsius (0.72 degrees Fahrenheit) each decade.

Temperatures hit 51.8 degrees Celsius (125 Fahrenheit) at the Grand Mosque in Mecca on Monday, the Saudi national meteorology centre said.

– Heat stress –

Earlier on Tuesday, Egypt’s foreign ministry said Cairo was collaborating with Saudi authorities on search operations for Egyptians who had gone missing during the hajj.

While a ministry statement said “a certain number of deaths” had occurred, it did not specify whether Egyptians were among them.

Saudi authorities have reported treating more than 2,000 pilgrims suffering from heat stress but have not updated that figure since Sunday and have not provided information on fatalities.

At least 240 pilgrims were reported dead by various countries last year, most of them Indonesians.

AFP journalists in Mina, outside Mecca, on Monday saw pilgrims pouring bottles of water over their heads as volunteers handed out cold drinks and fast-melting chocolate ice cream to help them keep cool.

Saudi officials had advised pilgrims to use umbrellas, drink plenty of water and avoid exposure to the sun during the hottest hours of the day.

But many of the hajj rituals, including the prayers on Mount Arafat which took place on Saturday, involve being outdoors for hours in the daytime.

Some pilgrims described seeing motionless bodies on the roadside and ambulance services that appeared overwhelmed at times.

Around 1.8 million pilgrims took part in the hajj this year, 1.6 million of them from abroad, according to Saudi authorities.

– Unregistered pilgrims –

Each year tens of thousands of pilgrims attempt to perform the hajj through irregular channels as they cannot afford the often costly procedures for official hajj visas.

This places these off-the-books pilgrims at risk as they cannot access air-conditioned facilities provided by Saudi authorities along the hajj route.

One of the diplomats who spoke to AFP on Tuesday said that the Egyptian death count was “absolutely” boosted by a large number of unregistered Egyptian pilgrims.

“Irregular pilgrims caused great chaos in the Egyptian pilgrims’ camps, causing the collapse of services,” said an Egyptian official supervising the country’s hajj mission.

“The pilgrims went without food, water, or air conditioning for a long time.”

They died “from the heat because most people had no place” to take shelter.

Earlier this month, Saudi officials said they had cleared hundreds of thousands of unregistered pilgrims from Mecca ahead of the hajj.

Other countries to report deaths during the hajj this year include Indonesia, Iran and Senegal.

Most countries have not specified how many deaths were heat-related.

Saudi Health Minister Fahd bin Abdul Rahman Al-Jalajel said on Tuesday that health plans for the hajj had “been successfully carried out”, preventing major outbreaks of disease and other public health threats, the official Saudi Press Agency reported.

Health officials “provided virtual consultations to over 5,800 pilgrims, primarily for heat-related illnesses, enabling prompt intervention and mitigating the potential for a surge in cases,” SPA said.

(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)

An American tourist has been found dead on a beach on a remote Greek island after going missing amid a spate of disappearances. According to the Guardian, the body of the man was found Sunday on a rocky, fairly remote beach on the island of Mathraki by another tourist. 

The man, whose identity has not yet been released, disappeared on the island after last being seen on June 11, when temperatures reached as high as 104 degrees Fahrenheit. The man was staying with a Greek-American friend on the island before he vanished, according to investigators. He was last seen alive at a tavern on Tuesday with two female tourists who later left the island further details about the victim, including a name or hometown, were immediately available.

Mathraki has an estimated population of just 100 people and is located west of the island of Corfu, as per Sky News.

It is the latest in a string of recent cases in which tourists in the Greek islands have died or gone missing. Before this, a 74-year-old Dutch tourist was found by a fire department drone on Saturday lying face down in a ravine about 300 meters from the spot where he was last observed last Sunday. Officials said observers reported the Dutch tourist having some difficulty hiking in the triple-digit heat that has enveloped the islands.

Dr Michael Mosley, a noted British TV anchor and author, was also found dead last Sunday on the island of Symi. His body was found in a rocky area, and investigators concluded that he died of natural causes the day he went missing.

One American and two other French tourists have also recently been reported missing. It is believed that they all set out on hikes in unusually high temperatures.

Notably, Greece is one of the most hard-hit countries by global warming in Europe, with rising temperatures fuelling deadly fires and erratic rains in recent years. Last Thursday, the famous Acropolis, and other nearby tourist attractions were closed as winds from North Africa pushed temperatures towards 43 degrees Celsius (109 degrees Fahrenheit). Many primary schools and nurseries nationwide were also closed to protect students from the heat.

Scientists warn that summer temperatures there could rise by an average of 2 degrees by 2050. Athens mayor Haris Doukas has tried to create more shade by planting 2000 trees.

The story so far: At least five people in Bihar’s Aurangabad city reportedly died on Thursday due to a sunstroke, news agency Reuters reported. Parts of north and central India continued to reel under a severe heatwave on Thursday, even as the India Meteorological Department (IMD) predicted a gradual fall in temperature over the next five days. On Wednesday, an automatic weather station in Delhi recorded a maximum temperature of 52.9 degrees Celsius, the highest temperature on record in the capital. The IMD, however, said that this could be due to “an error in sensor or local factors”, since the recorded temperature was an outlier. The IMD is said that it is examining the data and sensors.

Ten more people were reported dead government hospital in Odisha’s Rourkela region on Thursday due to the heat. A 40-year-old labourer in Delhi died due to a heatstroke (a condition in which the body temperature increases beyond 40 degrees C) on Thursday, The Indian Express reported. Despite these reports, it must be noted that heat-related deaths are widely underreported.

What does IMD’s latest report say?

As per the IMD report released Friday afternoon, maximum temperatures in northwest and central India are predicted to fall gradually by 2-3 degrees C in the next three days.

Maximum temperatures on Thursday in most parts of Delhi, Haryana, and Chandigarh, as well as large parts of Rajasthan, and isolated pockets over eastern Madhya Pradesh, Uttar Pradesh, Bihar, Jharkhand, and Odisha were recorded in the range of 45-48 degrees C.

Parts of western Madhya Pradesh, Chhattisgarh, and coastal Andhra Pradesh, and isolated pockets over Gujarat, Telangana, and Rayalaseema recorded maximum temperatures in the range of 42-45 degrees C.

How do heatwaves arise?

Some experts believe that post El Niño warming has contributed to higher-than-usual temperatures in north India this year.

El Niño and La Niña are atmospheric patterns that influence the warming and the cooling of sea surface temperatures in the Central and Equatorial Pacific. The two opposing patterns occur in an irregular cycle called the El Niño Southern Oscillation (ENSO) cycle, with a neutral period in between.

In March 2024, the World Meteorological Organisation (WMO) announced that even though the 2023-24 El Niño, which peaked as one of the strongest on record and has declined since, will continue to impact climate for the coming months. This exacerbates the heat captured by anthropogenically produced greenhouse gases, causing higher temperatures.

The IMD, in its May bulletin, said that weak El Niño conditions are currently observed over equatorial Pacific and are likely to weaken further and convert into ENSO neutral (the Australian Bureau of Meteorology had already announced on April 16 that the ENSO cycle is now in neutral).

A study published in 2016 had predicted that if El Niño activity increases in the future, heatwaves in India were likely to intensify.

During El Niño, surface temperatures in the equatorial Pacific rise, and trade winds — east-west winds that blow near the Equator — weaken. Normally, easterly trade winds blow from the Americas towards Asia. Due to El Niño, they falter and change direction to turn into westerlies.

ENSO, however, does not cause extreme heat in isolation. Teleconnections, which are the relationships between global weather and wind patterns, impact each other. The Walker circulation, which involves the trade winds that blow from east to west along the Equator, are affected by ENSO due to teleconnections.

El Niño is associated with a shift in Walker circulation, causing a large-scale redistribution of heat and moisture. Heat redistribution on the surface impacts airflows above the ocean. It is known that El Niño diminishes Indian monsoon since the weakened Walker circulation disrupts the flow of moist air from the Indian Ocean towards the Indian subcontinent, reducing the moisture available in the winds, hence creating drier conditions.

El Niño also creates high-pressure areas over the Indian subcontinent, which suppress cloud formation and precipitation. The absence of clouds is also contributing to the current heatwave in north and central India.

What’s the cause of North India’s heat?

Delhi and most parts of north and central India that are currently under a heatwave spell, are far from the influence of oceans that can regulate temperatures and air moisture. Continental air, which is a large volume of dry air over a land mass, greatly affects the weather in Delhi because of its inland location. Tropical air masses that originate in the Thar Desert and other hotter, drier regions to the west and northwest of India bring increased heat to Delhi and surrounding areas, contributing to heatwave conditions.

Another important factor exacerbating heatwave conditions in India is loss of tree cover. “The vast expanses of open areas with very little or no trees increase the impact of direct sunlight,” Indu K. Murthy, head of Climate, Environment and Sustainability at CSTEP, told The Hindu. According to the Global Forest Watch, India lost 2.33 million hectare of tree cover from 2001 to 2023, which is equivalent to a 6% decrease in tree cover since 2000, and 1.20 billion tonnes of CO₂e emissions.

In urban areas, the urban heat island (UHI) effect is also at play and contributes to hot conditions. In the UHI effect, urban areas are significantly warmer than their surroundings because building materials like concrete, asphalt, bricks, etc. have higher thermal inertia and absorb and retain more heat than natural landscapes, causing a localised increase in temperature. Densely packed buildings lack proper airflow that allows for cooling.

A study published in Nature journal on May 15, 2024 found that urbanisation alone has led to a 60% enhancement in warming in Indian cities. The UHI effect contributes to global warming as it is associated with an increased demand for energy which leads to a higher production of greenhouse gases. The UHI effect can also impact climate factors other than heat, like rainfall, pollution, etc.

A report by the Centre for Science and Environment, published in May 2024, found that cities are not cooling down at night at the same rate that they used to, not giving people a chance to recover from the daytime heat. “Hot nights are as dangerous as midday peak temperatures,” the study noted. In Delhi, nights are slightly cooler by just 11.2 degrees C, which is 9% down from 2001-2010.

The CSE report also said that the UHI effect is stronger at night than daytime in Delhi.

Is the Delhi Heat Action Plan enough?

Delhi has a Heat Action Plan in place for 2024-2025, but at this stage, it is more like a set of guidelines.

“While the Heat Action Plan of Delhi is a fantastic first step, what is needed is building of capacity across the ecosystem, and the access to funds and facilities that could be utilised without too much bureaucratic hurdles. More importantly, a more disaggregated approach to looking at the problem, applying the demographic and socio-economic lens is a must, as many of the generic solutions may not really serve the under-privileged lower economic strata of people,” Dr. Murthy from CSTEP said.

The Hindu tried reaching out to the Delhi Disaster Management Authority to inquire about the steps it has undertaken to implement the Heat Action Plan, but did not receive a response.

Aditya Valiathan Pillai, a fellow at Sustainable Futures Collaborative, said if we don’t start now, we won’t be able to beat the heat in 10 years. “Delhi has to play catch-up over the next couple of years, as implementing the ideas mentioned in the HAP takes time. My concern with this plan is it doesn’t talk about financing. [The government] needs to figure out how it is going to finance this long list of solutions it has proposed,” Mr. Pillai said.

He added that the plan needs to be grounded in some legal structure for it to “have weight within the bureaucracy and the government”.

Rourkela:

 Ten people died of suspected heatstroke in Odisha’s Rourkela city on Thursday, as the mercury shot up in most parts of the eastern state, officials said.

The director-in-charge (DIC) of Rourkela Government Hospital (RGH), Dr Sudharani Pradhan, said the deaths occurred within a span of six hours from 2 pm onwards.

“Eight people were dead by the time they reached the hospital, while the rest died while undergoing treatment here. This was likely due to the intense heatwave,” she said.

“The body temperatures were around 103-104 degrees Fahrenheit, which is very high given the weather conditions. This could be the possible reason behind the deaths. The history could not be studied as they arrive dead,” she said.

A few more people were undergoing treatment.

“At this moment the real cause is not known. It could be ascertained tomorrow after the post-mortem examination,” said Ms Pradhan.

The Director of Public Health, U K Sahoo confirmed the deaths of 10 people and said, “Ten people have died, but identities of all of them are yet to be ascertained.” Meanwhile, heat wave conditions prevailed across Odisha, particularly the western region, as temperatures soared to more than 44 degrees C in 12 places on Thursday.

The IMD in its evening bulletin said as many as 19 places in the state recorded a maximum temperature of more than 40 degrees C.

Heatwave conditions prevailed in Jharsuguda, Bolangir, Bargarh, Sambalpur, Sonepur, Malkangiri, Sundargarh, Nuapada and Kandhamal districts, it said.

Jharsuguda was the hottest in the state as the maximum temperature in the western Odisha district zoomed to 47 deg C.

Jharsuguda was followed by Titlagarh at 46.5 deg C, Bargarh at 46.3 deg C and Sambalpur at 46.2 deg C.

The mercury level rose to 45.6 deg C at Sonepur, while Malkangiri recorded 45.6 deg C, Bhawanipatna 45.5 deg C, Balangir 45.3 deg C and Hirakud 45.2 deg C.

(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)