Soumya Dubey
2nd year Law Student at Dharmashastra National Law University
"Given the amount of human activity, urban environments are typically much warmer than their rural surroundings. The urban heat island effect is a phenomenon that is brought on by things like asphalt roads, concrete buildings, and less greenery. Particularly affected cities include Delhi and Nagpur, which experience greater temperatures and longer heatwaves"
India has consistently recorded the highest temperatures over the last three years. The annual rise in temperature is setting new records, and the situation for the residents is becoming more and more unbearable. As of May 2024, India is experiencing one of its most intense heatwaves in recent memory. This phenomenon is not only breaking temperature records but also leading to significant socio-economic and environmental challenges.[1]
It is undeniable that nations are making every effort to combat pressing issues such as urban planning, net carbon emission targets reduction, and global warming. In addition to efforts at the global and national level, local authorities are already leading the way in finding local solutions to these challenges. Yet, the situation is becoming worse every day.
El Niño and the thinning of the ozone layer in the atmosphere are not the only main variables causing global warming in recent times; a number of other minor factors also play a role. Here are some statistics that demonstrate that urban areas are the primary cause of the increasing severity of global warming with each passing year.
Air pollution as one of the major causes of increasing heat in the country
Cities are a key contributor to climate change, as urban activities are major sources of greenhouse gas emissions. Estimates suggest that urban areas are responsible for 70 percent of global CO2 emissions, with transport and buildings being among the largest contributors (IPCC, 2022).[2] Urbanization has caused the steady growth of pollution in Delhi. Today, Delhi finds itself among the world’s most polluted cities. Mitigating air pollution as well as greenhouse gases in Delhi without adversely impacting development remains a crucial goal.[3]
Transportation plays an important role in the total GHG emissions in most cities. In about one-third of the cities, more than 30% of total GHG emissions were from on-road transportation. In comparison, the emissions from railways, aviation, and waterways (<15% of total GHG emissions) were much lower. The variation of emissions in the transportation sector may due to a range of factors such as economic development, urban forms, traffic structures, and types of vehicle fuel.[4]
Atmospheric warming associated with climate change has the potential to increase ground-level ozone in many regions, which may present challenges for compliance with the ozone standards in the future. The impact of climate change on other air pollutants, such as particulate matter, is less certain, but research is underway to address these uncertainties. Ozone in the atmosphere warms the climate, while different components of PM can have either warming or cooling effects on the climate.[5]
Over consumption of energy is one central causes
Rising heat is driving up sales of ACs in India. Installation times of air-conditioners are stretching to two weeks in certain areas, as sales have surged up to three times compared to the previous year.[6] On average, a home air conditioner can use about 3,000 watts of electricity an hour. The contemporary overconsumption of energy is one central cause of GHG emissions and, subsequently, global warming and climate change.[7]
The hot air that exits from air conditioners does not directly contribute to global warming in the same way that greenhouse gases like carbon dioxide (CO2) do. The hot air produced by air conditioners is simply heat that has been removed from the indoor space and released outside. This heat does not contain greenhouse gases that trap heat in the atmosphere.
However, the overall impact of air conditioning on global warming is indirect and related to energy consumption. Air conditioners require electricity to operate, and the generation of electricity often involves burning fossil fuels such as coal, oil, and natural gas. The combustion of these fossil fuels releases greenhouse gases into the atmosphere, which contribute to global warming.
Therefore, while the hot air from air conditioners itself does not directly contribute to global warming, the energy consumption associated with air conditioning can indirectly contribute to climate change through the release of greenhouse gases during electricity generation. Efforts to improve energy efficiency, increase the use of renewable energy sources, and reduce overall energy consumption can help mitigate the indirect impact of air conditioning on global warming.
Urban Heat Island Effect
Given the amount of human activity, urban environments are typically much warmer than their rural surroundings. The urban heat island effect is a phenomenon that is brought on by things like asphalt roads, concrete buildings, and less greenery. Particularly affected cities include Delhi and Nagpur, which experience greater temperatures and longer heatwaves.
Urban heat islands may also contribute to climate change by increasing the demand for air conditioning during heat waves. When the energy for that air conditioning comes from the burning of fossil fuels, this results in emissions of heat-trapping greenhouse gases.[8]
Global warming makes cities warmer, while urbanisation intensifies this process via urban heat island generation and aerosol radiative forcing. The consequences of interactions among climate change, the urban heat island effect, and air pollution are expected to increase the risk of poor human health in cities globally by the middle of the twenty-first century. [9]
These were some of the main causes of increase in heat wave in the country in the past years and although, Developing a sustainable energy program and effectively managing natural resources are key to tackling this issue. Other important steps include reducing the demand for energy generated from fossil fuels, improving the efficiency of products over the life cycle, reusing and recycling materials where prudent, and switching to cleaner fuels in the transportation sector.[10]
Techniques like putting in cool roofs or planting shade trees can reduce air and surface temperatures in cities while lowering the energy required to cool buildings. This increases the dependability of the electric system, especially in the event of extreme weather.
In addition to lowering stormwater runoff and lowering the risk of flooding during heavy rainstorms, green roofs and some forms of cool pavements can reduce heat islands. Likewise, a larger tree canopy aids in providing protection from strong winds, erosion, and flooding.
By boosting walkability and mobility and minimizing urban sprawl, smart growth can reduce reliance on fossil fuel-powered transportation, cool urban areas, and facilitate people's access to cooling centers.
[1] The Current Heatwaves in India 2024: An Alarming Climate Change, (2024), https://www.aqi.in/blog/current-heatwaves-in-india-2024-an-alarming-climate-change/.
[2] Cities and climate change, UNEP, https://www.unep.org/explore-topics/resource-efficiency/what-we-do/cities-and-climate, (last visited, 21st June 2024).
[3] Hem H. Dholakia, Amit Garg, Climate Change, Air Pollution and Human Health in Delhi, India (January 2018), https://www.ceew.in/publications/climate-change-air-pollution-and-human-health-delhi-india.
[4] Air quality and climate change research by united states environmental protection agency, https://www.epa.gov/air-research/air-quality-and-climate-change-research, (last visited, 19th June 2024).
[5] Chester, M. V., and Cano, A. Time-based life-cycle assessment for environmental policymaking: greenhouse gas reduction goals and public transit (2016), https://doi.org/10.1016/j.trd.2015.12.003.
[6] Rising heat drives up sales of ACs in India; increase in installation times, Business standard, (2016), https://www.business-standard.com/india-news.
[7] Prashant kumar, Climate Change and Cities: Challenges Ahead (2021), https://www.frontiersin.org/journals/sustainable-cities/articles/10.3389/frsc.2021.645613/full
[8] Urban heat islands, center for science education, https://scied.ucar.edu/learning-zone/climate-change-impacts/urban-heat-islands#:~:text=An%20urban%20heat%20island%20(UHI,the%20surrounding%20natural%20land%20cover, (last visited, 21st june 2024).
[9] Prashant kumar, Climate Change and Cities: Challenges Ahead (2021), https://www.frontiersin.org/journals/sustainable-cities/articles/10.3389/frsc.2021.645613/full
[10] Prashant kumar, climate change and cities: challenges ahead (2021), https://www.frontiersin.org/journals/sustainable-cities/articles/10.3389/frsc.2021.645613/full
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