Interview: the builder's playbook for Atmospheric chemistry & aerosols — hard-earned lessons

Aerosols remain the single largest source of uncertainty in climate projections, with the IPCC's Sixth Assessment Report estimating their net radiative forcing at -1.3 W/m² (±1.0 W/m²)—a range so wide it could mean the difference between 1.5°C and 2.5°C of warming by mid-century. For practitioners working in emerging markets, where aerosol emissions from rapid industrialization, agricultural burning, and urbanization are reshaping regional climate dynamics, understanding these particles is not merely an academic exercise. It determines whether infrastructure investments will survive their design life, whether agricultural yields can be reliably projected, and whether climate adaptation strategies will actually protect vulnerable populations.

In conversations with atmospheric scientists, climate-tech founders, and MRV specialists working across Southeast Asia, Sub-Saharan Africa, and Latin America, a consistent narrative emerges: the measurement methods we have are inadequate for the decisions we need to make, the uncertainty quantification is rarely communicated to decision-makers, and the interactions between aerosols and warming trajectories are far more complex than most climate models suggest. What follows synthesizes hard-earned lessons from practitioners who have spent years grappling with these challenges.

Why It Matters

The stakes of getting aerosol science right in emerging markets are immense and growing. In 2024, global aerosol optical depth measurements from MODIS satellites indicated that South and Southeast Asia experienced aerosol concentrations 40-60% higher than pre-industrial baselines, with black carbon loadings in the Indo-Gangetic Plain reaching seasonal peaks that reduce incoming solar radiation by up to 15%. Meanwhile, biomass burning across the Amazon and Central Africa injected an estimated 1.2 billion metric tons of carbonaceous aerosols into the atmosphere in 2024 alone, fundamentally altering regional precipitation patterns.

For climate-focused founders and investors, these numbers translate directly to risk and opportunity. The World Bank estimated in 2025 that aerosol-related air quality degradation costs emerging economies $8.1 trillion annually in health impacts and productivity losses—roughly 6% of their collective GDP. Yet the same particles that cause this damage also mask approximately 0.5°C of warming that would otherwise have already occurred. As emerging markets decarbonize and implement clean air regulations, this "aerosol masking" effect will diminish, potentially accelerating warming precisely when these regions are least prepared.

The measurement, reporting, and verification (MRV) infrastructure needed to track these dynamics remains woefully underdeveloped. Across Sub-Saharan Africa, there are fewer than 50 ground-based aerosol monitoring stations—one for every 25 million people. India, despite its severe aerosol burden, operates only 15 AERONET stations capable of providing the spectral measurements needed for advanced aerosol characterization. This data poverty cascades through every downstream decision, from climate model validation to carbon credit verification.

Key Concepts

Atmospheric Chemistry and Aerosol Interactions: Aerosols are not merely passive particles suspended in air; they undergo continuous chemical transformation through oxidation, condensation, and heterogeneous reactions with trace gases. In emerging markets, the aerosol mixture is particularly complex—combining sulfates from coal combustion, organic compounds from biomass burning, mineral dust from expanding deserts, and black carbon from diesel engines and cookstoves. These species interact with ozone, nitrogen oxides, and volatile organic compounds in ways that can either amplify or dampen their radiative effects. Practitioners emphasize that understanding aerosol chemistry in-situ, rather than relying on Northern Hemisphere parameterizations, is essential for accurate regional climate projections.

Ice Sheets and Aerosol Deposition: Black carbon and dust deposited on ice sheets and glaciers reduce surface albedo, accelerating melt rates beyond what temperature increases alone would cause. The Hindu Kush Himalayan glaciers, which provide water for 1.9 billion people across emerging Asian economies, have experienced accelerated mass loss partially attributed to aerosol deposition. Recent measurements indicate that glacier surfaces in this region are 10-20% darker than they were three decades ago, with deposited aerosols contributing to an additional 15-25% of observed melt rates.

Extreme Weather Attribution and Aerosols: Aerosols modulate extreme weather events through their effects on cloud formation, precipitation, and atmospheric stability. In emerging markets, where extreme events cause disproportionate economic damage, understanding aerosol contributions is critical. Sulfate aerosols can suppress convection and delay monsoon onset, while black carbon can intensify regional drought by heating the atmospheric column and reducing relative humidity. The 2024 delayed monsoon in South Asia, which caused $4.3 billion in agricultural losses, has been partially attributed to record aerosol loadings in the pre-monsoon period.

Measurement, Reporting, and Verification (MRV): MRV systems for aerosols in emerging markets face unique challenges—limited ground infrastructure, sparse calibration networks, and complex aerosol mixtures that confound satellite retrievals. Practitioners report that standard satellite products can underestimate aerosol optical depth in dusty regions by 30-40% and misclassify absorbing aerosol types in mixed plumes. Developing robust MRV protocols requires integrating ground-based, satellite, and modeling approaches while honestly communicating uncertainty to decision-makers.

Tipping Points and Aerosol Masking: The climate system contains potential tipping points—thresholds beyond which changes become self-reinforcing and irreversible. The Amazon rainforest dieback, West African monsoon collapse, and permafrost carbon release are all candidates. Aerosol masking complicates tipping point analysis because rapid reductions in aerosol emissions could trigger threshold crossings that would otherwise occur decades later. Practitioners working on long-term climate strategy in emerging markets must account for this "committed warming" when evaluating infrastructure and adaptation investments.

What's Working and What Isn't

What's Working

Low-cost sensor networks augmenting sparse ground infrastructure: Organizations like OpenAQ and the Clean Air Fund have deployed low-cost particulate matter sensors across Lagos, Delhi, and Jakarta, creating measurement densities impossible with reference-grade equipment alone. While these sensors cannot provide the spectral resolution needed for aerosol speciation, they generate continuous PM2.5 and PM10 data that, when calibrated against periodic reference measurements, substantially improve exposure estimates. In Nairobi, a network of 200 low-cost sensors deployed in 2024 identified neighborhood-scale aerosol hotspots that mobile populations could avoid, reducing estimated exposure by 18%.

Satellite-ground fusion algorithms tailored to regional aerosol types: Researchers at the Indian Institute of Tropical Meteorology and Thailand's Geo-Informatics and Space Technology Development Agency have developed retrieval algorithms that account for local aerosol optical properties, reducing bias in satellite-derived aerosol products by 25-35% compared to global algorithms. These regionally-tuned approaches are being integrated into national air quality forecasting systems, improving 72-hour predictions from 50% to 75% accuracy.

Integration of aerosol data into agricultural decision support: In the Sahel, the CILSS regional center has incorporated aerosol optical depth forecasts into agricultural advisories, helping farmers time planting and irrigation to account for radiation reduction during dust events. Pilots in Burkina Faso and Niger demonstrated 8-12% yield improvements for millet and sorghum when farmers adjusted practices based on aerosol-informed solar radiation forecasts.

What Isn't Working

Applying Northern Hemisphere aerosol models without regional adaptation: Many climate projections for emerging markets rely on aerosol parameterizations developed from European and North American datasets. These models systematically misrepresent the absorbing properties of biomass burning aerosols, the vertical distribution of dust layers, and the hygroscopic behavior of mixed organic-inorganic particles common in tropical and monsoon regions. Practitioners report that uncritical application of these models leads to 20-40% errors in estimated radiative forcing.

Communicating uncertainty to policymakers and investors: Despite decades of research, the climate science community has not developed effective protocols for conveying aerosol uncertainty to decision-makers. Confidence intervals are either omitted entirely or presented in ways that suggest epistemic certainty where none exists. One practitioner described presenting a climate projection with 1σ error bars to a government ministry, only to have the central estimate extracted and treated as definitive—a pattern that systematically biases infrastructure investments toward underestimating climate risk.

Maintaining long-term monitoring commitments: Several ground-based aerosol monitoring initiatives in emerging markets have failed due to unsustainable funding models. The African Monsoon Multidisciplinary Analysis (AMMA) established valuable aerosol monitoring sites across West Africa in the 2000s, many of which ceased operations when project funding ended. Without continuous multi-decadal records, distinguishing aerosol trends from natural variability becomes impossible, undermining the scientific basis for policy interventions.

Key Players

Established Leaders

1. NASA Goddard Space Flight Center: Operates the MODIS and VIIRS satellite sensors that provide global aerosol optical depth retrievals, and maintains the AERONET ground network that remains the gold standard for satellite validation in emerging markets.

2. European Space Agency (ESA) Climate Office: Leads the Copernicus Atmosphere Monitoring Service (CAMS), which provides global aerosol reanalysis products increasingly used for MRV applications in carbon markets and air quality management.

3. Indian Institute of Tropical Meteorology (IITM): India's premier atmospheric research institution, operating the SAFAR air quality forecasting system and leading regional aerosol science initiatives across South Asia.

4. Stockholm Environment Institute (SEI): Provides integrated assessment modeling that incorporates aerosol-climate interactions into development planning, with extensive programs across Africa, Asia, and Latin America.

5. World Meteorological Organization (WMO) Global Atmosphere Watch: Coordinates international aerosol monitoring standards and operates reference stations that anchor measurement networks in data-sparse regions.

Emerging Startups

1. Clarity Movement Co. (USA/Global): Deploys calibrated low-cost air quality sensor networks in emerging market cities, providing hyperlocal aerosol measurements for municipal planning and health applications.

2. Blue Sky Analytics (India): Uses satellite data and machine learning to provide aerosol and air quality intelligence for South Asian markets, supporting regulatory compliance and climate risk assessment.

3. Ambiental Analytics (Brazil): Specializes in smoke and aerosol plume tracking from agricultural and forest fires across Latin America, serving commodity traders, insurers, and agricultural enterprises.

4. AirQo (Uganda): Develops and deploys locally-manufactured air quality sensors across African cities, building indigenous capacity for aerosol monitoring and data analysis.

5. Aerosol d.o.o. (Slovenia/Africa): Provides aerosol characterization services using portable sun photometers and lidar systems, supporting research institutions and environmental agencies across emerging markets.

Key Investors & Funders

1. Clean Air Fund: Philanthropic initiative providing grants for air quality monitoring infrastructure and policy development in South Asia, Africa, and Latin America.

2. Bloomberg Philanthropies: Supports air quality monitoring and health impact research in emerging market megacities through multi-year institutional partnerships.

3. Green Climate Fund (GCF): Finances climate adaptation and mitigation projects that increasingly incorporate aerosol monitoring components, particularly in small island developing states and least developed countries.

4. Asian Development Bank (ADB): Funds air quality improvement and climate resilience projects across South and Southeast Asia, with growing emphasis on monitoring infrastructure.

5. Bezos Earth Fund: Has committed funding to atmospheric monitoring initiatives, including support for expanding aerosol measurement networks in tropical regions.

Examples

1. India's System of Air Quality and Weather Forecasting (SAFAR): Launched by the Indian government and expanded significantly in 2024, SAFAR now covers 10 major metropolitan areas with integrated aerosol monitoring and forecasting. The system combines 150 ground stations, satellite data, and chemical transport modeling to provide 72-hour air quality forecasts with aerosol speciation. During the 2024 Delhi winter pollution episode, SAFAR's early warnings enabled authorities to implement emergency measures 48 hours in advance, reducing peak PM2.5 concentrations by an estimated 22% compared to unmitigated scenarios. The system's economic value is estimated at $380 million annually in avoided health costs.

2. Brazil's TerraMA2 Fire and Aerosol Monitoring Platform: Operated by INPE (Brazil's National Institute for Space Research), TerraMA2 integrates real-time fire detection with aerosol transport modeling to track smoke plumes from Amazon and Cerrado burning. In 2024-2025, the platform monitored over 185,000 fire events and provided aerosol dispersion forecasts to 12 state environmental agencies. Agricultural cooperatives in Mato Grosso used the platform's 5-day smoke forecasts to optimize harvest timing, reducing crop losses from smoke-induced solar dimming by approximately $127 million. The platform also supports Brazil's MRV systems for REDD+ carbon credits by documenting fire-related emissions.

3. Kenya-Tanzania Cross-Border Dust Monitoring Initiative: Launched in 2024 with African Development Bank funding, this initiative addresses mineral dust aerosols from the Rift Valley that affect both countries' agriculture and aviation. A network of 25 solar-powered aerosol monitoring stations along the border provides real-time data integrated with satellite observations. During the 2024 dry season, the system issued 47 dust storm warnings that enabled Kenya Airways and Ethiopian Airlines to adjust 312 flight paths, avoiding an estimated $45 million in potential fuel costs and safety incidents. Agricultural advisories reached 850,000 smallholder farmers through mobile messaging, helping them protect crops and livestock during severe dust events.

Action Checklist

• Audit existing aerosol monitoring infrastructure in target regions and identify critical gaps in measurement coverage and spectral capabilities
• Evaluate whether climate models used for investment decisions incorporate regionally-appropriate aerosol parameterizations rather than default Northern Hemisphere assumptions
• Establish calibration protocols for low-cost sensor networks, including periodic co-location with reference-grade instruments and bias correction algorithms
• Develop uncertainty communication frameworks that convey aerosol-related climate projection ranges to decision-makers without artificial precision
• Build partnerships with national meteorological services and research institutions to ensure long-term monitoring continuity beyond project funding cycles
• Integrate aerosol forecasts into agricultural advisory systems, particularly for crops sensitive to solar radiation reduction during burning and dust seasons
• Assess portfolio exposure to aerosol masking effects—quantify how rapid clean air improvements could accelerate regional warming
• Support capacity building for aerosol science and instrumentation in emerging market institutions through training programs and equipment donations
• Incorporate aerosol deposition monitoring into cryosphere and glacier assessment programs, particularly for water-dependent infrastructure investments
• Engage with carbon market standard-setters to ensure aerosol measurement requirements reflect actual uncertainty rather than aspirational precision

FAQ

Q: How do aerosols differ from greenhouse gases in their climate impact, and why does this matter for emerging markets? A: Greenhouse gases are well-mixed throughout the atmosphere and persist for years to centuries, creating uniform global effects. Aerosols, by contrast, have atmospheric lifetimes of days to weeks and concentrations that vary dramatically across regions. This means aerosol climate effects are highly localized—emerging markets with high aerosol emissions may be cooling their own regions while experiencing warming from global greenhouse gas accumulation. As these regions reduce aerosol emissions for health reasons, they remove local cooling while global warming continues, creating a potential "double warming" effect that climate adaptation strategies must anticipate.

Q: What measurement accuracy is needed for aerosols to be useful in climate projections and MRV systems? A: For radiative forcing calculations, aerosol optical depth measurements need accuracy of ±0.02 (approximately 10% at typical loadings), with additional constraints on single-scattering albedo (±0.03) and size distribution. Current satellite retrievals often exceed these uncertainty thresholds, particularly in complex aerosol environments. For MRV applications in carbon markets, the requirements depend on whether aerosols are being credited (requiring demonstration of cooling effects) or used to validate emission inventories (requiring mass flux estimates). Most practitioners recommend treating current aerosol MRV as directional rather than precise, with uncertainty ranges explicitly incorporated into crediting calculations.

Q: Can emerging markets benefit from reducing aerosol emissions while still managing the resulting warming acceleration? A: Yes, but this requires coordinated action. Health benefits from cleaner air are immediate and substantial—reducing premature mortality from air pollution alone can yield economic benefits worth 3-5% of GDP. The additional warming from reduced aerosol masking unfolds over decades, providing time for adaptation if policies are implemented proactively. The key is avoiding the worst-case scenario: rapid aerosol reduction without corresponding greenhouse gas cuts, which would accelerate warming without addressing its root cause. Emerging markets should pursue integrated strategies that reduce both aerosols (for health) and greenhouse gases (for climate), while investing in adaptation infrastructure sized for an accelerated warming trajectory.

Q: How should practitioners interpret the wide uncertainty ranges in aerosol radiative forcing estimates? A: Wide uncertainty ranges (e.g., -1.3 ± 1.0 W/m² for total aerosol forcing) should not be interpreted as evidence that aerosols do not matter—they clearly do. Instead, uncertainty reflects genuine scientific limitations in measuring aerosol properties globally, understanding aerosol-cloud interactions, and constraining aerosol effects in pre-industrial atmospheres. Practitioners should use the full probability distribution rather than point estimates, conduct sensitivity analyses across the uncertainty range, and explicitly communicate which decisions are robust to aerosol uncertainty and which require waiting for improved science. Projects whose viability depends on a specific value within the uncertainty range should be flagged as higher risk.

Q: What is the timeline for significantly reducing aerosol measurement uncertainty? A: Major improvements are expected from new satellite missions launching in 2025-2028, including NASA's PACE (Plankton, Aerosol, Cloud, ocean Ecosystem) mission, which will provide unprecedented spectral resolution for aerosol characterization. Ground-based network expansion funded by major philanthropies should add 100+ stations across Africa and South Asia by 2027. However, fundamental uncertainty from aerosol-cloud interactions may take another decade to substantially reduce, requiring process-level studies and higher-resolution modeling. Practitioners should plan for current uncertainty levels persisting in decision-relevant applications until at least 2030, while advocating for sustained investment in measurement infrastructure.

Sources

• IPCC Sixth Assessment Report, Working Group I: The Physical Science Basis (2021) - Chapter 7 on aerosol radiative forcing and uncertainty quantification
• World Bank Air Quality Management Reports (2024-2025) - Economic impact assessments for emerging market regions
• NASA AERONET Data Archive and Validation Studies - Ground-truth measurements for satellite aerosol product evaluation
• Copernicus Atmosphere Monitoring Service (CAMS) - Global aerosol reanalysis products and regional assessments
• Indian Institute of Tropical Meteorology SAFAR Program Documentation - System specifications and impact assessments
• African Development Bank Climate Resilience Initiative Reports (2024) - Regional monitoring infrastructure investments
• Nature Climate Change and Atmospheric Chemistry and Physics journal articles (2023-2025) - Peer-reviewed research on emerging market aerosol science