The past few days have seen the temperature rise to record levels in many parts of the country, particularly the northwest, central and eastern parts. Heatwave conditions have prevailed in some districts with the day temperature, at times, hovering between 45 and 50°C. Harsh summers in the northwest and Central India are not a new phenomenon but the temperature rise, coupled with long dry weather, in the early weeks of the summer season is rather unsettling. With the monsoon still a few weeks away, more spells of extreme heat and heatwave conditions may be in the offing.
A cross-cutting heat resilience policy or a national heat action plan clearly articulating measures is lacking.
The heat has resulted in greater demand for electricity, which, in turn, is causing power cuts in several states. This is being attributed to problems in the supply chain of coal for thermal power plants. In metros, coolers and air-conditioners are in short supply, while water scarcity is being reported in smaller cities and towns. Treating all this as the usual summer phenomenon will be wrong. Extreme temperature is a hazard to human health, livestock, crops and businesses. We need a structured policy response to address it.
The first step should be to accept science in the form of available and emerging scientific consensus. The Intergovernmental Panel on Climate Change (IPCC) has constantly warned of a rise in the number and intensity of heatwaves in all regions, along with longer warmer and shorter winter seasons. When the global warming level reaches 2°C, the heat extremes will often reach the critical tolerance thresholds for human health and agriculture, warned the last IPCC report released in August 2021. While temperatures in coastal regions may not rise at the same level, people and livelihoods would nevertheless be hit due to more frequent marine heatwaves. They will cause changes to the ocean heat systems, resulting in ocean acidification and reduced oxygen levels. IPCC reports, which are a synthesis of available evidence from different countries, warn that rising temperatures will get exacerbated in urban areas which are prone to the ‘heat island’ effect.
All these impacts will be felt in India, as the rise in annual mean surface air temperature is projected to be between 1.7 and 2°C, according to the Indian Network for Climate Change Assessment. The science on climate change, and its various manifestations, including temperature extremes, is clear. Attributing each heatwave to climate change will require greater advances in what is called the ‘attribution science’ but the general trend links greater intensity and frequency of heatwaves to man-made climate change.
The second step should be to identify population groups that are vulnerable to the adverse impact of heatwaves so that necessary measures could be initiated. Such an assessment is a part of the overall vulnerability assessment to climate change which is being prepared. The problem of heatwaves is here and now, so the vulnerability assessment for heatwaves needs to be taken up on a priority basis in the most-prone states and districts.
A template for such studies exists in the form of a few projects. For instance, a study in Odisha, done by the Indian Institute of Public Health (IIPH), Bhubaneswar, has found that people living in slums are more at risk of getting exposure to heat because of the housing structures, heat-trapping materials on the roof (asbestos and tin), overcrowding, lack of electric supply and access to water supply and exposure to additional heat during cooking. An earlier study by IIPH-Gandhinagar pointed to the need for a countrywide vulnerability assessment for heat. Using available data, it concluded that out of 640 districts in the country 10 districts are at ‘very high risk’ while another 97 districts are in the high-risk category. Most of them are in the central region.
Vulnerability assessment takes into account geographical location, vegetation, wind speeds etc that determine outside temperature and factors like ventilation and roofing that influence indoor temperature in human habitats. Within cities, some areas may be more vulnerable than others. All such hotspots need to be identified for mitigating risks. People in different strata of the society are at risk, but it is the poor who are more vulnerable. It is not just humans who feel the heat stress. Crops and livestock too are adversely affected. Agriculture scientists are working on how changing temperature profiles are beginning to impact agricultural yields. Heat stress is also adversely hitting milk production.
The policy response to extreme temperatures so far has been fragmented and short-term. The national and state change action plans, which have been around for close to 15 years, mention extreme weather conditions as one of the challenges but little action has resulted from such general plans. Some city municipalities have taken initiative to prepare heat action plans but implementation has been tardy. The Health Ministry came up with a National Action Plan on Heat-related Illnesses last year. States have been asked to record heat-related illnesses and report them to the Integrated Disease Surveillance Programme. However, a cross-cutting heat resilience policy or a national heat action plan clearly articulating medium and long-term measures is lacking. We also need a roadmap to develop new technologies and solutions for mitigating heat impacts.
We need to communicate relevant information on heatwave forecasts and warnings in an easily understandable format and language. Government agencies need to prepare and publicise to-do lists for general public, employers in specific industries like construction, rural employment and educational institutions. Simple solutions like painting roofs or avoiding the use of heat-absorbing materials for roofing, providing windows for cross-ventilation can bring down indoor temperatures. Engaging local groups and civil society in replicating such solutions can go a long way. The solutions to reduce heatwave impacts are linked with climate solutions — energy use, urban planning, energy efficiency, climate-resilient architecture, climate adaptation in agriculture and so on.