New Algorithm Helps in Boreal Forest Biomass Assessment
29.03.2010 - Atmosphere & Space, Flora & Fauna, Arctic
A new processing algorithm developed thanks to images from the Advanced Synthetic Aperture Radar (ASAR) on ESA’s Envisat satellite will allow for the retrieval of boreal forest biomass well beyond levels previously reported.
Forests are a crucial link in the Earth’s carbon cycle and absorb carbon from the atmosphere before storing it in the biomass. Boreal forests, which cover some 16 million km² of the Earth’s surface, store a third more carbon per hectare than tropical forests. However, the regions are generally considered areas of increased warming and thus represent possible important tipping points for abrupt climate change.
Due to the lack of high-precision maps of biomass, it has remained the big unknown factor in the carbon cycle. The newly-developed algorithm might offer a first step in the right direction to solve the mystery.
The results of the algorithm, which have been fully validated by the BIOMASAR project, show that the retrieval of forest growing stock volume (GSV) – the amount of wood expressed in cubic metres per hectare – is possible from Envisat ASAR data in boreal forests well beyond the levels that have been reported previously.
By using this method we can reasonably expect to be able to generate global maps of GSV yearly over the entire boreal forest with a better resolution and more accuracy. These maps would be extremely important for improving forest management, from forest fire protection to any forest management activity.
While it is the first time that available data and simple tools provide a spatially consistent description of forests, the validated algorithm is expected to be applied over almost the entire Northern Boreal Forest Zone and used in creating maps of land-use change and biomass loss. In future applications, the algorithm might be used to create and update maps for temperate forest and savannah biomes.
