Spring arrived a month earlier than normal this year in Västerbotten, Sweden. A sign of spring is typically the start of the pollen season. Researcher Christos Katrantsiotis measures pollen levels at Umeå University.
He says an early spring does not automatically mean there will be pollen. A small piece of tape on the university's roof shows how much pollen is in the air currently. Katrantsiotis goes up to the roof every day to collect the previous day's catch and put in a new piece of tape.
an early spring does not automatically mean there will be pollen
There are four measurement stations in northern Sweden, in Umeå, Storuman, Piteå, and Sundsvall. All samples from the measurement stations are analyzed in Umeå.