Air Quality Modeling and Transboundary Pollution Assessment

Air quality modeling employs mathematical representations of atmospheric chemistry, emissions, transport and removal processes to simulate concentrations of pollutants such as particulate matter and ozone. These models range from regional chemical transport frameworks to global Eulerian and Lagrangian systems, integrating meteorological fields and detailed emission inventories. By quantifying the sources, sinks and pathways of pollutants, air quality models are indispensable for assessing transboundary pollution—where emissions from one region affect air quality in downwind areas. Such assessments inform international agreements, guide emission control policies and underpin health impact studies. Recent advances have improved spatial resolution, chemical mechanisms and data assimilation, enhancing the ability to detect seasonal and synoptic influences on pollutant episodes. Practical applications include forecasting severe haze events, evaluating the effectiveness of emission reduction strategies and identifying critical sectors for targeted regulation. As air pollution crosses national boundaries, robust modeling and cooperative assessment are central to effective global air quality management.

Research from Nature Portfolio

One foundational study analysed a twelve-year regional simulation over East Asia to disentangle the respective roles of emission control and meteorology in the Seoul metropolitan area. The work revealed that interannual variability in surface particulate matter was strongly correlated with changes in regional wind speed, with stagnant conditions exacerbating pollutant accumulation despite ongoing emission reductions. By holding anthropogenic emissions constant, the modelling demonstrated a clear negative correlation between wind-driven ventilation and particulate concentrations, underscoring the need to factor meteorological variability into air quality projections and policy evaluations.

Air Quality Modeling and Transboundary Pollution Assessment publication trend

The graph below shows the total number of articles in air quality modeling and transboundary pollution assessment across all publications each year (not limited to Nature Index journals).

Technical terms

Air quality modelling: The use of numerical simulation tools to represent emission sources, atmospheric transport, chemical reactions and removal processes that determine pollutant concentrations.

Chemical transport model (CTM): A class of air quality model that computes the spatial and temporal evolution of chemical species in the atmosphere based on emissions, meteorology and reaction mechanisms.

Transboundary pollution: The movement of air pollutants across political or geographical boundaries, resulting in downwind impacts on air quality and health.

Particulate matter (PM2.5): Fine aerosol particles with aerodynamic diameters of 2.5 micrometres or less, capable of penetrating deep into the respiratory tract.

Secondary organic aerosol (SOA): Particulate matter formed in the atmosphere through oxidation of volatile organic compounds, contributing substantially to fine aerosol mass.

References

1. Long-Range Transport of Secondary Inorganic Aerosol from China to South Korea. Environmental Science & Technology Letters (2024).
2. Long-range transport and airborne measurements of VOCs using proton-transfer-reaction mass spectrometry validated against GC-MS-canister data during the ASIA-AQ campaign. Environmental Research Letters (2025).
3. Regional contributions to particulate matter concentration in the Seoul metropolitan area, South Korea: seasonal variation and sensitivity to meteorology and emissions inventory. Atmospheric Chemistry and Physics (2017).