The early onset of extreme heat, echoing patterns seen in 2022, signals a worrying shift in climate trends and raises urgent concerns for public health, agriculture, and energy infrastructure across North India

North India is experiencing a severe heatwave much sooner than anticipated this year. On Monday, 7th April, Delhi recorded its first heatwave of the season, with the temperature at the Safdarjung Observatory reaching 40.2°C. The India Meteorological Department (IMD) has released a yellow alert for the national capital and recommended that residents take essential precautions. Different areas of the city recorded even elevated temperatures, with Ridge and Aya Nagar stations noting 41°C, while Palam and Lodhi Road logged approximately 39°C. As per the IMD, the heatwave thresholds were formally reached at three prominent weather stations — Safdarjung, Ridge, and Aya Nagar — indicating the beginning of Delhi’s first significant heat event of the year.

What’s concerning is the timing. Usually, Delhi surpasses the 40°C threshold in the second half of April. This year, the limit was surpassed in early April, echoing the pattern of 2022 when the initial heatwave occurred on 8th April. These early occurrences indicate a significant change in weather patterns and evoke serious worries for the upcoming months. Predictions indicate that temperatures will escalate in the upcoming days, with highs anticipated to increase by an additional 2 to 4°C.

A slight decrease in temperatures could occur in the second week of April, yet the overall seasonal forecast appears bleak. The IMD’s forecasts for April to June indicate a higher-than-average count of heatwave days. This not only threatens public health but also exerts significant strain on agriculture, water resources, and energy systems throughout the area. Historically, heatwaves in India have resulted in thousands of fatalities, with certain years experiencing severe consequences.

 In 1998, more than 2,500 individuals perished from severe heat conditions throughout North India, particularly in Uttar Pradesh, Bihar, and Orissa. The incident remains among the most severe heatwaves in India’s history, greatly impacting impoverished rural communities that have restricted access to cooling and water resources. In 2002, approximately 1,030 fatalities were documented in Andhra Pradesh, especially in coastal areas where temperatures exceeded 48°C.

A major heatwave in 2010 resulted in about 300 deaths in Gujarat and Rajasthan. Ahmedabad encountered several days with temperatures surpassing 46°C, leading to conversations about managing urban heat.

The 2015 heatwave ranked among the most devastating in recent history, claiming over 2,500 lives, with more than 1,700 occurring in Andhra Pradesh alone. Cities such as Hyderabad, Khammam, and Guntur experienced temperatures exceeding 47°C for several consecutive days.

At that time, it was noted as the fifth most lethal heatwave worldwide. In 2016, temperatures surpassed 48°C in Phalodi, Rajasthan, establishing a national record. Over 1,600 fatalities were recorded in different states such as Odisha, Maharashtra, and Telangana. In June 2019, Aurangabad, Gaya, and Nawada districts in Bihar recorded more than 150 deaths due to heatstroke within a single week. The elderly and impoverished communities were particularly impacted by water scarcity and insufficient health facilities. In 2024, between March and June, more than 700 deaths due to heatstroke were reported from 17 states.

A 2021 study featured in The Lancet Planetary Health indicates that heatwave-associated fatalities in India have risen by over 55 per cent between 2000–2004 and 2017–2021. According to the National Disaster Management Authority (NDMA), heatwaves resulted in more than 25,000 fatalities in India between 1992 and 2020, with a significant impact on states such as Andhra Pradesh, Telangana, Odisha, Uttar Pradesh, Rajasthan, and Bihar.

Heatwaves can have widespread impacts across various sectors, including human health, animal well-being, agriculture, forests, and more.

As temperatures rise, the human body struggles to maintain its coolness, leading to dehydration, cramps, fatigue, and, in extreme cases, heatstroke — a condition that can be life-threatening. At-risk populations, including children, seniors, expectant mothers, and those with chronic health conditions, are at the greatest peril. Individuals engaged in outdoor labour, like farmers, construction workers, and street vendors, face significant exposure and frequently do not have access to cooling, hydration, or breaks during the hottest times. The health hazards are exacerbated by inadequate infrastructure in various areas of India.

The restricted availability of cooling shelters, medical care, and up-to-date weather data hinders swift response efforts. Heat-related illnesses frequently go unreported, obscuring the actual extent of the issue.

The effects of heatwaves go further than just immediate health dangers. Elevated temperatures lower farming output by putting stress on crops and raising the need for irrigation. In areas such as Punjab, Haryana, and Uttar Pradesh, wheat and rice crops are particularly susceptible. Initial heat stress may cause “terminal heat” impacts that hinder grain development and greatly lower yields. In urban areas, the pressure on energy systems rises significantly because of the greater need for air conditioning and refrigeration. Power outages and water shortages occur more often, adding strain to public health systems and disturbing everyday life.

For companies, particularly those reliant on outdoor work, the decrease in productivity can be significant. The International Labour Organisation (ILO) states that by 2030, India may see a 5.8 per cent reduction in working hours from heat stress, significantly affecting economic productivity, especially in industries such as agriculture and construction. As temperatures rise and humidity decreases, the likelihood of forest fires grows significantly. In regions such as Uttarakhand, Himachal Pradesh, Chhattisgarh, and Odisha, dry forest vegetation becomes very combustible. In 2021, over 35,000 forest fire events were registered throughout India, with numerous incidents taking place during prolonged heatwave periods. These fires devastate biodiversity, emit carbon pollutants, and aggravate air quality. They furthermore jeopardise the livelihoods of communities living in forests and place additional strain on emergency response systems that are already overwhelmed by the heat.Research consistently connects the occurrence and intensity of heatwaves to climate change. The Intergovernmental Panel on Climate Change (IPCC) has cautioned that South Asia could face lethal heatwaves each year by 2050 due to ongoing warming trends, even if global temperature increases are restricted to 1.5°C.

India’s Ministry of Earth Sciences, in its 2020 report Assessment of Climate Change over the Indian Region, highlights that the frequency of warm days and nights has notably risen in recent years. The typical yearly temperature in India has increased by approximately 0.7°C since the early 1900s and is anticipated to increase by 2.4 – 4.4°C by this century’s end if efforts to mitigate remain inadequate.

To successfully tackle the rising danger of heatwaves, a thorough and tactical response plan is crucial. Enhancing the forecasting abilities of the India Meteorological Department (IMD) and guaranteeing the prompt distribution of early warnings in local languages — via mobile networks, radio, television, newspapers, social media, and community leaders — should be prioritised.Cities such as Ahmedabad have put into action Heat Action Plans (HAPs) that feature critical interventions like public cooling centres, adjusted school and work timings, and systems for hydration support.

These effective models ought to be reproduced and modified throughout the nation. Public awareness initiatives are equally essential, and officials must proactively disseminate safety guidelines—both dos and don’ts — through every available communication avenue to connect with various segments of the population.

Healthcare systems must be prepared to react efficiently. Healthcare workers need to be educated on recognising and treating heat-induced conditions, and medical institutions should be sufficiently equipped with essential supplies and resources during the hottest months of summer.

Urban resilience approaches — such as increasing tree canopy, promoting green roofs, and incorporating reflective materials in structures — can significantly diminish the urban heat island phenomenon and improve long-term living standards. Moreover, farmers require tailored support, including access to water, shade, and advice, to protect their livelihoods from extreme heat. In conclusion, an integrated, multi-faceted strategy — merging early warning systems, community engagement, healthcare readiness, climate-resilient city planning, and rural assistance — is essential to protect lives and livelihoods from the increasing threat of heatwaves in India.

(The writer is Former Executive Director of the National Institute of Disaster Management, Government of India. Views are personal)