The incidence of ticks at all of Turku University’s research sites in Turku as well as in Helsinki has risen over the past 20 years, and they can still active into the fall, even after periods of freezing weather. Southwestern Finland and Uusimaa have reported 29 cases of tick-borne encephalitis and some 1,500 people have contracted Lyme disease, an illness caused by ticks carrying Borrelia burgdorferi.

Spring blossoms, dusty streets, distant fires and a lack of rain combine to create hazardous respiratory conditions.

Alder catkins (the pollen-rich flowers on alder trees) haven't reached their peak yet, but there are a lot of them. There can be four to five million pollen particles in a single catkin.