Woodland carbon estimates are based on data supplied by the Forestry Commission's world leading Forest Research department. Carbon estimates are project specific, based on species mix and management plan, and local data such as soil type and altitude. In addition estimates will be adjusted based on local forestry knowledge.
Conservatism is a key Kyoto principle - you must be sure at all times that at least as much carbon is being captured by a project as was anticipated and sold to the carbon buyer. The Woodland Carbon Code provides several ways to ensure that this is the case, through the following processes:
Forestry Commission Ecological Site Classification (ESC) model
Before we start we need to know what trees to plant, and how they will behave where they are planted. The Forestry Commission ESC model gives us this information we need, based on latitude, longitude, altitude, soil type and meteorology of the site we are looking at.
Woodland Carbon Code buffering
The Woodland Carbon Code carbon model, developed by Forest Research, projects how much CO2 the trees will capture at a given location, based on the planting density and management regime. It then deducts a percentage of this projection automatically, as a contingency, based on the potential for the estimates to be inaccurate. This is the first phase of the buffering - reducing the carbon capture that can be sold to ensure that the conservatism rule is met. After this a risk deduction is made, in case something should happen at a project that causes some of it to fail.