Air pollution health and economic co-benefits of keeping warming below 2 °C in India – Nature

Report on the Health and Economic Co-Benefits of Climate Action in India

Executive Summary

This report presents a comparative assessment of two mid-century emission pathways for India: a Business-as-Usual (BAU) trajectory and a 2°C Warming Scenario (2°C-WS) aligned with the Paris Agreement. The analysis reveals that current emission trends will severely deteriorate air quality, leading to significant adverse health and economic impacts that impede progress toward the Sustainable Development Goals (SDGs). Conversely, adopting stringent climate actions to meet the 2°C target offers substantial co-benefits for public health and economic productivity. The 2°C-WS could prevent approximately 0.77 million premature deaths and 18.7 million Disability-Adjusted Life Years (DALYs) annually by mid-century, generating an economic benefit of €18.9 billion per year. Achieving these outcomes requires accelerated climate action and the integration of clean air policies, with a focus on the domestic, energy, and waste sectors. These findings underscore the critical synergy between SDG 13 (Climate Action), SDG 3 (Good Health and Well-being), and SDG 8 (Decent Work and Economic Growth).

1. Introduction: Aligning Climate Action with Sustainable Development Goals

The urgent need to reduce greenhouse gas (GHG) and particulate matter emissions is central to achieving the Paris Agreement’s net-zero target and advancing the 2030 Agenda for Sustainable Development. In India, chronic exposure to fine particulate matter (PM_2.5) presents a significant public health crisis, directly challenging the attainment of SDG 3 (Good Health and Well-being). In 2021 alone, PM_2.5 exposure was responsible for 0.95 million premature deaths. This report evaluates the health and economic consequences of air pollution under two distinct future scenarios, providing a quantitative basis for policies that integrate climate mitigation (SDG 13) with public health and sustainable economic development (SDG 8).

2. Comparative Analysis of Emission Scenarios and Air Quality

2.1. Business-as-Usual (BAU) Pathway Projections

The BAU pathway, which assumes the continuation of current policies and mitigation measures, projects a grim outlook for India’s air quality and its alignment with SDG 11 (Sustainable Cities and Communities). By mid-century, ambient PM_2.5 exposure is projected to range from 13 to 136.1 µg m⁻³. This trajectory indicates a failure to control pollution, with significant negative consequences for public health.

2.2. 2°C Warming Scenario (2°C-WS) Projections

The 2°C-WS pathway, which incorporates the stringent measures necessary to limit global warming, demonstrates the profound air quality co-benefits of robust climate action. Under this scenario, ambient PM_2.5 exposure is projected to decrease significantly, ranging between 7.4 and 84.4 µg m⁻³. This reduction represents a major step toward creating healthier living environments and achieving the clean air targets implicit in SDG 3 and SDG 11.

3. Health and Socio-Demographic Impacts: A Focus on SDG 3

3.1. Projected Health Burden under the BAU Pathway

Following the BAU pathway would result in a severe escalation of the public health burden, undermining progress on SDG 3. Projections for 2050 indicate:

• An increase in annual premature deaths from 0.72 million (2015 baseline) to 2.12 million.
• An increase in Disability-Adjusted Life Years (DALYs) from 24.2 million to 51.6 million.
• Low Socio-Demographic Index (SDI) states are expected to bear the largest share of this burden, accounting for 46% of premature deaths.

3.2. Health Co-Benefits of the 2°C Warming Scenario

Adherence to the 2°C-WS offers transformative health benefits, directly contributing to the achievement of SDG 3 targets. By mid-century, this pathway could:

• Prevent an estimated 0.77 ± 0.19 million premature deaths annually compared to the BAU scenario.
• Avert 18.7 ± 4.3 million DALYs annually.
• Reduce total premature deaths to 1.35 million and DALYs to 32.9 million.

3.3. The Role of Socio-Demographic Drivers

The analysis identifies population growth and aging as the predominant drivers that will shape future health burdens, projected to increase the burden by 150-200%. While projected improvements in baseline mortality rates for most non-communicable diseases (NCDs) will partially offset this effect, the data highlights the increasing vulnerability of an aging population. This underscores the need for healthcare systems to be strengthened in parallel with pollution control measures to fully realize the goals of SDG 3.

4. Sectoral Contributions and Policy Implications for Sustainable Development

4.1. Emission Source Apportionment

Identifying the primary sources of pollution is critical for targeted policy interventions that support multiple SDGs. Under the BAU pathway, key contributors to health fatalities include:

1. Domestic Sector: Emissions from household activities, impacting SDG 7 (Affordable and Clean Energy).
2. Energy Sector: Emissions from power plants and industry, also linked to SDG 7 and SDG 12 (Responsible Consumption and Production).
3. Waste Sector: Emissions from waste management, particularly in high-SDI states, relevant to SDG 11.
4. Transportation Sector: Vehicular emissions impacting urban air quality and SDG 11.

Secondary PM_2.5, formed from precursor gases, is a dominant driver of the health burden and is projected to remain a significant challenge even under the 2°C-WS.

4.2. Mitigation Priorities for Achieving Health and Climate Goals

The 2°C-WS demonstrates that substantial health benefits can be achieved by targeting specific sectors. To maximize synergies between SDG 3, SDG 7, SDG 11, and SDG 13, policy efforts should prioritize:

• Abatement of primary PM_2.5, which accounts for two-thirds of avoidable deaths.
• Emission controls in the industrial, biomass burning, and domestic sectors, particularly across the Indo-Gangetic Plain.
• Reduction of emissions from transport and waste management in high-SDI states.
• Greater emphasis on reducing precursor gas emissions to control the formation of secondary PM_2.5.

5. Economic Consequences and Alignment with SDG 8

5.1. Economic Losses under the BAU Pathway

Failure to control air pollution will impose a substantial economic penalty, hindering progress toward SDG 8 (Decent Work and Economic Growth). By 2050, the BAU pathway is projected to result in an aggregated annual economic loss of €75.5 billion due to the air pollution-related health burden. This loss of productivity impedes the growth of human capital and national economic potential.

5.2. Economic Co-Benefits of Climate Action

Investing in climate action yields significant economic returns. By adopting the 2°C-WS pathway, India can:

• Reduce the annual productivity loss to €56.6 billion.
• Achieve a net economic gain of €18.9 billion annually compared to the BAU scenario.
• This benefit is equivalent to 0.12% of India’s projected GDP, providing a powerful economic justification for aligning with SDG 13.

6. Conclusion and Recommendations for Integrated Policy

The evidence presented in this report confirms that ambitious climate action is not only essential for environmental stability but is also a direct investment in public health and economic prosperity. The severe health and economic costs of the BAU pathway stand in stark contrast to the substantial co-benefits of the 2°C-WS. Achieving India’s Sustainable Development Goals requires an integrated policy approach that recognizes the interconnectedness of climate, air quality, health, and the economy.

Recommendations:

• Accelerate Climate Action: India should accelerate the implementation of policies aligned with the 2°C warming target to unlock significant health and economic co-benefits, directly supporting SDG 13.
• Integrate Clean Air and Health Policies: National and sub-national strategies must combine air pollution control with public health initiatives to address the rising burden of NCDs and achieve SDG 3.
• Target Key Emission Sectors: Prioritize emission control measures in the domestic, energy, transport, and waste sectors, fostering progress on SDG 7, SDG 11, and SDG 12.
• View Pollution Control as an Economic Investment: Frame air pollution control not as an expenditure but as an essential investment in human capital that strengthens economic growth and advances SDG 8.

Analysis of Sustainable Development Goals in the Article

1. Which SDGs are addressed or connected to the issues highlighted in the article?

The article addresses several Sustainable Development Goals (SDGs) through its focus on the interconnected issues of air pollution, climate change, public health, and economic development in India. The following SDGs are most relevant:

• SDG 3: Good Health and Well-being: The core of the article is the assessment of health impacts from air pollution. It quantifies premature deaths and disability-adjusted life years (DALYs) caused by PM_2.5 exposure, directly aligning with the goal of ensuring healthy lives.
• SDG 13: Climate Action: The entire study is framed around climate action. It compares a “business-as-usual” (BAU) emissions pathway with a “2°C warming scenario (2°C-WS),” which is a direct response to the Paris Agreement’s goals and the urgent need for climate mitigation discussed in the article.
• SDG 11: Sustainable Cities and Communities: The article explicitly discusses deteriorating “air quality in India” and measures ambient PM_2.5 levels, which are critical environmental issues for urban and peri-urban populations. This connects to the goal of making human settlements safe, resilient, and sustainable.
• SDG 8: Decent Work and Economic Growth: The analysis extends to the “severe… economic impacts” of air pollution. It calculates the economic losses in terms of Gross Domestic Product (GDP) and productivity, linking environmental health directly to sustainable economic growth.
• SDG 7: Affordable and Clean Energy: The article identifies emissions from the “energy” sector as a “pivotal” contributor to the health burden. This highlights the need for a transition to cleaner energy sources to mitigate both air pollution and climate change, which is the focus of SDG 7.

2. What specific targets under those SDGs can be identified based on the article’s content?

Based on the article’s detailed analysis, several specific SDG targets can be identified:

1. Target 3.9: By 2030, substantially reduce the number of deaths and illnesses from hazardous chemicals and air, water and soil pollution and contamination.
   • Explanation: The article is centered on this target. It estimates that the 2°C-WS could “prevent 0.77 ± 0.19 million annual premature deaths and 18.7 ± 4.3 million DALYs by mid-century” that would otherwise be caused by ambient PM_2.5 exposure.
2. Target 13.2: Integrate climate change measures into national policies, strategies and planning.
   • Explanation: The article advocates for this integration by stating, “India should accelerate climate actions to meet 2°C target and align clean-air and health policies for substantial health benefits.” It analyzes two different policy pathways (BAU vs. 2°C-WS), demonstrating the effect of integrated climate planning.
3. Target 11.6: By 2030, reduce the adverse per capita environmental impact of cities, including by paying special attention to air quality and municipal and other waste management.
   • Explanation: The article directly addresses this by measuring and projecting “ambient PM_2.5 exposure” levels, noting that they “remain above the World Health Organization’s (WHO) air quality guideline.” It also identifies emissions from “waste management” as a significant contributor to the health burden in high SDI states.
4. Target 8.4: Improve progressively, through 2030, global resource efficiency in consumption and production and endeavour to decouple economic growth from environmental degradation.
   • Explanation: The article quantifies the economic cost of environmental degradation. It estimates that under the BAU pathway, the “aggregated annual economic loss attributable to air pollution health burden would be 75.5 billion… Euros by 2050.” By showing that climate action could yield an “economic benefit of climate actions” of 18.9 billion Euros, it makes a case for decoupling economic well-being from polluting activities.
5. Target 7.2: By 2030, increase substantially the share of renewable energy in the global energy mix.
   • Explanation: While not explicitly measuring renewable energy share, the article implies the importance of this target by identifying “emission controls in the domestic, energy, and waste sectors” as “pivotal.” The 2°C-WS scenario inherently requires a transition away from fossil fuels (a major source of energy sector emissions) towards cleaner energy, thus connecting directly to this target.

3. Are there any indicators mentioned or implied in the article that can be used to measure progress towards the identified targets?

Yes, the article provides specific quantitative and qualitative indicators that align with the official SDG indicators for measuring progress.

1. For Target 3.9:
   • Indicator 3.9.1 (Mortality rate attributed to household and ambient air pollution): The article provides direct measurements for this indicator. It quantifies “annual premature deaths” and “disability adjusted life years (DALYs)” attributable to ambient PM_2.5 exposure. For example, it states that chronic exposure “claimed 0.95 million… premature deaths and 27.4 million… DALYs in 2021 in India.”
2. For Target 11.6:
   • Indicator 11.6.2 (Annual mean levels of fine particulate matter (e.g. PM_2.5) in cities (population weighted)): The article is replete with this data. It reports that “annual population-weighted ambient PM_2.5 exposure ranged between 14.6–126.4 µg m⁻³ in the baseline” and projects it to be between “7.4 and 84.4 µg m⁻³ under 2°C-WS.”
3. For Target 13.2:
   • Indicator 13.2.1 (Number of countries that have communicated the establishment or operationalization of an integrated policy/strategy/plan): The article provides qualitative evidence of such policies. It mentions India’s commitment to the “Paris Agreement’s net-zero target” and the implementation of domestic policies like the “National Clean Air Program launched in 2019.” The entire analysis of the 2°C-WS pathway serves as a model for an integrated strategy.
4. For Target 8.4:
   • Proxy Indicator (Economic losses from environmental degradation): While not a formal SDG indicator, the article provides a powerful metric to track the economic dimension of decoupling. It calculates the “net productivity loss” from air pollution, estimating it at “75.5 billion… Euros by 2050” under the BAU scenario and quantifying the potential economic gain from mitigation as “18.9 billion… Euros annually.” This is also presented as a “percentage share of projected GDP,” which would be 0.12% in India.

4. Summary Table of SDGs, Targets, and Indicators

Source: nature.com