The increase in the frequency, intensity and duration of heat waves Added to the greater number of forest fires that they cause, the quality of the air will worsen, damaging human health and ecosystems, anticipated this Wednesday the World Meteorological Organization (WMO).
In a new report, the agency predicts that the interaction between pollution and climate change will be punishing extra for hundreds of millions of people
The WMO Air Quality and Climate Bulletin 2022 edition focuses on the impact of smoke from wildfires in 2021, when hot and dry conditions exacerbated the spread of wildfires in western North America and Siberia, producing widespread rises in the levels of small particles harmful to health.
The WMO Secretary-General noted that as the planet warms, forest fires and pollution will increase associated air pollution, even in a low emissions scenario.
“In addition to impacts on human health, this will affect ecosystems as air pollutants settle from the atmosphere to the Earth's surface,” said Petteri Taalas.
He added that what has been observed so far is a foretaste of the future because an even greater increase in the frequency, intensity and duration of heat waves is expected, “which could lead to a worse air qualitya phenomenon known as the “climate penalty,” he said.
The WMO defined the climate penalty as the effect of amplification of climate change in tropospheric ozone productionwhich negatively impacts the air that people breathe.
The regions where the greatest climate penalty is projected, mainly in Asia, home to about a quarter of the world's population.
Climate change could exacerbate episodes of surface ozone pollution, which would have detrimental effects on the health of hundreds of millions of people.
The study explained that air quality and climate they are interconnected because the chemical species that lead to air quality degradation are typically emitted along with greenhouse gases. Thus, changes in one inevitably cause changes in the other.
The use of fossil fuels, a major source of carbon dioxide (CO2), also emits nitrogen oxide, which can react with sunlight to form ozone and nitrate aerosols.
Air quality, in turn, affects the health of the ecosystem as air pollutants are deposited from the atmosphere to the Earth's surface. Nitrogen, sulfur, and ozone deposition can negatively affect services provided by natural ecosystems, such as clean water, biodiversity, and carbon storage, and can affect crop yields in agricultural systems.
The Sixth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) includes scenarios on the evolution of air quality as temperatures increase in the 21st century.
The ozone level would increase in Asia
The Panel estimates that if greenhouse gas emissions remain high, such that global temperatures rise 3°C from pre-industrial levels by the second half of the 21st century, surface ozone levels would increase in heavily polluted areasparticularly in Asia.
This includes an increase in 20% in Pakistan, northern India and Bangladesh, and 10% in eastern China. Most of the increase in ozone will be due to an increase in emissions from the burning of fossil fuels, but a fifth will be due to climate change, probably due to the increase in heat waves, which amplify episodes of air pollution . Thus, heat waves, increasingly common due to climate change, would continue to cause a degradation of air quality.
Neutral emissions would limit ozone pollution
A carbon-neutral global emissions scenario would limit the future occurrence of extreme ozone air pollution episodes. This is because efforts to mitigate climate change by eliminating the burning of fossil fuels also would eliminate most emissions of ozone precursor gases caused by humans.
Particles, commonly called aerosols, have complex characteristics that They can cool or heat the atmosphere. High amounts of aerosols, and thus poor air quality, can cool the atmosphere by reflecting sunlight back into space or by absorbing sunlight in the atmosphere so it never reaches the ground.