New Delhi: India counts among heat stroke deaths only those deaths medically certified as having been caused by direct exposure to the sun, thereby capturing only 10% of the real figure, leaving out deaths due to high ambient temperature. Accurate reporting is essential to create informed policies to build resilience, at a time when India is grappling with increasingly intense and frequent heat waves and is vulnerable to rising temperatures due to climate change, experts say.

Heat waves killed about 6,167 people in India over eight years to 2018. Of that, government records show, 34% (2,081 deaths) were in 2015, the year that saw one of the world’s five deadliest heat waves on record, IndiaSpend reported on April 3, 2020.

India also does not recognise heat waves as a disaster under its disaster management law, thereby cutting it off from the government’s disaster response fund, experts said adding that this needs to change--the money is essential not only for relief but for building resilience, part of which involves creating early warning infrastructure.

Preparing for heat waves

A heat wave is defined differently for varying topographies. In the plains, the maximum temperature has to be 40°C or above; in coastal areas 37°C or more; and in hill regions 30°C or higher, according to the India Meteorological Department, which provides heat-wave forecasts for more than 300 cities. In India, heat wave conditions are usually experienced between March and July, with acute heat waves occurring mostly between April and June.

Currently, parts of Rajasthan are under heat wave alert, though this year the temperatures have been relatively lower than in preceding years.

About 100 cities and 23 state governments have partnered with the National Disaster Management Authority (NDMA) to develop Heat Action Plans (HAP) as adaptation measures for extreme heat events. The first Heat Action Plan was launched in 2013 by the Ahmedabad Municipal Corporation, which went on to become a template for other regions.

However, for these action plans and warning systems to be effective, India needs to invest far more than what has been done till date. “There are not enough resources available to build resilience against heat waves because they are not recognised under the National Disaster Management Act, 2005, making them ineligible for money from national or state disaster response funds,” said Chandra Bhushan, president and chief executive officer of the International Forum for Environment, Sustainability and Technology (iFOREST), a Delhi-based think-tank.

Unlike other extreme weather events, heat waves last much longer and have a protracted impact. A cyclone usually impacts a region for a day but heat waves could last for up to 15. “That is why money is needed to provide relief to the affected people and for additional investment in adaptation measures,” Bhushan told IndiaSpend. “This investment needs to come from the home ministry’s National Disaster Response Fund as it is the only fund in the country dedicated to deal with climate change fallout.”

Underreported deaths

Heat-related deaths are a crucial factor in determining adaptation policy but they are grossly under-reported in India.

Heat stroke deaths can be classified as direct deaths (due to exertion under direct sunlight) and indirect or non-exertional deaths (people who suffer a heat stroke due to high ambient temperature--such as those trapped inside homes with high room temperatures). Indirect deaths are noticed mostly among old people with comorbidities, said Dileep Mavalankar, director of the Indian Institute of Public Health (IIPH), the country’s first public health university in Gandhinagar. Mavalankar is closely associated with Ahmedabad’s heat action plan.

“If you just look for medically certified heat stroke deaths, they account for only 10% of total deaths due to heat waves. That’s because they only record easily recognisable direct deaths. Heat wave deaths are like an iceberg... 90% [which are indirect deaths] is not visible,” Mavalankar told IndiaSpend.

Compensation is an important reason for underreporting of heat stroke deaths. In states where families of heat stroke victims are compensated, authorities use a narrow definition and description of the circumstances of death, thereby recording only direct deaths, Mavalankar had explained to IndiaSpend in June 2017.

Availability for municipal ward and city-level morbidity and mortality statistics is still one of India’s biggest challenges. “In many cases, these [statistics] might be partially collected but they are not collated, rendering them unusable for better modelling and planning in terms of HAPs,” said Polash Mukerjee, programme lead for air quality and climate resilience at Natural Resources Defense Council (NRDC) India, an international environmental advocacy group.

India also needs capacity building in frontline medical and emergency health services. For example, the Ahmedabad HAP contains a component for training municipal health workers and other medical personnel in identifying symptoms of heat stress as well as other symptoms of heat-related illnesses, Mukerjee added.

The heat is on

Although favourable weather conditions have kept the country cooler this year, on average for six years to 2019, India has had 114 days of heat wave conditions every year.

There was only one major heat wave event over central and northwestern parts of India, which is prone to heat waves, said Madhavan Rajeevan, an atmospheric scientist and secretary at the Ministry of Earth Sciences. “This year heat waves have been a little subdued but we can expect heat waves over northwest India in June,” Rajeevan told IndiaSpend.

Extreme temperatures and heat waves are set to increase due to the changing climate. As global CO2 (carbon dioxide) emissions continue to rise, heat waves are likely to become more frequent and more intense, according to an October 2018 report by the Intergovernmental Panel on Climate Change, the United Nations body set up to assess climate science, IndiaSpend reported in August 2019.

The annual average temperature in India has risen by 2°C over 200 years till 2006. It is predicted to rise further by 1.5°-2°C by 2030. Within 50 years, 1.2 billion people in India would live in areas as hot as the Sahara, if greenhouse gas emissions keep rising.

A growing percentage of India’s population is getting exposed to heat waves as the average duration of a heat wave has increased by 150%, from two days in 2012 to almost five days in 2016. In 2012, just under 20 million people were exposed to heat waves compared to 60 million in 2016, a 200% increase, IndiaSpend reported in November 2018.

Scientists, who studied India’s 2015 heat wave, concluded that vulnerable regions including Andhra Pradesh and Telangana were likely to see intense heat waves once every decade instead of once every century.

While India’s policies target cities, India’s poorest areas are most vulnerable to heat waves. People living in underdeveloped parts of central India are most vulnerable to the health impacts of heat waves, according to the Heat Vulnerability Index for India, IndiaSpend reported in May 2017.

Action plans

In 2016, after the success of Ahmedabad Municipal Corporation’s heat action plan, the NDMA prepared guidelines for state governments to formulate action plans for prevention and management of heat waves. The are based on four key strategies: forecasting heat waves and enabling an early warning system, building capacity of healthcare professionals to deal with heat wave-related emergencies, community outreach through various media, and inter-agency cooperation as well as engagement with other civil society organisations in the region.

However, limited resources are hindering the adoption and roll-outs of these plans in several cities. “While some cities have emerged as a model for others, a much wider implementation of these HAPs is needed along with a robust institutional mechanism for building long-term community-level resilience,” said Mukerjee of NRDC. NRDC has been involved in the conceptualisation of India’s HAP strategy. “These HAPs require large additional allocation of resources... financial as well as additional regulatory and institutional capacities.”

Heat resilience is beneficial

Making HAPs more robust also makes economic sense, studies show. India is projected to lose 5.8% of working hours in 2030, a productivity loss equivalent to 34 million full-time jobs, either because it would be too hot to work or because workers would have to work at a slower pace, impacting the agriculture and construction sectors in particular, predicted a 2019 International Labour Organization report.

"Although most of the impact in India will be felt in the agricultural sector, more and more working hours are expected to be lost in the construction sector, where heat stress affects both male and female workers," said the report.

The impact of heat stress is not limited to sectors where employees are directly exposed to sunlight. Small industries, such as cloth-weaving units, which cannot afford air-conditioning, are also vulnerable to production losses due to a rise in temperatures, found a 2018 study prepared by the Energy Policy Institute at the University of Chicago (EPIC), a think-tank.

For every 1°C rise in temperature beyond 27°C on a hot day in India, productivity of workers drops by as much as 4%, said the study.

How To Effectively Fight Heat

  • India must report all-cause daily mortality through the year so that heat and cold wave deaths are properly recorded. This would result in better informed resilience planning, says Dileep Mavalankar of IIPH.
  • Heat Action Plans (HAPs) must be strengthened by including long-term components and mitigation measures that reduce the impact of extreme heat in the long run. For instance, energy-efficient buildings and passive cooling techniques such as cool roofs can serve as cost-effective solutions for reducing indoor temperatures. HAPs must incorporate these components not just for the new buildings but also existing structures, suggests Polash Mukerjee of NRDC.
  • Components of city planning, such as creating more green spaces and fewer built-up concrete areas, will reduce the effects of the Urban Heat Island effect (when the temperature inside the city limits is higher compared to the areas outside), says Mukerjee of NRDC.
  • While declaring a heat wave, the IMD should take into account the Wet-Bulb Temperature (a combined measure of temperature and humidity). That will be a more accurate metric. Currently, IMD only looks at the temperature, says Chandra Bhushan of iFOREST.

(Tripathi is an IndiaSpend reporting fellow.)

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