非表示:
キーワード:
Biosphere; Carbon; Carbon accounting; Carbon trading; Emissions; Forest sink; Greenhouse; Kyoto Protocol; UNFCCC
要旨:
The Kyoto Protocol aims to reduce net emissions of greenhouse gases to the atmosphere by various measures including through management of the biosphere. However, the wording that has been adopted may be difficult and costly to implement, and may ultimately make it impossible to cost-effectively include biosphere management to reduce net greenhouse gas emissions. An alternative scheme is proposed here, especially for the second and subsequent commitment periods, to more effectively deal with the anthropogenic component of carbon stock changes in the biosphere. It would categorise the terrestrial biosphere into different land-use types, with each one having a characteristic average carbon density determined by land-use and environmental factors. Each transition from one land-use type to another, or a change in average carbon density within a specified type due to changed management would be defined as anthropogenic and credited or debited to the responsible nation. To calculate annual credits and/or debits, the change in average carbon stocks must be divided by a time constant which would either be a characteristic of each possible land-use conversion, or applicable to the sum of changes to a nation's biospheric carbon stocks. We believe that this scheme would be simpler and less expensive to implement than one based on the measurement of actual carbon changes from all specified areas of land. It would also avoid undue credits or debits, because they would only accrue as a result of identified anthropogenic components of biospheric carbon changes whereas carbon fluxes that are due to natural variation would not be credited or debited.
