Climate Change Impacts on Air Quality

Climate change alters the physical and chemical processes that govern the distribution, formation and removal of air pollutants. Rising temperatures accelerate the rates of photochemical reactions, increasing the production of secondary pollutants such as ground-level ozone. Changes in meteorological patterns, including altered precipitation, humidity and synoptic circulation, modulate the dispersion and deposition of particulate matter. Shifts in vegetation and soil moisture influence emissions of biogenic volatile organic compounds, further affecting secondary organic aerosol formation. Meanwhile, extreme events such as heatwaves and wildfires release large pulses of particulate matter and ozone precursors, exacerbating air pollution episodes. Coupled chemistry–climate models project that, under high-emission scenarios, ozone-related health burdens may rise, particularly in urban and industrial regions, even as PM2.5 concentrations respond to complex interactions between emission controls and climate feedbacks. These dynamics underscore the need for integrated air quality and climate policies to protect public health and ecosystems.

Research from Nature Portfolio

Recent studies have employed advanced numerical simulations to assess the joint health burden of air pollution and temperature under future climate scenarios. Under realistic socioeconomic pathways, end-of-century deaths attributable to non-optimal temperature and long-term pollutant exposure could quadruple relative to present levels. While pollution-related mortality may increase by a factor of five, temperature-related mortality is projected to rise sevenfold, signalling that warming alone will become a dominant risk factor for at least one fifth of the global population. These findings highlight that air quality improvements must be coupled with stringent climate mitigation to prevent a dramatic surge in premature mortality.

Climate Change Impacts on Air Quality publication trend

The graph below shows the total number of articles in climate change impacts on air quality across all publications each year (not limited to Nature Index journals).

Technical terms

PM2.5: Fine particulate matter with a diameter of less than 2.5 μm, able to penetrate deep into the respiratory tract and impair human health.

Tropospheric ozone: Secondary pollutant formed by photochemical reactions of nitrogen oxides and volatile organic compounds in the lower atmosphere under sunlight.

Representative Concentration Pathways (RCPs): Standardised greenhouse gas concentration trajectories used to project climate and air quality under various emission scenarios.

Biogenic emissions: Natural release of volatile organic compounds from vegetation and soils that contribute to secondary pollutant formation.

Stratosphere–troposphere exchange: The process by which air masses and trace gases move between the upper and lower atmosphere, influencing surface ozone levels.

References

1. Atmospheric health burden across the century and the accelerating impact of temperature compared to pollution. Nature Communications (2024).
2. China’s carbon-neutral policies will reduce short-term PM2.5-associated excess incidence of cardiovascular diseases. One Earth (2024).
3. Meteorology and Climate Influences on Tropospheric Ozone: a Review of Natural Sources, Chemistry, and Transport Patterns. Current Pollution Reports (2019).
4. The influence of temperature on ozone production under varying NOx conditions – a modelling study. Atmospheric Chemistry and Physics (2016).
5. Chemistry and the Linkages between Air Quality and Climate Change. Chemical Reviews (2015).
6. Meteorological modes of variability for fine particulate matter (PM2.5) air quality in the United States: implications for PM2.5 sensitivity to climate change. Atmospheric Chemistry and Physics (2012).
7. The effect of future ambient air pollution on human premature mortality to 2100 using output from the ACCMIP model ensemble. Atmospheric Chemistry and Physics (2016).