Having a large-scale boreal forest biomass inventory would allow scientists to understand better the carbon cycle and to predict more accurately Earth's future climate. However, obtaining these maps has been wrought with difficulty until now.
A new processing algorithm has been developed using stacks of images from the Advanced Synthetic Aperture Radar (ASAR) on ESA's Envisat satellite that allows for the retrieval of boreal forest biomass well beyond the levels that have been previously reported. Forests play a crucial role in Earth's carbon cycle by absorbing carbon from the atmosphere and storing it in biomass. Undisturbed forests are carbon sinks as they absorb carbon, while forests that are logged or burnt down become carbon sources as they release carbon into the atmosphere.
Boreal forests and woodlands are estimated to cover approximately 14.5% of Earth's land surface, comprising an area of nearly 16 million sq km (about the size of the contiguous 48 states of the US). The boreal forest ecosystem, which spans Russia, northern Europe, Canada and Alaska, comprises interrelated habitats made up of forests, lakes, wetlands, rivers and tundra.
Boreal forests including forest soil store a third more carbon stocks per hectare as tropical forests, making them one of the most significant carbon sinks in the world. These regions are considered global hotspots, i.e. areas of increased warming, which represent possible important tipping points for abrupt climate change.
"Biomass, one of the most essential climate variables defining the functions of the Earth system, is the big unknown factor in the carbon cycle. Since no biomass maps exist with a high level of accuracy, we do not know how much is changing and cannot do calculations with any certainty. With this new algorithm, it is the first time that we have something in hand that may be a first step to a global biomass map," said Prof. Christiane Schmullius with the Fri
|Contact: Robert Meisner|
European Space Agency