Report on Global Air Quality and Atmospheric Composition

Particulate Matter (PM2.5) and Sustainable Development

Particulate matter (PM2.5) continues to pose a significant threat to public health, directly challenging the achievement of SDG 3 (Good Health and Well-being). The 2025 Bulletin provides an overview of PM2.5 anomalies in 2024, highlighting regional disparities in progress towards air quality goals.

• Mitigation Success: Sustained pollution control measures in eastern China have resulted in a continued decline in PM2.5 levels, demonstrating positive action towards SDG 11 (Sustainable Cities and Communities).
• Pollution Hotspots: In contrast, northern India experienced significant pollution hotspots, indicating persistent challenges to public health and environmental sustainability in the region.
• Wildfire Impacts: Wildfire activity, exacerbated by climate change, led to above-average PM2.5 concentrations in Canada, Siberia, and central Africa. The most severe anomaly was recorded in the Amazon basin, where record wildfires degraded air quality. These events undermine SDG 13 (Climate Action) and SDG 15 (Life on Land), while posing growing risks to human health and infrastructure.

Aerosols: Complex Interactions with Climate and Health Goals

Aerosols present a complex challenge for environmental policy due to their dual capacity to both warm and cool the atmosphere. Understanding their impact is critical for developing integrated strategies that support SDG 3 (Good Health and Well-being) and SDG 13 (Climate Action).

1. Regional Trends: While aerosol concentrations have decreased in North America and Europe due to concerted efforts, they continue to rise in South Asia, South America, and northern latitudes, partly driven by increasing wildfire frequency.
2. Policy Impacts: International regulations reducing sulphur in shipping fuels have successfully improved air quality and public health, aligning with SDG 3. However, this has also reduced the cooling effect of sulphate aerosols, contributing to a slight acceleration of global warming and complicating efforts under SDG 13.
3. Integrated Approach: A comprehensive approach to managing emissions is necessary to protect the climate, ecosystems, and human health simultaneously, advancing multiple SDGs in a coordinated manner.

Regional Focus: Winter Fog in the Indo-Gangetic Plain

The Indo-Gangetic Plain, a densely populated and agriculturally vital region, faces escalating air pollution and winter fog episodes. This phenomenon is no longer a simple seasonal event but a symptom of environmental stress, impacting SDG 3 and SDG 11 (Sustainable Cities and Communities).

• Causative Factors: The increasing frequency and duration of fog are linked to pollution from vehicles, construction, heating, and the burning of agricultural and other vegetation.
• Recommended Strategies: Addressing this requires comprehensive strategies that align with sustainable development, including enforcing regulations on agricultural residue burning and promoting the adoption of cleaner energy for domestic use and public transport, in line with SDG 7 (Affordable and Clean Energy).

Wildfire-Induced Hotspots and Urban Air Quality

The 2024 wildfire season in the Amazon basin had significant consequences that extended far beyond the immediate fire zones. PM2.5 emissions resulted in a measurable degradation of air quality in distant, densely populated urban centers in Brazil. This underscores how the degradation of ecosystems under SDG 15 (Life on Land) directly compromises the goals of creating healthy and sustainable cities as outlined in SDG 11.

Atmospheric Composition Monitoring Infrastructure

The report emphasizes the foundational importance of a global, in-situ atmospheric monitoring infrastructure for tracking environmental changes and informing policy. The development and maintenance of this infrastructure are crucial for achieving the SDGs.

• Foundational Data: Ground-based monitoring networks are essential for calibrating and validating satellite data, which is particularly critical in developing countries where such infrastructure is sparse.
• Supporting the SDGs: Enhancing global monitoring capabilities is a direct investment in SDG 9 (Industry, Innovation and Infrastructure) and promotes global collaboration as envisioned in SDG 17 (Partnerships for the Goals).

Analysis of the Article in Relation to Sustainable Development Goals

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

• SDG 3: Good Health and Well-being: The article directly addresses health impacts, stating that particulate matter “remains a major health hazard” and that reducing sulphur emissions has “successfully cut premature deaths and childhood asthma.”
• SDG 11: Sustainable Cities and Communities: The article discusses air pollution in densely populated areas like the Indo-Gangetic Plain and urban centers in Brazil, linking pollution to vehicles, construction, and heating. It highlights the degradation of air quality in these urban environments.
• SDG 13: Climate Action: The article connects air pollution and climate change by discussing how aerosols can warm or cool the atmosphere, how wildfires are expected to increase as the climate warms, and how reducing certain pollutants (sulphate aerosols) can accelerate global warming.
• SDG 15: Life on Land: The article focuses heavily on wildfires, particularly in the Amazon basin, Siberia, and central Africa. It notes that these fires pose “growing risks for infrastructure and ecosystems” and are a major source of particulate pollution.
• SDG 7: Affordable and Clean Energy: As a solution to winter fog and pollution in the Indo-Gangetic Plain, the article explicitly suggests “promoting cleaner energy for cooking, heating, lighting and public transport systems.”
• SDG 9: Industry, Innovation and Infrastructure: The article underscores the critical need for a “global, fit-for-purpose in situ atmospheric monitoring infrastructure,” pointing out that such infrastructure is sparse in developing countries, which is essential for calibration and validation of satellite data.

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

• Target 3.9: By 2030, substantially reduce the number of deaths and illnesses from hazardous chemicals and air, water and soil pollution and contamination. The article’s focus on PM2.5 as a “major health hazard” and its link to premature deaths directly relates to this target.
• Target 11.6: By 2030, reduce the adverse per capita environmental impact of cities, including by paying special attention to air quality. The discussion of pollution hotspots in northern India, urban centers in Brazil, and the Indo-Gangetic Plain, caused by transport, industry, and construction, aligns with this target.
• Target 13.2: Integrate climate change measures into national policies, strategies and planning. The article calls for an “integrated approach to managing emissions” to protect both the climate and human health, which supports the integration of climate and air quality policies.
• Target 15.2: Promote the implementation of sustainable management of all types of forests, halt deforestation, and restore degraded forests. The mention of “record wildfires in the western Amazon region” highlights a failure in forest management and conservation, which is central to this target.
• Target 7.2: By 2030, increase substantially the share of renewable energy in the global energy mix. The recommendation to promote “cleaner energy for cooking, heating, lighting and public transport systems” is a direct call to action for this target.
• Target 9.1: Develop quality, reliable, sustainable and resilient infrastructure… with a focus on affordable and equitable access for all. The article’s emphasis on the need for “ground-based monitoring networks,” especially in developing regions where “infrastructure remains sparse,” points 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?

• Indicator 3.9.1 (Mortality rate attributed to household and ambient air pollution) and Indicator 11.6.2 (Annual mean levels of fine particulate matter (e.g. PM2.5 and PM10) in cities): The article is centered on measuring and modeling “Particulate Matter 2.5 microns in diameter or smaller (PM2.5).” It provides specific data points, such as the decline of PM2.5 in eastern China and hotspots in northern India, Canada, and the Amazon basin. These PM2.5 levels are the direct measure for these indicators.
• Indicator for Target 15.2: While not a formal UN indicator, the article implies that the **frequency, scale, and PM2.5 emissions from wildfires** can be used as a measure of forest health and degradation. The text highlights “record wildfires in the western Amazon region” and “wildfire activity” as key events degrading air quality and ecosystems.
• Indicator for Target 9.1: The article implies that the **density and distribution of ground-based atmospheric monitoring stations** can be used as an indicator. It explicitly states that this “infrastructure remains sparse” in developing regions, highlighting a clear metric for progress.

SDGs, Targets, and Indicators Summary

Source: wmo.int