In a recent experimental study published in Atmospheric Chemistry and Physics, a collaborative research team from Germany and Norway conducted a quantitative study of lower tropospheric air pollution involving black carbon (BC)—also known as soot—aerosol particles over western and southern Europe between May and June 2020 using the BLUESKY aircraft. This study is intriguing as it measures the changes in atmospheric condition because of the sudden decrease in human activities during the first lockdown of the Covid-19 pandemic. The findings from this study were compared to a 2017 study also published in Atmospheric Chemistry and Physics and discovered a 48% reduction in BC mass concentrations (MBC) between the two timeframes.
While ground-level soot and its fine particulates can be harmful, atmospheric soot contributes directly to global warming due to their heat absorption properties from their dark-colored surface, thus heating up their surroundings. However, compared to long-lasting greenhouse gases such as carbon dioxide, soot has a much shorter lifespan, staying in the atmosphere from only a few days to weeks.
"Reduced soot emissions as a result of less burning of fossil fuels such as diesel, coal, oil, and wood would also improve the health of millions of people relatively quickly. Our measurements and model calculations also show that less soot in the atmosphere makes an important contribution to curbing climate change," explains Mira Pöhlker, an atmospheric scientist from TROPOS in Leipzig, and a co-author on the study. Pöhlker is also a researcher at the Max Planck Institute for Chemistry in Mainz and hopes that some changes in human behavior from the coronavirus era, such as increased teleconferencing, remote work, and the related cutback in flights and commuting, will continue. “I think that the pandemic has provided a trigger for a change in trends".
Pöhlker and the research team are presently conducting a new study while also bringing psychologists on board. The team wants to figure out if offers such as the German 9-Euro-ticket could bring about long-lasting changes in people's travel behavior.
"As well as a general reduction in traffic, it is also important to provide incentives to use modes of travel with lower emissions. In my opinion, heavily subsidized public transport is an important stimulus, and its effect on air pollution now needs to be quantified,” says Pöhlker.
Sources: Atmospheric Chemistry and Physics, Atmospheric Chemistry and Physics (2)
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