Growing coniferous trees produce fine particles, or aerosols to atmosphere. These reflect sunlight back to space and thus prevent the climate change.
The production of fine particles by coniferous trees – as all vegetation – is being observed in the SMEAR (Station for Measuring Forest Ecosystem – Atmosphere Relations) research programme, led by the University of Helsinki.

The emission of fine particles, or aerosols, from coniferous trees are being measured at three research stations in Finland: in Helsinki, in Juupajoki in Central Finland as well as in Savukoski in north-eastern Finland.
Coniferous trees produce compounds called aerosols, which not only reflect the sunlight back to space but also create clouds, which increase the reflection.
The research project is led by Professor, Mr. Markku Kulmala from the Division of Atmospheric Sciences at the University of Helsinki. According to Kulmala, the aerosols are produced mainly by coniferous trees, and this happens only when these trees are growing. The aerosols are hydrocarbons and terpenes, and they are created in connection with photosynthesis. Their lifetime is not very long: they descend to the surface of the Earth in rainfalls within one or two weeks.