The number of cars on Finnish roads has decreased dramatically as residents work from home to avoid spreading coronavirus.
Road traffic is down by 30 percent, according to Traffic Management Finland.
"Air quality has improved thanks to fewer vehicles on the roads," Piia Anttila, an air quality expert at the Finnish Meteorological Institute (FMI), said.
Less traffic means less pollution and fewer fine particles in the air. Weather conditions also affect the quality of the air we breathe, according to Anttila.
"Some pollution increases in sunshine whereas others decrease when it rains. This makes it difficult to determine what the effect of the restrictions that came into force this week have been," she explained.
Air traffic volumes this past Wednesday, 18 March, were 50 percent lower than one year ago. Airline pollution is further expected to decrease in the coming weeks due to cancelled flights and travel restrictions.
Industrial pollution levels have, however, remained steady as lifestyle tweaks have not impacted the need for power and heat.