Q. Discuss what are the causes of heat waves in India? What measures should be taken by governments to deal with heat waves and their effects? Examine.
Introduction – Define what is heat wave and how serious is the problem.
Causes – Suggest causes of heat waves.
Measure – Suggest measures taken by government to combat heat wave.
Way Forward – Suggest some more innovative measures to combat heat wave.
Conclusion – End on a positive note.
A Heat Wave is a period of abnormally high temperatures, more than the normal maximum temperature that occurs during the summer season in the North-Western parts of India. Heat wave is declared when temperature remains at 45 degrees Celsius and above for two days running. It gets the “severe” tag when mercury touches 47 degrees. However, a heatwave is declared in a place such as Delhi after the mercury touches 45 degrees Celsius for a day. World Meteorological Organization defines a heat wave as five or more consecutive days during which the daily maximum temperature exceeds the average maximum temperature by five degrees Celsius. Heat Waves typically occur between March and June, and in some rare cases even extend till July. Heat waves are confined to the north, northwest, central and the eastern coastal regions of India.
Heat waves have been becoming increasingly frequent over the last years. Scientists say this is part of climate change that’s becoming a worldwide phenomenon and is likely to become more frequent. Since 2004, the country has experienced 11 of the 15 warmest years. Last year was the sixth-warmest since 1901, when preserving weather records started in the country. This year, 11 of the 15 hottest places in the world were located in India, the rest were in neighboring Pakistan, weather monitoring website El Dorado reported. Also this year, the heat wave spell has already stretched for 32 days, the second-longest spell ever recorded.
Further, high humidity compounds the effects of the temperatures being felt by human beings. Extreme heat can lead to dangerous, even deadly, consequences, including heat stress and heatstroke. To calculate the effect of humidity, Heat Index Values is used. The Heat Index is a measure of how hot it really feels when relative humidity is factored in with the actual air temperature. Environmental activists have suggested that India put in place a plan to tackle heat waves that are costing hundreds of lives every year. Since 2010, more than 6000 people have died in heat waves in the country, the Lok Sabha was told last year by health minister Harsh Vardhan.
A heat wave occurs when a system of high atmospheric pressure moves into an area. In such a high-pressure system, air from upper levels of our atmosphere is pulled toward the ground, where it becomes compressed and increases in temperature. This high concentration of pressure makes it difficult for other weather systems to move into the area, which is why a heat wave can last for several days or weeks. The longer the system stays in an area, the hotter the area becomes. The high-pressure inhibits winds, making them faint to nonexistent. Because the high-pressure system also prevents clouds from entering the region, sunlight can become punishing, heating up the system even more. The combination of all of these factors come together to create the exceptionally hot temperatures we call a heat wave.
Sinking air, associated with an area of high pressure, essentially traps the heat near the surface. When heat is trapped, health officials become concerned about not only heat exhaustion but air quality. These (heat wave) conditions, coupled with what we call an atmospheric inversion, essentially trap pollution near the surface instead of it going up higher. This process will trap the pollutants closer to people and can last for several days.
Other causes included are Decreased tree cover and over concretization. Reduction of water bodies such as lakes, wetlands around habitations (lakes have moderating influence on temperature in surrounding area). Global warming. Increased frequency of El Nino due to climate change.
Many states are affected during the Heat wave season, such as State of Andhra Pradesh, Telangana, Odisha, Gujarat, Rajasthan, Madhya Pradesh, Uttar Pradesh, Vidarbha region of Maharashtra, Bihar, Jharkhand and Delhi. The combination of exceptional heat stress and a predominantly rural population makes India, vulnerable to heat waves. Vegetable vendors, auto repair mechanics, cab drivers, construction workers, police personnel, road side kiosk operators and mostly weaker sections of the society have to work in the extreme heat to make their ends meet and are extremely vulnerable to the adverse impacts of heat waves such as dehydration, heat and sun strokes. Therefore, it is not surprising that these workers, homeless people and the elderly constitute the majority of heat wave casualties in India. A comprehensive heat preparedness and response requires involvement from not only government authorities but also non-governmental organizations and civil society. The local authorities should carry out a vulnerability assessment in order to identify these areas.
Timely warnings by IMD about a possible spike in temperatures, to alert the people in advance, in collaboration with the NDMA and SDMAs. ( Colour coding Heat alerts) Provide list of Dos and Don’ts Allowing sufficient provision of piped water supply for drinking to households, as well as places like schools, working places, and even public taps, for the convenience of the general public. Preparing a national, state, as well as district-level action plan, in coordination with public health authorities. Providing quick treatment to the affected, and spreading awareness about keeping ice packs in store, for quick relief. Allowing for an adjustment in the timings of schools, and workplaces. Finally, a vigilant monitoring and review of the implementation of the action plan, or the necessary prevention guidelines, by the concerned authorities. Heat stroke should be included in the list of disasters.
Capacity building / training programme for health care professionals at local level to recognize and respond to heat-related illnesses, particularly during extreme heat events.
These training programmes should focus on medical officers, paramedical staff and community health staff so that they can effectively prevent and manage heat-related medical issues to reduce mortality and morbidity.
Apart from these short term measures, long term efforts that government should undertake include increasing the green cover, better designed buildings, Sustainable development and all that which would help in the cause of climate change. This would go a long way to deal with Heat wave and reduce human impact.
According to a study by the Indian Institute of Technology (IIT) Gandhinagar, the frequency of severe heat waves in India will increase 30-fold by 2100 under a 2°C warming scenario. Under a business-as-usual scenario, heat-wave frequency might increase 75-fold. Heat wave is also called a “silent disaster” as it develops slowly and kills and injures humans and animals nationwide. Hence, measures have to be taken and taken fasr to minimize the deaths and damage caused due to heat waves.