In 2020, the first lockdowns in Europe are slowing down economic life in Europe. With positive effects on the air: The soot concentration in parts of Europe has been reduced by almost half, as researchers have found out. This is not only good for the climate, but also for health.
During the first lockdown of the corona pandemic, the mobility of many people in Europe was massively restricted. Air traffic almost came to a standstill and people drove less. However, this had a positive effect on air purity, as researchers find out. In 2017 and 2020, they measured the soot concentrations in the atmosphere over western and southern Europe. It turned out that these were 40 percent lower during the lockdowns.
The results reflected the strong impact of human activities on air quality and the importance of black carbon as a key air pollutant and climate driver, the authors write in their study, published in the journal Atmospheric Chemistry and Physics. Researchers from the Max Planck Institute for Chemistry, the University of Bremen, the Johannes Gutenberg University Mainz, the German Aerospace Center (DLR), the University of Leipzig and the Leibniz Institute for Tropospheric Research (TROPOS) were involved.
During the corona lockdowns at the beginning of 2020, the research team flew over Germany, the Benelux countries, Great Britain, France, Spain, Italy - i.e. large parts of Central, Western and Southern Europe with the German research aircraft HALO. It determined the mass of soot and the particle number concentrations in the lower part of the troposphere, which stretches from the ground to the stratosphere several kilometers above the ground. The team then compared the results with measurements from July 2017.
There was a significant improvement in air quality during the early pandemic. On average, the amount of soot in southern and western Europe fell by 41 percent. This was confirmed by analyzing traffic data and fuel consumption data during the lockdown periods. From the researchers' point of view, the limited mobility caused by the lockdowns was one of the reasons, and ongoing efforts to reduce soot emissions in Germany and Europe also contributed to this.
According to the researchers, soot near the ground is not only a part of the fine dust that is particularly harmful to health - in the atmosphere, the tiny particles also contribute to global warming because they heat up more due to their dark surface and give off heat to the environment. However, unlike long-lived greenhouse gases like carbon dioxide, soot is short-lived, staying in the atmosphere for only a few days to weeks.
"Reduced soot emissions through less burning of fossil fuels such as diesel, coal, oil or wood would also help the health of millions of people relatively quickly," said co-author Mira Pöhlker from TROPOS in Leipzig, according to a statement. "In addition, our measurements and model calculations show that less soot in the atmosphere makes an important contribution to curbing climate change." She hopes that some changes in behavior from the Corona period, such as more video conferences and working from home and thus fewer flights and trips to work, will be retained. "I think the pandemic has provided impetus for a turnaround."
In order to curb the rapid spread of the coronavirus and to combat the pandemic, most European countries reacted in the first half of 2020 with significant restrictions on mobility and economic activities. The lockdowns reduced fossil fuel burning, a major source of soot in the atmosphere, by about a third in early 2020. This decline is attributed to 90 percent less air traffic in Europe and a sharp reduction in road traffic. In the decades since World War II, Europe's emissions had never fallen so rapidly.