People enjoying the warm weather outdoors this weekend may have noticed irritation of their eyes, nose and throat, as the dry spring weather has increased the number of harmful particles in the air.
Several factors influencing the quality of the outdoor air and impacting people's health can be found throughout Finland at present, says Pia Anttila, an air quality expert at the Finnish Meteorological Institute. Besides the cleaning of dust and gravel from the streets and pollen counts at their springtime worst, fine particulate matter from controlled burning of forests and fields in other countries in Europe have been transported in the atmosphere as far north as the city of Oulu.
The concentration of ozone in the lowest layer of the Earth's atmosphere is slightly elevated, worsening air quality throughout Finland – even in the smallest corners of Lapland.
"This naturally makes things more uncomfortable for people who are more sensitive," Anttila says.
She says current levels are not dangerous, but may cause symptoms in people who are spending lots of time outdoors.
Rain would bring relief
The Pollen Report from the University of Turku reports that birch flowering continues in the south and has begun in warm central areas, while alder flowering is coming to an end in the lower half of the country and is now moving north.
Weather experts predict rain next week, and Anttila says a good dousing will drastically reduce harmful particle counts in the air throughout the country.
"Skies are becoming more overcast in the south; by Vappu [the May Day holiday], things will start to get better. Particle counts should start to drop in the next few days as well," she says.
The precipitation will also bring respite from the street dust, Anttila says.
There have also been several recent reports of sand carried to Finland from the Sahara desert on jet streams, making for some spectacular sunrises and sunsets in many parts of the country.
Anttila says the sand does not have a harmful effect on air quality, as its particle concentration is very low and it is located at an altitude of about ten kilometers.