When forests are cut they are no longer able to serve as a sink for atmospheric carbon. Sustainable forestry initiatives try to ensure that forests are maintained as forest sinks through replanting initiatives but even so-called sustainable forestry does not always lead to consistent uptake of atmospheric carbon because the rate of uptake of carbon by large trees can be greater than the rate of uptake by seedlings. New plantings may not be designed to consistently sequester the same weight of carbon per hectare as the forests that have been cut.
Now a paper in the scientific journal Nature Climate Change is drawing attention to the fact that the rate at which the carbon contained in cut trees returns to the atmosphere is significantly dependent on the uses made of the wood. If wood is pulped for paper, paper is a product with a generally short lifetime and much of the carbon will be returned to the atmosphere very quickly. If wood is made into furniture or buildings, it will have a long lifetime and the carbon contained within it will be sequestered for decades.
The research paper demonstrates that the median carbon stored in wood 30 years after it was cut is 36% for Europe, the United States and Canada and 2% for the rest of world. The authors claim that this aspect of the fate of cleared forest has not previously been given adequate consideration in climate models.
As part of their research the authors have developed a global set of dynamic carbon-storage factors that can be used to improve climate models and help develop carbon-mitigating bioenergy policies.
The paper in Nature Climate Change is available at http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate1535.html