This paper sets up an input-output system of the relevant ecosystem flows that determine the carbon cycle in the global ecosystem. Introducing energy as the value added component in the ecosystem, the flows can be expressed in "energy values". Linking the ecosystem input-output model with the economy input-output model allows to calculate the ecosystem costs of excessive fossil energy use in terms of additional carbon sinks for emission absorption, that need solar energy input, i.e. "ecological value added". The model lined out in this paper enables to calculate costs and prices of the ecosystem due to anthropogenic fossil energy use. It might be useful (i) to derive sustainability indicators and (ii) as a framework for environment-economy links in E3 models.