Tag: Indo-Gangetic Plain

India’s Climate Challenge: Increasing Population Exposure to Compound Extreme Events

How is the growing population currently being affected, and how will it be impacted in the future by climate change-induced compound extreme events?  This study delves into exposure of the Indian population to compound precipitation-temperature extremes, specifically hot-dry and hot-wet extremes. The study reveals an increase of over 10 million person-years of exposure across various regions in India. In densely populated areas, the increase in hot-wet extremes has been more pronounced compared to hot-dry extremes, a trend that is expected to persist into the future. The research identifies the Indo-Gangetic plain and southern coastal areas as future hotspots.

India being world’s most populous country and sixth most vulnerable to climate extremes, faces escalating climate challenges. The country’s reliance on rain-fed agriculture intensifies the repercussions of increasingly frequent dry spells and heavy rainfalls, a result of erratic precipitation patterns observed since the beginning of the 21st century. Further exacerbating the crisis, India has been warming steadily since the 1980s. This rise in temperatures has led to a spike in heatwaves, causing substantial human fatalities and posing serious threats to health, agriculture, and natural ecosystems. The simultaneous or successive occurrence of these temperature and precipitation extremes, known as compound extremes, poses a greater societal and environmental risk as compared to their individual occurrence.

The journal paper titled “Population Exposure to Compound Precipitation-Temperature Extremes in the Past and Future Climate across India”, authored by Prof. Rajib Maity, Department of Civil Engineering, IIT Kharagpur; Prof. Harald Kunstmann, Institute of Meteorology and Climate Research (IMK-IFU), Karlsruhe Institute of Technology, Garmisch-Partenkirchen, Germany and Ms. Subhasmita Dash, Research Scholar, IIT Kharagpur provides a comprehensive analysis of the impact of climate change on the Indian population through the lens of compound extremes. The research, published in Journal of Hydrometeorology under the American Meteorological Society, delves into the increasing number of compound extremes events due to climate change and their societal consequences in terms of population exposure.

The study specifically focuses on compound precipitation-temperature extremes (hot-dry and hot-wet) across India, a region characterized by a wide variety of climatic regimes and significant variation in population density. Utilizing a copula-based statistical approach, the researchers evaluated changes in population exposure to these compound extremes in the past i.e. 1981-2020 and project future changes for the periods 2021-2060 (near future) and 2061-2100 (far future), under different future warming and socioeconomic development scenarios.

In recent years, from 2001 to 2020, India has experienced a notable increase in both hot-dry and hot-wet extreme weather events, surpassing the frequencies observed in earlier decades.  The study highlights that densely populated regions in India are expected to experience more adversity due to the hot-wet extremes in the future as compared to the hot-dry extremes. Considering both hot-wet and hot-dry extremes, the influence of climate is identified as the predominant factor towards the increase in exposure. This emphasizes the crucial role that climate change plays in amplifying the population exposure to compound extremes in a warmer future. Regions like the Indo-Gangetic Plain and the southern coastal areas are identified as future hotspots with maximum increases in exposure under projected warming and population scenarios.

This study explores the population exposure to an increasing number of hydroclimatic extreme events owing to the warming climate. It is well agreed that the extreme events are increasing in terms of frequency as well as intensity due to climate change and that the exposure to compound extreme events (concurrent occurrence of two or more extreme phenomena) affects population, ecosystems, and a variety of socioeconomic aspects more adversely. The results indicate an increase of more than 10 million person-year exposure from the compound extremes across many regions of the country, considering both near and far future periods.  The increase is as much as sixfold in many parts of the country, including the Indo-Gangetic Plain and southernmost coastal regions, identified as the future hotspots with the maximum increase in exposure under all the projected warming and population scenarios. The study helps to identify the regions that may need greater attention based on the risks of population exposure to compound extremes in a warmer future. It underscores the critical need to confront climate-related challenges arising from increasing exposure to compound extremes in India.

                                                                  
       Prof. Rajib Maity                                                             Ms. Subhasmita Dash
Department of Civil Engineering                                     Research Scholar        
IIT Kharagpur                                                                  IIT Kharagpur

Publication:
https://www.uni-augsburg.de/en/campusleben/neuigkeiten/2024/04/15/climate-hotspots-in-india/

Inputs By : Prof. Rajib Maity, Department of Civil Engineering, IIT Kharagpur
Email: rajib@civil.iitkgp.ac.in

Edited By : Poulami Mondal, Digital & Creative Media Executive (Creative Writer)
Email: poulami.mondal@iitkgp.ac.in, media@iitkgp.ac.in, Ph. No.: +91-3222-282007

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A Study on Rising Atmospheric Pollution in Rural India

Researchers from Indian Institute of Technology (IIT) Kharagpur have found increasing atmospheric pollution in rural India using Nitrogen Dioxide (NO2) measurements from satellites. Prof. Jayanarayanan Kuttippurath and Research Scholar Mansi Pathak of Centre for Ocean, River, Atmosphere and Land Sciences (CORAL) of IIT Kharagpur analysed the significant impact of urban pollution on the air quality of rural India by differentiating the pollution in two zones – rural and urban – and assessing the extent of air pollution in rural India. The researchers found that air pollution is not typically an urban phenomenon but can also affects the environment in rural perimeter. They conducted an analysis of the rural air quality to assess the extent of air pollution by measurements of NO2 through satellite imaging. The analysis carefully delineates the rural and urban regions of India, to examine the unheeded rural air pollution. Most air pollution assessments till date, discussed only the urban air quality issues. This analysis exposes increasing trends (0.05–0.44×1015molec./cm2/yr) of NO2 in the rural regions of India.

The study titled “Air Quality Trends in Rural India: Analysis of NO2 Pollution using Satellite Measurements,” highlights that rural sources account for 41 per cent of the overall NO2 pollution in India of which 45 per cent and 40 per cent are from transportation and power sectors, respectively. As the sources of NO2 are well coupled to the industrial and economic upliftment of a nation, the analyses for the rural regions show distinct seasonal changes with the highest value (2.0 1015 molecules per cm2) in winter and the lowest in monsoon (1.5 1015 molecules per cm2) seasons.

Prof. Jayanarayanan Kuttippurath
CORAL
IIT Kharagpur

“What we observe is that there is a decline in air quality in rural India in terms of our NO2 analysis, which is not beyond the threshold levels now, except in regions such as Delhi and suburbs and eastern India. However, given the positive trend in NO2 concentration, the high rate of urbanization and relocation of industries to suburbs, growing population and development activities, other regions of India would also cross the pollution threshold to impact the health of its people, and thus, our massive rural population. This is the real concern and it is the right time to take appropriate actions to control the atmospheric pollution in rural India,” explained Prof. Jayanarayanan Kuttippurath of CORAL, IIT Kharagpur. 

Air pollution is one of the biggest problems in India’s major cities. Comparison of pollutant-wise highest health risk values show that NO2 is about 19 times more harmful than Particulate Matter (PM) and about 25 times more risky than that of Sulphur Dioxide (SO2) . The population residing in the regions of high NO2 such as in the proximity of power plants, industries, cities, and in the areas above the permissible limit, are prone to be at high risk of adverse health effects such as asthma, bronchitis, pneumonia and cardiovascular diseases.

 Ms. Mansi Pathak
Research Scholar
IIT Kharagpur

Research Scholar, IIT Kharagpur and lead author of the paper, Ms. Mansi Pathak, stated, “We usually think the atmospheric pollution exists only in cities or it is just an urban threat. The air quality standards in rural regions are often neglected. However, our analysis suggests that it is high time to shift our focus to rural regions and examine the pollution levels and health issues of rural India. This is of paramount importance for a country like India, as rural areas have about 67 per cent of the country’s population (947 million) as of 2020 and public health today stands out to be the utmost priority globally.”

The indirect impact of NO2 on global climate change is not less with a net cooling effect attributed to the oxidation-fueled aerosol production.

Figure: The average concentration and long-term trends in atmospheric NO2 in India for the period 1997-2019.

High Nitrogen Oxide (NO) – which includes Nitric Oxide and Nitrogen Dioxide – levels in the troposphere can alter ozone formation, contribute to nitrate aerosol formation and acid deposition and affect regional climate.

Prof. Kuttippurath said though, other Indian rural regions are under permissible limits of CPCB, the increasing trends in NO2 would surpass the standards in future if no controlling measures are implemented, which is a serious concern.

This study suggests the need for taking action towards improving rural air quality to reduce the impact of air pollution on the large rural population of India. Although NO2 is a non-abundant gas, its indirect impact on global climate change is likely to be greater, with a net cooling effect attributed to the oxidation-fueled aerosol production. NOx levels in the troposphere can alter ozone formation, contribute to nitrate aerosol formation, and acid deposition and affect regional climate. The regions covered in this study are Indo-Gangetic plain, Central India, North-West India, Peninsular India, Hilly Region and North-East India where the authors analysed atmospheric NO2 concentration in different regions of India for the period 1997-2019.

Figure: Rural and urban atmospheric NO2 concentration in different regions of India for the period 1997–2019.

“Regulations similar to the Bharat Stage norms (for limiting vehicular emissions) need to be implemented in thermal power plants and industries located in both rural and urban regions, to restrict the overall NO2 pollution in rural India. Introducing new natural gas-fed power plants or using selective catalytic reduction (SCR) in older power plants can also reduce emissions, and thus, the NO2 pollution in rural India,” pointed out the researchers.

Publication Links: https://doi.org/10.1039/D2EM00293K

Media Coverage:

PTI UNI Indian Express
Economic Times Dainik Jagran Business Standard
The Print IBC 24 Neo Science Hub

Contact Person: Prof. Jayanarayanan Kuttippurath of CORAL, IIT Kharagpur
Email: jayan@coral.iitkgp.ac.in

Edited By : Poulami Mondal, Digital & Creative Media Executive (Creative Writer)
Email: poulami.mondal@iitkgp.ac.in, media@iitkgp.ac.in, Ph. No.: +91-3222-282007

Follow us on: Facebook – IIT Kharagpur; Twitter – @IITKgp;  Instagram – @iit.kgp; LinkedIn – Indian Institute of Technology
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Effective Control Technologies to Reduce Sulphur Dioxide Pollution In India

FLUE GAS DESULPHURIZATION REDUCES SO2 POLLUTION IN INDIA

A study by a team of researchers from IIT Kharagpur led by Prof. Jayanarayanan Kuttippurath from Centre for Oceans, Rivers, Atmosphere and Land Sciences (CORAL) found a significant decline in SO2 trends in India in the last decade, as compared to those in the previous three decades. The decrease in trend and concentration of SO2 is due to the environmental regulation and adaptation of effective control technologies such as scrubber and Flue Gas Desulphurization that shows the positive impact of technological advance and policy decisions to improve the air quality in India. The study represents temporal changes in SO2 concentrations over India in the past four decades (1980–2020). Thermal power plants (51%), and manufacturing and construction industries (29%) are the main sources of anthropogenic SO2 in India. The temporal analyses reveal that SO2 concentrations in India increased between 1980 and 2010 due to high coal burning and lack of novel technology to contain the emissions during that period. Both economic growth and air pollution control can be performed hand-in-hand by adopting new technology to reduce SO2 and GHG emission.

Prof. Jayanarayanan Kuttippurath
Centre for Oceans, Rivers, Atmosphere and Land Sciences (CORAL)
IIT Kharagpur

“SO2 is an atmospheric pollutant and can be converted to sulfate aerosols in high humid conditions. These aerosols can affect cloud reflectively, rainfall and regional climate by modifying the radiative forcing.  At high concentrations, SO2 affects adversely on human health and ecosystem as well. Therefore, continuous monitoring of its abundance in the atmosphere is highly warranted, as these kind of analyses would help making the policy decisions related to emissions. This particular study is serving that purpose,” remarked Jayanarayanan Kuttippurath, Centre for Oceans, Rivers, Atmosphere and Land Sciences (CORAL), IIT Kharagpur and the lead author of the study.

Sulphur dioxide (SO2) is one of the criteria pollutants that mainly released from the coal-based thermal power plants. At higher concentrations, it has hazardous affects on public health and environs. In this study, we find a significant decline in SO2 trends in India in the last decade, as compared to those in the previous three decades. The decrease in trend and concentration of SO2 is due to the environmental regulation and adaptation of effective control technologies such as Scrubber and Flue Gas Desulphurization showing the positive impact of technological advance and policy decisions to improve the air quality in India.

“Our analysis shows Indo-Gangetic Plain and Central and Eastern India regions as the SO2 hotspots in India. Although there is a relative reduction in SO2 in the last decade, the concentration of SO2 is still very high in these regions. Therefore, we need to continue our efforts to reduce SO2 emission in India, whether it is with innovative technology or environmental regulations,” said Vikas Kumar Patel, another author of the paper.

Fig 1: The SO2 trends in the last four decades in India. A rapid economic development in the 2001-2010 periods shows the largest trends among the decades. However, the recent decades with technological advance and environment policies help to reduce atmospheric SO2 concentrations and its trends.

An improved air quality monitoring network is needed to understand the spatial and temporal changes of pollutants, which would help to make policies relevant to improve air quality and to meet targeted reduction in emissions. The measurements and emissions in this study have uncertainities and are not computed in absolute figures. However, the trends computed are statistically significant across all Indian regions. Therefore, the findings have important implications for future environmental policies on India’s SO2 emissions and for understanding the impact of SO2 on regional climate, air quality, ecosystem dynamics, and public health. This study also provides a baseline for future studies that would critically examine changes in SO2 pollution as a result of the country’s socio-economic development.

“What we have found from our analysis is that, SO2 has been increasing in India for the past few decades, consistent with our economic development, but a declining trend in SO2 is found in the last decade (2010-2020). This is a good sign. The implementation of Bharat Stage norms on vehicular emissions, regulations for power plants to employ scrubber and FGD technologies, and policies encouraging the production of renewable energy may have contributed to this reduction in SO2 emissions,” added Prof. Kuttippurath.

Fig 2: Ground-based measurements also show reduction or stabilization of SO2 emissions; as shown for different cities here.

Due to rapid industrialization and urbanization in the past decades, India’s energy demand has been increased substantially with coal consumptions. The expansion of coal-based electricity generation in India is the primary cause of the country’s high emission. Although these help economic development of the country, the air pollution also increases along with it, which poses a health concern. Currently, India is one of the world largest emitters of SO2, accounting for more than 15% of global anthropogenic emissions. The situation warrants reduction SO2 emission in our country. However, majority of coal plants in India lack the Flue-Gas Desulfurization (FGD) technology necessary to adequately remove SO2 emissions. On the other hand, India’s power sector has seen an increase in renewable energy capacity, which would help to curb the pollution in India.

Prof. V K Tewari, Director, IIT Kharagpur stated, “India relies heavily on coal-based thermal power plants to meet its energy demands. Analysis of spatial and temporal changes in SO2 using accurate and continuous observations is required to formulate mitigation strategies to curb the increasing air pollution in India. Since 2010, India’s renewable energy production has also increased substantially when India adopted a sustainable development policy. The shift in energy production from conventional coal to renewable sources, solid environmental regulation, better inventory, and effective technology would help to curb SO2 pollution in India. India’s nationally determined contributions under the Paris Agreement includes achieving about 40% cumulative electric power installed capacity from non-fossil fuel-based energy resources by 2030. This commitment would help to reduce the dependency on the coal-based energy, and also help to curb the SO2 pollution in the future.”

Publication Links:

https://doi.org/10.1007/s11356-022-21319-2

Media Coverage:

Economic Times The Hindu Business Standard
Deccan Herald Financial Express Telegraph
Jagran The Print Siasat
Khabar Dunya The Hans India Gulf Today
Mongabay    

Contact Person: Prof. Jayanarayanan Kuttippurath, Centre for Oceans, Rivers, Atmosphere and Land Sciences (CORAL)
Email: jayan@coral.iitkgp.ac.in

Edited by : Poulami Mondal, Digital & Creative Media Executive (Creative Writer)
Email: poulami.mondal@iitkgp.ac.in, media@iitkgp.ac.in, Ph. No.: +91-3222-282007

Follow us: Facebook – IIT Kharagpur; Twitter – @IITKgp;  Instagram – @iit.kgp; LinkedIn – Indian Institute of Technology
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