Climate change and atmospheric pollution are two environmental crises that are intimately connected. Extreme heat also deteriorates air quality and science has confirmed it.
The team from the Centro de Química Atmosférica y Medio Ambiente (CACE) at the Texas A&M University conducted research during the heatwave that hit Texas in August 2024, and the results are conclusive.
Since the pre-industrial era, the increase in greenhouse gases and aerosols has altered the planet’s balance, modifying geochemical cycles and affecting both air quality and people’s health.
The relationship between air quality and extreme heat: what the study says
Extreme heat directly affects air quality.
To understand how heat waves affect atmospheric chemistry, the experiment was carried out on the College Station campus between August 5 and September 3. At that time, temperatures ranged from 32 to 41 °C.
During that period, researchers took air samples both day and night. The absence of forest fires in the area allowed for analyzing the effects of extreme heat without the influence of smoke on the results.
Contaminants detected in air samples
Tests revealed the presence of key pollutants for public health, such as nitrogen oxides, ozone, volatile organic compounds (VOCs), and nanoparticles.
The results showed:
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High levels of ozone, oxygenated VOCs, and nanoparticles with a strong presence of acid, which increase with temperature.
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An increase in atmospheric pollutants resulting from chemical reactions in the air enhanced by solar radiation.
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The emission of natural VOCs such as isoprene by trees, in greater quantities during heatwaves, which can favor the formation of ozone in areas with abundant vegetation.
The role of vegetation during heatwaves
This last finding was key. During heatwaves, trees emit higher amounts of natural VOCs such as isoprene, a precursor to ozone that could be harmful in environments with abundant vegetation.
“It was surprising to see how these tree emissions increase during heatwaves and interact with atmospheric pollution,” explained Bianca Pamela Aridjis-Olivos, lead researcher and atmospheric chemistry specialist at Texas A&M University.
The specialist clarified that on their own, these emissions are not harmful. However, “when they react with other emissions under strong solar radiation, there is an increase in ozone and secondary organic aerosols, which pose a risk to public health.”
Protecting oneself from heat is essential
Extreme heatwaves are more frequent due to climate change.
In this sense, it is essential to protect oneself from extreme heat and avoid harmful consequences on health.
Experts recommend: avoid going out between 12 and 4 p.m., when temperatures and ozone levels are highest; limit outdoor physical activity, and stay informed about local air quality.
Keeping windows closed to reduce the entry of pollutants is also a good alternative.
Researchers conclude that the best way to protect public health long-term is to deepen the study of how climate change alters atmospheric chemistry and air quality.
