Using timber tackles climate change. Policy makers and specifiers looking for ways of reducing global warming, have focused on the key role played by forests and solid timber products in the locking up of immense quantities of carbon dioxide, mainly because of the very cost-effective way in which they do this. Trees soak up carbon through photosynthesis and store it as solid wood. Almost 50% of the dry weight of a tree is carbon. Young forests absorb more carbon dioxide than they emit through respiration because a relatively large proportion of the carbon is used to create new wood. Mature and managed forests act as a long term carbon store.