Smoke from wildfires aggravates global climate crisis

The anticipated increase in the frequency, intensity and duration of heat waves and, as a result, of wildfires, will worsen air quality, damaging health and ecosystems.

This follows from a new report from the World Meteorological Organization (WMO), which warns that the interaction between pollution and climate change will impose an additional “climate penalty” on hundreds of millions of people. The WMO Bulletin on Air Quality and Climate, published annually, reports on the state of air quality and its close links to climate change. The bulletin discusses a set of possible air quality outcomes under high and low greenhouse gas emissions scenarios. The 2022 WMO Air Quality and Climate Bulletin has a special focus on the consequences of wildfire smoke in 2021. As in 2020, high temperatures and dry weather conditions exacerbated the spread of wildfires in western North America and Siberia, which resulted in a general increase in the levels of small suspended particles, which constitute a health hazard. “As the planet warms, wildfires and related air pollution are expected to increase, even under a low emissions scenario. In addition to the consequences for human health, this situation will also affect ecosystems, given that air pollutants are deposited from the atmosphere on the Earth’s surface,” Professor Petteri Taalas, WMO Secretary-General, explained in a statement. “This has happened in the heat waves that occurred in Europe and China this year when stable conditions in the upper atmosphere, sunlight and low wind speeds led to high levels of pollution,” said Professor Taalas. “This is a preview of the future, as a further increase in the frequency, intensity and duration of heat waves is projected, which could further worsen air quality, a phenomenon called a ‘climate penalty’. added the professor.

The “climate penalty” refers specifically to the amplifying effect of climate change on ground-level ozone production, which has a negative effect on the air we breathe. The regions with the strongest predicted climate penalty, primarily Asia, are home to roughly a quarter of the world’s population. Climate change could exacerbate surface ozone pollution episodes, leading to detrimental health effects for hundreds of millions of people. The WMO Bulletin on Air Quality and Climate, the second in an annual series, and the associated animation on atmospheric deposition were released ahead of the International Day of Clean Air for a Blue Sky, which falls on 7 September. This year’s theme, spearheaded by the United Nations Environment Programme, The Air We Share, focuses on the transboundary nature of air pollution, while underscoring the need for collective action. The bulletin draws on input from experts from the WMO Global Atmosphere Watch network, which tracks air quality and greenhouse gas concentrations and thus can quantify the effectiveness of policies designed to limit climate change and improve air quality. Air quality and climate are interconnected because the chemical species that cause the degradation of air quality, in general, are emitted together with greenhouse gases. Therefore, changes in one inevitably produce changes in the other. The burning of fossil fuels (a major source of carbon dioxide (CO2)) also emits nitrogen oxide (NO), which can react with sunlight to form ozone and nitrate aerosols. Air quality, in turn, affects the health of ecosystems through atmospheric deposition, as air pollutants are deposited from the atmosphere on the Earth’s surface. Nitrogen, sulfur and ozone deposition can have a negative effect on the services provided by natural ecosystems, for example, clean water, biodiversity and carbon storage, as well as affect crop yields in agricultural systems . The European Union’s Copernicus Atmospheric Monitoring Service measures global concentrations of particulate matter. Inhalation of PM2.5 (ie particles with a diameter of 2.5 micrometers or less) over prolonged periods constitutes a serious health hazard. Sources of such particles include emissions from burning fossil fuels, forest fires, and windblown desert dust.

Raging wildfires generated exceptionally high concentrations of PM2.5 in Siberia, Canada, and the western United States in July and August 2021. PM2.5 concentrations in eastern Siberia reached never-before-seen levels, driven primarily by rising high temperatures and dry soil conditions. Total estimated annual emissions in western North America were in the first five years of the 2003-2021 period, with PM2.5 concentrations far exceeding World Health Organization recommended limits. On a global scale, observations of the annual total area burned show a downward trend over the last two decades, as a result of fewer fires in savannahs and grasslands. However, on a continental scale, upward trends have been observed in some regions, for example parts of western North America, the Amazon and Australia.

Source-listindiario.com