The Finnish Meteorological Institute (FMI) is responsible for weather services for citizens and authorities in different special situations. Such special situations are, for example, hazardous weather events, dispersion of radioactive substances, dangerous chemicals in the air and also different disasters.
If there is a risk of a radiation accident, FMI produces weather forecasts including the site of an accident and the possible dispersion area and delivers information to both citizens and especially the authorities. In addition, FMI produces dispersion models and trajectory calculations for the authorities.
Duty meteorologists lay weather overviews including, for example, information about changes in wind conditions or the motion of rain areas; moreover, estimate reliability of weather prediction models in use at the site of an accident and in the possible area of influence.
Spreading of particles in the atmosphere can be forecast by using the long-range dispersion and dose assessment model SILAM developed at FMI. This model can be used for forecasting possible concentrations, if it is known at least something about the amount of emitted radioactive materials and its composition.
Regional rescue authorities are responsible for civil defense in radiation accidents. FMI supplies the weather and dispersion information required in radiation accidents for the use of radiation and rescue authorities. The Radiation and Nuclear Safety Authority (STUK) is responsible for preparation of instructions and orders to protect population, agriculture and other important activities in society. Distribution of iodine tablets, protection of population inside and some other activities concerning civil defense is concluded by the authority, which is in charge of organizing and leading the rescue operations. Depending on the extent of the hazard situation, decisions concerning safety operations are made by the rescue authorities at the municipal, provincial or governmental level.
The environmental radiation situation is continuously monitored by STUK. Also, FMI and the Defence Forces are monitoring environmental radiation at their own stations.
In radiation situations, FMI informs only about weather conditions and air currents: STUK and rescue authorities inform about the development of the accident and give instructions and orders for population and industrial life.
The functionality of plans and instructions and the cooperation between various sectors is regularly exercised.