In areas where there’s vast amounts of forests and the forests are important part of the economy, it becomes quite clear that forest management itself is kind of a form of geoengineering. What kind of forests are there: which tree species, how are the forests managed or not managed generally? All these affect the albedo value of the forests. If you’re a forest owner, you can take this to account. For example, coniferous forest albedo is lower than that of deciduous forests. Birch’ albedo is equivalent to the albedo of a clear-cut site.
Climate-cooling properties of forests
- Photosynthesis absorbs carbondioxide, the forest is generally a carbon sink.
- Forests increase atmospheric fine particle (aerosol) formation. Aerosols reflect radiation back into space, and increase cloud formation.
- Forest product usage reduces the use of alternative products (e.g. plastic or concrete), the use of which increases carbon emissions.
- Forest albedo or radiation reflectance is less than on open land, especially in early spring. This causes a climate warming effect of forests. Albedo particularly reduces the carbon sink effect of boreal forests.
- Global warming speeds up decomposition,which releases forest soil carbon to the atmosphere.
- Peatland drainage for forestry may increase carbondioxide and nitrogenoxide emissions (warming effect). Drainage, however, reduces the release of methane (a cooling effect).