Kyoto: Tradable greenhouse emission permits in the transport sector

Tradable permits in greenhouse gases are a key, last-minute provision incorporated in the Protocol agreed in Kyoto in December 1997, but the details of any future scheme remain to be negotiated. If an effective scheme is to be implemented, it needs to take account of issues such as the fact that international transport emissions are currently recorded, but not attributed to specific countries; possible distortions, because the Kyoto Protocol targets only radiatively direct greenhouse gases; the need for compatibility with 'green' national accounts, and business accounting conventions for treating environmental assets and liabilities; and the need for scientific clarification on the calculation of CO₂ equivalents for long-term carbon sinks. Given the transaction costs involved in tradable permit schemes, it is worth asking whether a carbon tax may be preferable in sectors such as transport.